SOUTHWEST RESEARCH INSTITUTE ®

6220 CULEBRA ROAD  POST OFFICE DRAWER 28510  SAN ANTONIO, TEXAS, USA 78228-0510  (210) 684-5111  www.swri.org

ENGINE, EMISSIONS, AND VEHICLE RESEARCH DIVISION HTTP://ENGINEANDVEHICLE .SWRI.ORG

FAX: (210) 522-3950 ISO 9001 Certified 

ISO 14001 Certified 

    SAN ANTONIO, TEXAS 

HOUSTON, TEXAS  WASHINGTON, DC  ANN ARBOR, MI 

 April 13, 2011 

Mr. Joseph Bachman 

USEPA Headquarters 

Ariel Rios Building 

1200 Pennsylvania Avenue, N.W. 

Mail Code: 6406J 

Washington, DC 10460 

SUBJECT: SwRI® Draft Final Report 03- 15847, EPA WA-1104 Titled, "Task Order No. 

1104 under BPA-GA-23F-0006M, Fuel Economy and Emission Testing Support 

Task” 

1.0 INTRODUCTION

 US EPA delivered three heavy-duty, on-road tractors to SwRI for the purposes of measuring 

greenhouse gas emissions of each truck over various drive cycles on a chassis dynamometer using various 

road load and test inertia configurations representative of common tractor-trailer combinations used in the 

US. Each truck configuration was hot-start tested over the transient cycle, shown in Figure 1, a ten 

minute, 55 mph steady-state cruise cycle, and a ten minute 65 mph steady-state cycle. The two, tandemaxle Class 8 trucks were also tested for ten minutes at idle. Ten minutes of settling time preceded 

sampling of the steady-state tests and cruise control was used during the 55 mph and 65 mph tests. 

 The chassis dynamometer used during this project is equipped with one 48-inch diameter roll per 

drive axle. Vehicle inertia and road load is simulated by a 300-hp electric motor coupled to the 

dynamometer roll. Each motor is capable of simulating 60,000 lb of inertia. The following emissions 

were measured during each test: 

 Total hydrocarbons, HC 

 Methane, CH4

 Oxides of nitrogen, NOX

 Nitrogen oxide, NO 

 Nitrous Oxide, N2O 

 Carbon Monoxide, CO 

 Carbon dioxide, CO2

 Particulate Matter, PM 

Ultra-low sulfur diesel fuel meeting EPA certification specifications was used for all of the tests. 
Mr. Joseph Bachman 

USEPA Headquarters 

April 13, 2011 

Page 2 of 20 

Draft Report 03-15847 WA 1104 

FIGURE 1. EPA TRANSIENT CYCLE 

2.0 TEST RESULTS 

The original plan was to test each configuration over each drive cycle five to seven times 

in order to get at least three fuel economy values with a coefficient of variation of approximately 

one percent, which is the typical coefficient variation observed on the dynamometer with these 

types of trucks. Therefore, depending on the variability observed during testing, between three 

and seven valid tests were conducted for each configuration for a given drive cycle. It was 

observed during testing that the steady-state test results varied as much as the transient tests, 

which suggests that the driver during transient tests is not a larger contributor to test variability. 

2.1 Truck 1660-HD-01

The first truck tested, 1660-HD-01 shown in Figure 2, was a 2009 MY International ProStar 

tandem-axle sleeper cab equipped with a Cummins ISX 450ST engine and 10-speed 

transmission, as described in Table 1. The truck was tested over EPA Transient, 55 mph steadystate, and 65 mph steady-state cycles multiple times for each configuration shown in Table 2. 

The results of the testing are shown Tables 3 through 11. The truck was idle tested three times 

and the results are in Table 12. 

 

 

0

5

10

15

20

25

30

35

40

45

50

0 100 200 300 400 500 600 700

Vehicle Speed, mph

Time, seconds
Mr. Joseph Bachman 

USEPA Headquarters 

April 13, 2011 

Page 3 of 20 

Draft Report 03-15847 WA 1104 

FIGURE 2. TRUCK 1660-HD-01, 2009 MY INTERNATIONAL PROSTAR 

TANDEM-AXLE SLEEPER CAB 

TABLE 1. DESCRIPTION OF TRUCK 1660-HD-01 

TRACTOR 1660-HD-01

Vehicle VIN 2HSCUAPR6AC168660

Transmission Type Manual 10 Spd.

Transmission Model Eaton Fuller FRO 16210C

Engine Family on Engine Label 9CEXH0912XAK

Engine Manufacturer Cummins

Engine Model ISX 450 ST

Serial Number 5066623

Engine Build Date Feb-09

Horsepower Rating on Label 450 hp

Rated Speed 2100 RPM

Torque Rating 1550 lb-ft

Torque Speed 1200 RPM

Emission Controls EPA-07
Mr. Joseph Bachman 

USEPA Headquarters 

April 13, 2011 

Page 4 of 20 

Draft Report 03-15847 WA 1104 

TABLE 2. TRUCK 1660-HD-01 TEST CONFIGURATIONS 

Configuration 

Number Configuration 

Test 

Weight, 

lb 

Coastdown 

Configuration 

Dyno Set 

Inertia, lb 

F0, 

lbf 

F2, 

lbf/mph2

1.1 Model: International Prostar 

Cab: Sleeper 

Roof: High 

Trailer: Box 

Aerodynamic Fairings: Yes 

70,500 18 tires/5 axles 71,750 594.9 0.140 

1.2 Model: International Prostar 

Cab: Sleeper 

Roof: High 

Trailer: Flat bed 

Aerodynamic Fairings: Yes

70,500 18 tires/5 axles 71,750 620.2 0.139 

1.3 Model: International Prostar 

Cab: Sleeper 

Roof: High 

Trailer: Tandem box 

Aerodynamic Fairings: Yes 

70,500 22 tires/6 axles 72,250 594.1 0.141 

TABLE 3. TEST RESULTS FOR 1660-HD-01 USING CONFIGURATION 

1.1 OVER EPA TRANSIENT CYCLE 

Test Date Test Name 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

7/23/2010 8660-T-H5 0.0000 0.0137 6.13 4.40 54.4 0.124 3180 1.08 3.18 2.96

7/23/2010 8660-T-H6 0.0000 0.00987 6.55 4.64 51.5 0.246 3169 0.476 3.19 2.95

7/23/2010 8660-T-H7 0.0000 0.00887 7.00 4.96 52.3 0.153 3152 1.01 3.21 2.97

7/23/2010 8660-T-H8 0.0000 0.00884 7.28 5.67 100 0.566 3127 1.17 3.23 2.95

7/23/2010 8660-T-H9 0.0383 0.0104 6.84 5.10 115 0.172 3204 2.60 3.15 2.99

Average 0.00765 0.0103 6.76 4.96 74.6 0.252 3166 1.27 3.19 2.96

c.o.v. 224% 19% 6.5% 9.7% 41% 72% 0.92% 62% 0.91% 0.56%

 
Mr. Joseph Bachman 

USEPA Headquarters 

April 13, 2011 

Page 5 of 20 

Draft Report 03-15847 WA 1104 

TABLE 4. TEST RESULTS FOR 1660-HD-01 USING CONFIGURATION 

1.1 OVER 55 MPH STEADY-STATE CYCLE 

Test Date Test Name 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance,

miles 

7/26/2010 8660-55C-H1 0.0000 0.0000 1.87 0.818 10.3 0.00000 1395 0.4133 7.25 9.22

7/26/2010 0.0000 0.0000 1.88 0.791 9.80 0.00506 1366 0.4512 7.40 9.31

7/26/2010 8660-55C-H3 0.0000 0.0000 1.73 0.708 11.0 0.00475 1350 0.4328 7.49 9.22

Average 0.0000 0.0000 1.83 0.772 10.4 0.00327 1370 0.4325 7.38 9.25

c.o.v. 0.00% 157% 4.5% 7.5% 5.9% 87% 1.7% 4.4% 1.6% 0.56%

TABLE 5. TEST RESULTS FOR 1660-HD-01 USING CONFIGURATION 

1.1 OVER 65 MPH STEADY-STATE CYCLE 

Test Date Test Name 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

7/23/2010 8660-65C-H1 0.0000 0.0000 3.58 1.46 10.8 0.000 1435 0.488 7.04 10.8 

7/23/2010 8660-65C-H2 0.0000 0.0000 3.35 1.41 10.8 0.000 1446 0.620 6.99 10.8 

7/23/2010 8660-65C-H3 0.0000 0.0000 3.28 1.43 10.8 0.000 1465 0.535 6.90 10.9 

Average 0.0000 0.0000 3.40 1.43 10.79 0.000 1449 0.548 6.98 10.8 

c.o.v. 0.00% 0.00% 4.6% 1.8% 0.42% 0.00% 1.0% 12.3% 1.0% 0.58% 

TABLE 6. TEST RESULTS FOR 1660-HD-01 USING CONFIGURATION 

1.2 OVER EPA TRANSIENT CYCLE 

Test Date Test Name 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

7/29/2010 8660-TFB-H2 0.0898 0.00664 7.35 4.75 54.8 0.0329 3124 0.000 3.24 2.98

7/29/2010 8660-TFB-H3 0.0856 0.00797 7.31 4.76 59.4 0.0642 3148 0.354 3.21 2.96

7/29/2010 8660-TFB-H4 0.0819 0.00791 7.37 4.93 49.8 0.0986 3140 0.888 3.22 2.99

7/29/2010 8660-TFB-H5 0.0751 0.00493 7.44 4.89 40.9 0.219 3127 0.548 3.23 2.94

7/29/2010 8660-TFB-H6 0.0629 0.00452 7.38 4.90 49.5 0.110 3124 0.162 3.24 2.98

Average 0.079 0.00640 7.37 4.85 50.9 0.105 3133 0.390 3.23 2.97

c.o.v. 13% 25% 0.63% 1.8% 14% 67% 0.34% 89% 0.34% 0.67%

 
Mr. Joseph Bachman 

USEPA Headquarters 

April 13, 2011 

Page 6 of 20 

Draft Report 03-15847 WA 1104 

TABLE 7. TEST RESULTS FOR 1660-HD-01 USING CONFIGURATION 

1.2 OVER 55 MPH STEADY-STATE CYCLE 

Test Date Test Name 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

7/28/2010 8660-55FB-H1 0.0212 0.000448 1.97 0.90 12.7 0.000 1377 0.453 7.34 9.23

7/29/2010 8660-55FB-H4 0.0184 0.000000 2.06 0.81 9.39 0.000 1353 0.000 7.47 9.24

7/29/2010 8660-55FB-H5 0.0127 0.000000 1.85 0.71 8.44 0.000 1362 0.238 7.42 9.23

 Average 0.0175 0.000149 1.96 0.81 10.2 0.000 1364 0.230 7.41 9.23

 c.o.v. 25% 173% 5.6% 11% 22% #DIV/0! 0.89% 98% 0.89% 0.06%

TABLE 8. TEST RESULTS FOR 1660-HD-01 USING CONFIGURATION 

1.2 OVER 65 MPH STEADY-STATE CYCLE 

Test Date Test Name 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

7/27/2010 8660-65FB-H1 0.0350 0.0000 3.44 1.74 8.78 0.000 1541 0.269 6.56 10.9

7/27/2010 8660-65FB-H2 0.0219 0.0000 3.28 1.69 7.80 0.000 1523 0.280 6.64 11.0

7/28/2010 8660-65FB-H3 0.0249 0.0000 3.65 1.88 13.3 0.000 1542 0.329 6.56 10.9

7/28/2010 8660-65FB-H4 0.0199 0.0000 3.55 1.82 13.0 0.000 1512 0.0867 6.69 10.9

7/28/2010 8660-65FB-H5 0.0171 0.0000 3.42 1.78 11.4 0.000 1491 0.128 6.78 10.9

7/28/2010 8660-65FB-H6 0.0173 0.0000 3.50 1.83 12.7 0.000 1480 0.448 6.83 10.9

 Average 0.0227 0.0000 3.47 1.79 11.15 0.000 1515 0.257 6.68 10.9

 c.o.v. 30% 0.00% 3.6% 3.9% 21% 0.00% 1.7% 52% 1.7% 0.44%

TABLE 9. TEST RESULTS FOR 1660-HD-01 USING CONFIGURATION 

1.3 OVER EPA TRANSIENT CYCLE 

Test Date Test Name 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

g/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

8/9/2010 8660-500-H1 0.959 0.0121 6.87 87.5 0.000 3056 0.00 3.30 2.99

8/9/2010 8660-500-H2 0.119 0.0114 7.26 51.0 0.532 3131 1.05 3.23 2.96

8/9/2010 8660-500-H4 0.0960 0.00567 6.72 50.2 0.109 3135 2.07 3.22 2.99

8/9/2010 8660-500-H5 0.0745 0.00598 6.50 3.25 47.8 0.105 3122 0.00 3.24 2.98

8/9/2010 8660-500-H6 0.0846 0.00755 7.10 3.51 48.8 0.089 3154 1.08 3.20 2.95

 Average 0.266 0.00852 6.89 3.38 57.1 0.167 3120 0.843 3.24 2.97

 c.o.v. 145% 35% 4.4% 5.3% 30% 125% 1.2% 103% 1.2% 0.61%
Mr. Joseph Bachman 

USEPA Headquarters 

April 13, 2011 

Page 7 of 20 

Draft Report 03-15847 WA 1104 

TABLE 10. TEST RESULTS FOR 1660-HD-01 USING CONFIGURATION 

1.3 OVER 55 MPH STEADY-STATE CYCLE 

Test Date Test Name 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

8/2/2010 8660-55T-H1 0.0253 0.000308 2.10 1.03 13.3 0.00439 1382 0.000 7.31 9.23

8/2/2010 8660-55T-H2 0.0197 0.000000 1.96 0.920 10.8 0.00110 1350 0.000 7.49 9.21

8/2/2010 8660-55T-H3 0.0150 0.000000 2.13 1.00 11.3 0.00000 1364 0.204 7.41 9.36

8/2/2010 8660-55T-H4 0.0137 0.000354 1.89 0.877 7.65 0.00000 1344 0.495 7.52 9.30

8/2/2010 8660-55T-H5 0.0165 0.000000 1.94 1.68 8.27 0.00540 1327 0.262 7.62 9.32

8/2/2010 8660-55T-H6 0.0141 0.000096 1.76 0.579 8.77 0.00994 1327 0.348 7.62 9.17

 Average 0.0158 0.000090 1.94 1.01 9.37 0.00329 1343 0.262 7.53 9.27

 c.o.v. 15% 170% 6.9% 40% 17% 132% 1.2% 70% 1.2% 0.85%

TABLE 11. TEST RESULTS FOR 1660-HD-01 USING CONFIGURATION 

1.3 OVER 65 MPH STEADY-STATE CYCLE 

Test Date Test Name 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

8/3/2010 8660-65T-H1 0.0188 0.0000 3.53 1.31 12.0 0.000 1542 0.236 6.56 10.8 

8/3/2010 8660-65T-H2 0.0129 0.0000 3.42 0.142 11.8 0.000 1510 0.249 6.70 10.9 

8/3/2010 8660-65T-H3 0.0133 0.0000 3.41 1.32 10.7 0.000 1480 0.402 6.83 10.9 

8/3/2010 8660-65T-H4 0.0131 0.0000 3.00 0.00 11.3 0.000 1468 0.245 6.89 10.8 

8/3/2010 8660-65T-H5 0.0146 0.0000 3.20 0.00 11.7 0.000 1494 0.141 6.77 10.8 

8/3/2010 8660-65T-H6 0.0106 0.0000 3.13 0.00 11.4 0.000 1478 0.376 6.84 10.8 

 Average 0.0139 0.0000 3.28 0.464 11.5 0.000 1495 0.275 6.76 10.9 

 c.o.v. 20% 0.0000 6.2% 143% 3.9% 0.000 1.8% 35% 1.8% 0.34% 

TABLE 12. TEST RESULTS FOR 1660-HD-01 OVER IDLE STEADY-STATE CYCLE 

Test Date Test Name 

HC, 

g/hr 

CH4, 

g/hr 

NOx, 

g/hr 

NO, 

g/hr 

N2O, 

mg/hr 

CO, 

g/hr 

CO2, 

g/mile 

PM, 

mg/hr 

Fuel 

Econ., 

gal/hr 

Time, 

hr 

7/26/2010 8660-I-H1A 0.00 0.0000 12.5 11.5 13.1 27.4 6294 28.5 0.627 0.170

7/26/2010 8660-I-H2A 1.83 0.0790 11.8 11.3 34.2 31.6 6225 30.8 0.621 0.170

7/26/2010 8660-I-H3A 6.33 0.0603 12.6 11.5 14.7 31.5 6277 7.64 0.626 0.170

 Average 2.72 0.0465 12.3 11.4 20.7 30.1 6265 22.3 0.625 0.170

 c.o.v. 120% 89% 3.2% 1.1% 57% 8.0% 0.57% 57% 0.53% 0.00%

 
Mr. Joseph Bachman 

USEPA Headquarters 

April 13, 2011 

Page 8 of 20 

Draft Report 03-15847 WA 1104 

2.2 Truck 1660-HD-02A 

Truck 1660-HD-02A shown in Figure 3, was a 2009 MY International ProStar tandem-axle 

day cab equipped with a Cummins ISX 450ST engine and 10-speed transmission, as described in 

Table 13. The truck was tested over EPA Transient, 55 mph steady-state, and 65 mph steadystate cycles multiple times for each configuration shown in Table 14. The results of the testing 

are shown Tables 15 through 26. The truck was idle tested three times and the results are in 

Table 27. 

FIGURE 3. TRUCK 1660-HD-02A, 2009 MY INTERNATIONAL 

PROSTAR TANDEM-AXLE DAY CAB 

 
Mr. Joseph Bachman 

USEPA Headquarters 

April 13, 2011 

Page 9 of 20 

Draft Report 03-15847 WA 1104 

TABLE 13. DESCRIPTION OF TRUCK 1660-HD-02A 

TRACTOR 1660-HD-02A

Vehicle VIN 2HSCUAPR5AC169685 

Transmission Type Manual 10 Spd. 

Transmission Model Eaton Fuller FRO 16210C 

Engine Family on Engine Label 9CEXH0912XAK 

Engine Manufacturer Cummins 

Engine Model ISX 450 ST 

Serial Number 5061564 

Engine Build Date Jan-09 

Horsepower Rating on Label 450 hp 

Rated Speed 2100 RPM 

Torque Rating 1550 lb-ft 

Torque Speed 1200 RPM 

Emission Controls EPA-07 

 
Mr. Joseph Bachman 

USEPA Headquarters 

April 13, 2011 

Page 10 of 20 

Draft Report 03-15847 WA 1104 

TABLE 14. TRUCK 1660-HD-02A TEST CONFIGURATIONS 

Configuration 

Number Coastdown Configuration 

Test 

Weight, 

lb 

Coastdown 

Configuration

Dyno Set 

Inertia, lb 

F0, 

lbf 

F2, 

lbf/mph2

2.1 

Model: International 

Prostar 

Cab: Day 

Roof: Low 

Trailer: Flatbed 

Aerodynamic Fairings: 

No

65,500 18 tires/5 axles 66,750 569.5 0.115 

2.2 

Model: International 

Prostar 

Cab: Day 

Roof: Low 

Trailer: Box 

Aerodynamic Fairings: 

No 

65,500 18 tires/5 axles 66,750 491.4 0.196 

2.3 

Model: International 

Prostar 

Cab: Day 

Roof: High 

Trailer: Flatbed 

Aerodynamic Fairings: 

No

69,000 18 tires/5 axles 70,250 564.8 0.165 

2.4 

Model: International 

Prostar 

Cab: Day 

Roof: High 

Trailer: Box 

Aerodynamic Fairings: 

No 

69,000 18 tires/5 axles 70,250 620.5 0.154 

TABLE 15. TEST RESULTS FOR 1660-HD-02A USING CONFIGURATION 

2.1 OVER EPA TRANSIENT CYCLE 

Test 

Date Test Name 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

9/14/2010 9685-TRAN-H1 0.588 0.0248 6.49 3.37 115 1.37 2982 0.437 3.39 3.01

9/14/2010 9685-TRAN-H2 0.0662 0.0196 6.21 2.64 59.2 0.173 2950 0.278 3.43 3.01

9/14/2010 9685-TRAN-H3 0.0818 0.0199 6.24 2.79 52.2 0.113 2981 0.975 3.39 2.99

9/14/2010 9685-TRAN-H4 0.0707 0.0135 6.18 2.93 47.8 0.092 2984 5.17 3.39 3.02

9/14/2010 9685-TRAN-H5 0.291 0.0192 6.56 3.42 82.7 0.584 2971 1.62 3.40 2.98

9/14/2010 9685-TRAN-H6 0.0581 0.0144 6.46 3.27 54.0 0.108 2973 0.856 3.40 3.04

 Average 0.193 0.0186 6.36 3.07 68.6 0.406 2974 1.56 3.40 3.01

 c.o.v. 111% 22% 2.6% 11% 38% 125% 0.42% 118% 0.44% 0.71%
Mr. Joseph Bachman 

USEPA Headquarters 

April 13, 2011 

Page 11 of 20 

Draft Report 03-15847 WA 1104 

TABLE 16. TEST RESULTS FOR 1660-HD-02A USING CONFIGURATION 

2.1 OVER 55 MPH STEADY-STATE CYCLE 

Test Date Test Name 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

9/9/2010 9685-55-H1 0.0350 0.00281 1.15 0.348 9.90 0.0177 1197 0.967 8.45 9.26

9/9/2010 9685-55-H2 0.0325 0.00278 1.22 0.392 9.34 0.0193 1196 0.517 8.45 9.19

9/9/2010 9685-55-H3 0.0344 0.00289 1.25 0.396 7.88 0.0160 1181 0.000 8.56 9.26

9/9/2010 9685-55-H4 0.0296 0.00276 1.27 0.436 9.48 0.0161 1161 0.000 8.71 9.19

9/9/2010 9685-55-H5 0.0259 0.00261 1.28 0.468 9.72 0.0189 1164 0.287 8.69 9.16

9/9/2010 9685-55-H6 0.0279 0.00345 1.29 0.471 9.50 0.0227 1152 0.201 8.78 9.13

 Average 0.0309 0.00289 1.24 0.418 9.30 0.0185 1175 0.329 8.61 9.20

 c.o.v. 12% 10% 4.2% 12% 7.8% 13% 1.6% 112% 1.6% 0.57%

TABLE 17. TEST RESULTS FOR 1660-HD-02A USING CONFIGURATION 

2.1 OVER 65 MPH STEADY-STATE CYCLE 

Test Date Test Name 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

9/10/2010 9685-65-H1 0.0479 0.000 1.97 0.723 26.4 0.0105 1337 0.118 7.56 10.8

9/10/2010 9685-65-H2 0.0392 0.000 1.91 0.716 12.7 0.00679 1317 0.305 7.67 10.8

9/10/2010 9685-65-H3 0.0393 0.000 1.91 0.679 11.8 0.0132 1319 0.0716 7.66 10.9

9/10/2010 9685-65-H4 0.0402 0.000 1.97 0.631 10.2 0.0151 1332 0.434 7.59 10.9

9/10/2010 9685-65-H5 0.0444 0.000 1.89 0.720 11.4 0.0110 1328 0.291 7.61 10.9

9/10/2010 9685-65-H6 0.0430 0.000 1.89 0.715 11.4 0.0101 1326 0.000 7.62 10.9

 Average 0.0423 0.000 1.92 0.697 14.0 0.0111 1327 0.203 7.62 10.9

 c.o.v. 8.2% 0.00% 2.0% 5.2% 44% 26% 0.55% 81% 0.55% 0.43%

TABLE 18. TEST RESULTS FOR 1660-HD-02A USING CONFIGURATION 

2.2 OVER EPA TRANSIENT CYCLE 

Test Date Test Name 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

11/19/2010 9685-T-H1 0.0403 0.00765 7.11 3.29 57.5 0.130 2972 1.25 3.40 2.99

11/19/2010 9685-T-H2 0.236 0.0151 6.71 3.65 85.8 0.370 2884 0.571 3.50 2.96

11/19/2010 9685-T-H3 0.111 0.00982 6.69 3.43 73.7 0.166 2952 1.12 3.42 2.92

11/19/2010 9685-T-H4 0.0995 0.0128 6.55 3.25 66.0 0.123 3002 0.525 3.37 2.95

11/19/2010 9685-T-H5 0.0531 0.00861 6.61 3.18 58.5 0.089 2908 0.888 3.48 2.94

11/19/2010 9685-T-H6 0.102 0.0106 7.14 3.68 78.2 0.105 2932 0.583 3.45 2.95

 Average 0.107 0.0107 6.80 3.41 69.9 0.164 2942 0.822 3.44 2.95

 c.o.v. 65% 26% 3.8% 6.2% 16% 64% 1.5% 38% 1.5% 0.78%

 
Mr. Joseph Bachman 

USEPA Headquarters 

April 13, 2011 

Page 12 of 20 

Draft Report 03-15847 WA 1104 

TABLE 19. TEST RESULTS FOR 1660-HD-02A USING CONFIGURATION 

2.2 OVER 55 MPH STEADY-STATE CYCLE 

Test Date Test Name 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

11/22/2010 9685-55-H7 0.0282 0.000788 1.76 0.620 8.92 0.0000 1424 0.179 7.10 9.13

11/22/2010 9685-55-H8 0.0300 0.000594 1.68 0.628 8.64 0.00712 1388 6.39 7.28 9.21

11/22/2010 9685-55-H9 0.0282 0.000839 1.55 0.643 11.8 0.0138 1394 1.06 7.25 9.17

11/22/2010 9685-55-H10 0.0250 0.00163 1.54 0.647 8.55 0.0130 1392 0.00 7.26 9.19

11/22/2010 9685-55-H11 0.0257 0.00124 1.54 0.624 8.91 0.0121 1395 0.330 7.24 9.18

11/22/2010 9685-55-H12 0.0244 0.00157 1.54 0.636 8.91 0.0104 1386 0.306 7.30 9.16

 Average 0.0269 0.00111 1.60 0.633 9.29 0.00940 1396 1.38 7.24 9.17

 c.o.v. 8.1% 39% 5.9% 1.7% 13% 55% 0.99% 180% 0.98% 0.30%

TABLE 20. TEST RESULTS FOR 1660-HD-02A USING CONFIGURATION 

2.2 OVER 65 MPH STEADY-STATE CYCLE 

Test Date Test Name 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

11/18/2010 9685-65-H1 0.0707 0.0000 4.63 1.34 12.9 0.00698 1627 0.387 6.21 10.8

11/18/2010 9685-65-H2 0.0798 0.0000 4.68 1.54 11.9 0.00074 1630 0.147 6.20 10.9

11/18/2010 9685-65-H3 0.107 0.0000 4.49 1.63 10.8 0.00127 1624 0.427 6.22 10.9

11/18/2010 9685-65-H4 0.0854 0.0000 4.37 1.44 17.2 0.00255 1615 0.263 6.26 10.8

11/18/2010 9685-65-H5 0.0902 0.0000 4.31 1.37 11.0 0.00000 1643 0.000 6.15 10.8

11/18/2010 9685-65-H6 0.0835 0.0000 4.19 1.44 10.9 0.00599 1625 0.122 6.22 10.8

 Average 0.0860 0.0000 4.45 1.46 12.5 0.00292 1627 0.224 6.21 10.8

 c.o.v. 14% #DIV/0! 4.2% 7.5% 20% 99% 0.56% 73% 0.56% 0.31%

TABLE 21. TEST RESULTS FOR 1660-HD-02A USING CONFIGURATION 

2.3 OVER EPA TRANSIENT CYCLE 

Test Date Test Name 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

11/24/2010 9685-70K-T-H1 0.120 0.0216 6.17 2.47 63.6 0.324 3066 0.323 3.30 3.00

11/24/2010 9685-70K-T-H2 0.152 0.0108 6.28 3.21 71.5 0.311 3033 0.832 3.33 3.00

11/24/2010 9685-70K-T-H3 0.169 0.0112 6.11 3.22 75.9 0.157 3076 1.31 3.29 2.96

11/24/2010 9685-70K-T-H4 0.144 0.0128 6.44 2.94 77.5 0.245 3104 0.356 3.26 2.97

11/24/2010 9685-70K-T-H5 0.147 0.0128 6.13 3.06 76.1 0.210 3069 0.000 3.29 2.97

11/24/2010 9685-70K-T-H6 0.130 0.0111 6.00 3.19 74.2 0.142 3099 0.767 3.26 2.98

 Average 0.144 0.0134 6.19 3.02 73.2 0.232 3074 0.598 3.29 2.98

 c.o.v. 12% 31% 2.5% 9.5% 7.0% 33% 0.84% 78% 0.84% 0.56%
Mr. Joseph Bachman 

USEPA Headquarters 

April 13, 2011 

Page 13 of 20 

Draft Report 03-15847 WA 1104 

TABLE 22. TEST RESULTS FOR 1660-HD-02A USING CONFIGURATION 

2.3 OVER 55 MPH STEADY-STATE CYCLE 

Test Date Test Name 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

11/29/2010 9685-70K-55-H1 0.0288 0.0000 2.63 0.983 12.3 0.00384 1367 0.264 7.40 9.20 

11/29/2010 9685-70K-55-H2 0.0587 0.0000 2.50 0.744 8.35 0.0176 1334 0.179 7.58 9.20 

11/29/2010 9685-70K-55-H3 0.0230 0.0000 1.95 0.636 8.48 0.0141 1355 0.456 7.46 9.23 

11/29/2010 9685-70K-55-H4 0.0182 0.0000 1.87 0.622 8.52 0.0118 1363 0.110 7.42 9.22 

11/29/2010 9685-70K-55-H5 0.0210 0.0000 1.80 0.634 8.55 0.0110 1357 0.431 7.45 9.21 

 Average 0.0299 0.0000 2.15 0.724 9.24 0.0117 1355 0.288 7.46 9.21 

 c.o.v. 55% 0.00% 18% 21% 19% 43% 0.92% 53% 0.93% 0.14% 

TABLE 23. TEST RESULTS FOR 1660-HD-02A USING CONFIGURATION 

2.3 OVER 65 MPH STEADY-STATE CYCLE 

Test Date Test Name 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

11/23/2010 9685-70K-65-H1 0.117 0.0000 3.25 1.27 11.4 0.00218 1592 0.577 6.35 10.9

11/23/2010 9685-70K-65-H2 0.0848 0.0000 3.21 1.35 11.6 0.00217 1587 0.391 6.37 10.9

11/23/2010 9685-70K-65-H3 0.339 0.0000 3.19 1.11 14.1 0.00000 1611 0.431 6.27 11.0

11/23/2010 9685-70K-65-H4 0.0964 0.0000 3.04 1.11 10.4 0.00000 1587 0.401 6.37 10.8

11/23/2010 9685-70K-65-H5 0.0970 0.0000 3.10 1.14 10.9 0.00000 1596 0.385 6.33 10.9

11/23/2010 9685-70K-65-H6 0.0975 0.0000 3.14 1.22 11.0 0.00126 1590 0.280 6.36 10.9

 Average 0.139 0.0000 3.15 1.20 11.6 0.000934 1594 0.411 6.34 10.9

 c.o.v. 71% #DIV/0! 2.4% 8.1% 11% 115% 0.57% 23% 0.59% 0.40%

TABLE 24. TEST RESULTS FOR 1660-HD-02A USING CONFIGURATION 

2.4 OVER EPA TRANSIENT CYCLE 

Test Date Test Name 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

1/3/2011 9685-TRAN-H1A 0.651 0.0183 7.17 3.88 114 1.76 3092 2.67 3.26 2.94

1/3/2011 9685-TRAN-H2A 0.209 0.00873 6.99 3.73 97.4 0.298 3170 0.642 3.19 2.92

1/3/2011 9685-TRAN-H3A 0.460 0.0119 7.19 3.95 150 0.579 3193 0.918 3.16 2.91

1/3/2011 9685-TRAN-H4A 0.114 0.00976 6.91 3.53 119 0.255 3200 0.747 3.16 2.92

1/3/2011 9685-TRAN-H5A 0.155 0.0116 6.97 3.89 127 0.361 3190 1.77 3.17 2.91

 Average 0.318 0.0120 7.05 3.80 122 0.650 3169 1.35 3.19 2.92

 c.o.v. 72% 31% 1.8% 4.5% 16% 97% 1.4% 64% 1.4% 0.42%
Mr. Joseph Bachman 

USEPA Headquarters 

April 13, 2011 

Page 14 of 20 

Draft Report 03-15847 WA 1104 

TABLE 25. TEST RESULTS FOR 1660-HD-02A USING CONFIGURATION 

2.4 OVER 55 MPH STEADY-STATE CYCLE 

Test Date Test Name 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

12/29/2010 9685-55-H1A 0.0746 0.0000 2.69 0.981 10.5 0.0765 1387 0.5765 7.29 9.16

12/29/2010 9685-55-H3A 0.0373 0.0000 2.41 0.886 9.83 0.0828 1361 0.5153 7.43 9.17

12/29/2010 9685-55-H4A 0.0453 0.0000 2.67 0.948 10.0 0.0841 1371 0.0000 7.37 9.23

12/29/2010 9685-55-H5A 0.0427 0.0000 2.44 0.790 9.79 0.0562 1351 0.1442 7.48 9.18

 Average 0.0500 0.0000 2.55 0.901 10.0 0.0749 1368 0.3090 7.39 9.19

 c.o.v. 33% 0.00% 5.9% 9.3% 3.2% 17% 1.1% 91% 1.1% 0.34%

TABLE 26. TEST RESULTS FOR 1660-HD-02A USING CONFIGURATION 

2.4 OVER 65 MPH STEADY-STATE CYCLE 

Test Date Test Name 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

1/4/2011 9685-65-H1A 0.0907 0.0000 3.99 0.431 11.0 0.0853 1537 0.2423 6.58 10.9

1/4/2011 9685-65-H2A 0.0606 0.0000 3.67 1.09 10.7 0.0566 1537 0.0000 6.58 10.8

1/4/2011 9685-65-H3A 0.0668 0.0000 3.64 0.442 10.5 0.0470 1538 0.0000 6.57 10.9

1/4/2011 9685-65-H4A 0.0688 0.0000 3.53 1.10 10.9 0.0539 1529 0.2819 6.61 10.8

1/4/2011 9685-65-H5A 0.0827 0.0000 3.57 0.894 10.9 0.0480 1547 0.4957 6.53 10.9

 Average 0.0739 0.0000 3.68 0.791 10.8 0.0582 1537 0.2040 6.57 10.8

 c.o.v. 17% 0.00% 4.9% 42% 1.9% 27% 0.43% 100% 0.43% 0.36%

TABLE 27. TEST RESULTS FOR 1660-HD-02A OVER IDLE STEADY-STATE CYCLE 

Test Date Test Name 

HC, 

g/hr 

CH4, 

g/hr 

NOx, 

g/hr 

NO, 

g/hr 

N2O, 

mg/hr 

CO, 

g/hr 

CO2, 

g/mile 

PM, 

mg/hr 

Fuel 

Econ., 

gal/hr 

Time, 

hr 

9/14/2010 9685-I-H1 1.48 0.00508 18.4 15.0 78.3 14.98 5811 689 0.578 0.170

9/14/2010 9685-I-H2 2.48 0.0000 18.3 15.3 74.6 15.28 6144 729 0.612 0.170

9/15/2010 9685-I-H3 5.22 0.0201 17.9 14.4 106 14.38 6200 737 0.618 0.170

9/15/2010 9685-I-H4 3.20 0.0313 15.8 13.9 71.7 13.90 6226 740 0.621 0.170

9/15/2010 9685-I-H5 3.59 0.00393 16.1 13.8 76.4 13.83 6185 735 0.617 0.170

 Average 3.19 0.0121 17.3 14.5 81.5 14.48 6113 726 0.609 0.170

 c.o.v. 43% 109% 7.3% 4% 17% 4% 2.8% 2.9% 2.9% 0.00%
Mr. Joseph Bachman 

USEPA Headquarters 

April 13, 2011 

Page 15 of 20 

Draft Report 03-15847 WA 1104 

2.3 Truck 1660-HD-08 

Truck 1660-HD-08 shown in Figure 4, was a 2009 MY International ProStar single-axle day 

cab equipped with a Cummins ISX 425 engine and 10-speed transmission, as described in Table 

28. The truck was tested over EPA Transient, 55 mph steady-state, and 65 mph steady-state 

cycles multiple times for the configuration shown in Table 29. The results of the testing are 

shown Tables 30 through 32. 

FIGURE 4. TRUCK 1666-HD-08, 2009 INTERNATIONAL PROSTAR 

SINGLE-AXLE DAY CAB

 
Mr. Joseph Bachman 

USEPA Headquarters 

April 13, 2011 

Page 16 of 20 

Draft Report 03-15847 WA 1104 

TABLE 28. DESCRIPTION OF TRUCK 1660-HD-08 

TRACTOR 1660-HD-08

Vehicle VIN 2HSCSAPNXAC215045

Transmission Type Manual 10 Spd

Transmission Model Eaton Fuller FRO-16210B

Engine Family on Engine Label 9CEXH0912XAK

Engine Manufacturer Cummins

Engine Model ISX 425

Serial Number 5075285

Engine Build Date May-09

Horsepower Rating on Label 425

Rated Speed 1800

Torque Rating 1650

Torque Speed 1200

Emission Controls EPA-07

TABLE 29. TRUCK 1660-HD-08 TEST CONFIGURATION 

Configuration 

Number 

Coastdown 

Configuration 

Test 

Weight, lb 

Coastdown 

Configuration

Dyno Set 

Inertia, lb 

F0, 

lbf 

F2, 

lbf/mph2

3.1 

Model: International 

Prostar 

Cab: Day 

Roof: Low 

Trailer: Flatbed 

Aerodynamic 

Fairings: Yes

46,500 14 tires/4 axles 47,750 358.4 0.130 

TABLE 30. TEST RESULTS FOR 1660-HD-08 USING CONFIGURATION 

3.1 OVER EPA TRANSIENT CYCLE 

Test Date Test Name 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

12/20/2010 5045-TRAN-H1 0.997 0.0498 5.98 3.48 141 3.03 2471 14.4 4.08 2.98

12/20/2010 5045-TRAN-H2 0.424 0.0240 5.98 3.47 80.9 0.980 2511 10.9 4.02 2.93

12/20/2010 5045-TRAN-H3 0.479 0.0264 6.22 3.53 85.6 1.28 2467 9.64 4.09 2.94

12/20/2010 5045-TRAN-H4 0.365 0.0252 6.14 3.79 75.4 0.770 2431 10.4 4.15 2.96

12/20/2010 5045-TRAN-H5 0.409 0.0225 5.91 3.74 75.3 1.04 2356 11.0 4.29 3.00

 Average 0.535 0.0296 6.04 3.60 91.6 1.42 2447 11.3 4.13 2.96

 c.o.v. 49% 39% 2.1% 4.3% 30% 65% 2.4% 16% 2.4% 0.97%
Mr. Joseph Bachman 

USEPA Headquarters 

April 13, 2011 

Page 17 of 20 

Draft Report 03-15847 WA 1104 

TABLE 31. TEST RESULTS FOR 1660-HD-08 USING CONFIGURATION 

3.1 OVER 55 MPH STEADY-STATE CYCLE 

Test Date Test Name 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

12/21/2010 5045-55_H6 0.0240 0.00246 1.70 0.573 11.4 0.000 1138 1.91 8.89 9.14

12/21/2010 5045-55-H7 0.0299 0.00216 1.71 0.681 10.8 0.000 1111 2.40 9.10 9.15

12/21/2010 5045-55-H8 0.0345 0.00183 1.72 0.675 11.3 0.000 1121 1.93 9.02 9.20

12/21/2010 5045-55-H9 0.0283 0.00262 1.72 0.620 10.7 0.000 1091 1.69 9.27 9.14

12/21/2010 5045-55-H10 0.0273 0.00232 1.74 0.658 11.1 0.000 1115 1.94 9.07 9.17

 Average 0.0288 0.00228 1.72 0.641 11.1 0.000 1115 1.97 9.07 9.16

 c.o.v. 13% 13% 0.80% 7.0% 2.6% 0.00% 1.5% 13% 1.5% 0.28%

TABLE 32. TEST RESULTS FOR 1660-HD-08 USING CONFIGURATION 

3.1 OVER 65 MPH STEADY-STATE CYCLE 

Test Date Test Name 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

12/20/2010 5045-65-H1 0.0262 0.000 2.26 0.905 12.8 0.0539 1306 4.4166 7.74 10.8 

12/20/2010 5045-65-H2 0.0288 0.000 2.21 0.903 12.8 0.0628 1314 4.2253 7.69 10.9 

12/20/2010 5045-65-H3 0.0353 0.000 2.23 0.785 15.2 0.0604 1310 4.3666 7.72 10.9 

12/20/2010 5045-65-H4 0.0312 0.000 2.28 1.01 12.6 0.0556 1294 4.2126 7.81 10.8 

12/20/2010 5045-65-H5 0.0649 0.000 2.18 0.794 11.7 0.0632 1275 1.5730 7.93 10.9 

 Average 0.0373 0.000 2.23 0.879 13.0 0.0592 1300 3.7588 7.78 10.8 

 c.o.v. 42% 0.00% 1.8% 11% 9.9% 7.1% 1.2% 33% 1.2% 0.14% 

3.0 SUMMARY 

Three heavy-duty, on-road tractors were delivered to SwRI for the purposes of measuring 

greenhouse gas emissions of each truck on a chassis dynamometer using various road load and test inertia 

configurations representative of common tractor-trailer combinations used in the US. Each truck 

configuration was hot-start tested over the transient cycle, shown in Figure 1, a ten minute, 55 mph 

steady-state cruise cycle, and a ten minute 65 mph steady-state cycle. The two, tandem-axle Class 8 

trucks were also tested for ten minutes at idle. Ten minutes of settling time preceded sampling of the 

steady-state tests and cruise control was used during the 55 mph and 65 mph tests. 

 The average emission and fuel economy results for the three configurations tested using 

Truck 1660-HD-01 over the EPA Transient cycle, 55 mph steady-state cycle, and the 65 mph 

steady-state cycle are shown in Tables 33 through 35, respectively. Emissions of CO2, NOx, NO 

and N2O and fuel economy were similar for each configuration for a given drive cycle, which 

was expected since the configuration test values were similar. With the exception of N2O, the 

concentrations of these emissions are much greater than the ambient or background 

concentrations, reducing their variability. 
Mr. Joseph Bachman 

USEPA Headquarters 

April 13, 2011 

Page 18 of 20 

Draft Report 03-15847 WA 1104 

TABLE 33. SUMMARY OF AVERAGE VALUES OF EACH CONFIGURATION FOR TRUCK 

1660-HD-01 OVER THE EPA TRANSIENT CYCLE 

Configuration 

Number 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

1.1 0.00765 0.0103 6.76 4.96 74.6 0.252 3166 1.27 3.19 2.96

1.2 0.0791 0.00640 7.37 4.85 50.9 0.105 3133 0.390 3.23 2.97

1.3 0.266 0.00852 6.89 3.38 57.1 0.167 3120 0.843 3.24 2.97

TABLE 34. SUMMARY OF AVERAGE VALUES OF EACH CONFIGURATION FOR TRUCK 

1660-HD-01 OVER THE 55 MPH STEADY-STATE CYCLE

Configuration 

Number 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

1.1 0.000 0.000 1.83 0.772 10.4 0.00327 1370 0.432 7.38 9.25

1.2 0.0175 0.000149 1.96 0.806 10.2 0.0000 1364 0.230 7.41 9.23

1.3 0.0158 0.000899 1.94 1.01 9.37 0.00329 1343 0.262 7.53 9.27

TABLE 35. SUMMARY OF AVERAGE VALUES OF EACH CONFIGURATION FOR TRUCK 

1660-HD-01 OVER THE 65 MPH STEADY-STATE CYCLE 

Configuration 

Number 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

1.1 0.000 0.0000 3.40 1.43 10.8 0.000 1449 0.548 6.98 10.84

1.2 0.0227 0.0000 3.47 1.79 11.2 0.000 1515 0.257 6.68 10.90

1.3 0.0131 0.0000 3.00 0.00 11.3 0.000 1468 0.245 6.89 10.84

Emissions of HC, CH4, CO, and PM are typically very low for heavy-duty, dieselpowered vehicles equipped with Diesel Particulate Filters (DPFs). It is not uncommon for the 

tailpipe exhaust sample concentration of these emissions to be either close to, or below, the 

background concentration. Because the sample concentration is close to the background 

concentration, the corrected values are very small and highly variable test-to-test. For example, 

the average PM value for Configuration 1.1 over the EPA Transient cycle is three times higher 

than the average value for Configuration 1.2. It is unlikely that the configuration differences 

were responsible for this large difference. It is more likely that the exhaust aftertreatment and 

measurement resolution were greater factors based on previous experience with this type of 

testing with similar vehicles. This discussion is meant to caution against drawing incorrect 

conclusions when comparing emission values with large test-to-test variation between 

configurations. 

 
Mr. Joseph Bachman 

USEPA Headquarters 

April 13, 2011 

Page 19 of 20 

Draft Report 03-15847 WA 1104 

The average emission and fuel economy results for the four configurations tested using Truck 

1660-HD-02A over the EPA Transient cycle, 55 mph steady-state cycle, and the 65 mph steadystate cycle are shown in Tables 36 through 38, respectively. The configurations tested on this 

truck varied more than configurations tested using Truck 1660-HD-01 and, as expected, the fuel 

economy varied more between configurations. 

The Configurations 2.1 and 2.2 were tested with lower test inertia than Configurations 2.3 

and 2.4, 66,750 lb. compared to 70,250 lb., resulting in better fuel economy over the transient 

cycles. Configuration 2.2 produced the worst fuel economy over the steady-state cruise cycles 

because it’s aerodynamic load coefficient was the highest despite being tested using the lower 

inertia value, since test inertia does not affect vehicle load at steady-state speeds. 

It was observed that the average N2O value for Configuration 2.4 was nearly twice as 

high as the other three configurations. N2O is formed by the catalysts in the aftertreatment and 

the formation of N2O is a function of catalyst temperature. During this project, it was common 

for the first test of test sequence to produce the most N2O due the catalysts not being fully 

warmed up which indicates that the catalyst temperatures for Configuration 2.4 were lower than 

they were for the other configurations. Catalyst bed temperatures were not recorded during this 

project, but the test cell temperature was five degrees Celsius lower for Configuration 2.4 

compared to the other configurations, which may explain why the N2O emissions were 

significantly higher than the other others over the EPA Transient cycle. 

TABLE 36. SUMMARY OF AVERAGE VALUES OF EACH CONFIGURATION FOR TRUCK 

1660-HD-02A OVER THE EPA TRANSIENT CYCLE 

Configuration 

Number 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

2.1 0.193 0.0186 6.36 3.07 68.6 0.406 2974 1.56 3.40 3.01

2.2 0.107 0.0107 6.80 3.41 69.9 0.164 2942 0.822 3.44 2.95

2.3 0.144 0.0134 6.19 3.02 73.2 0.232 3074 0.598 3.29 2.98

2.4 0.318 0.0120 7.05 3.80 122 0.650 3169 1.35 3.19 2.92

TABLE 37. SUMMARY OF AVERAGE VALUES OF EACH CONFIGURATION FOR TRUCK 

1660-HD-02A OVER THE 55 MPH STEADY-STATE CYCLE 

Configuration 

Number 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

2.1 0.0309 0.0029 1.24 0.418 9.30 0.0185 1175 0.329 8.61 9.20

2.2 0.0269 0.00111 1.60 0.633 9.29 0.00940 1396 1.38 7.24 9.17

2.3 0.0299 0.0000 2.15 0.724 9.24 0.0117 1355 0.288 7.46 9.21

2.4 0.0500 0.0000 2.55 0.901 10.0 0.0749 1368 0.309 7.39 9.19
Mr. Joseph Bachman 

USEPA Headquarters 

April 13, 2011 

Page 20 of 20 

Draft Report 03-15847 WA 1104 

This report shall not be reproduced, except in full, without the written approval of Southwest Research Institute®. 

Results and discussion given in this report relate only to the test items described in this report.

TABLE 38. SUMMARY OF AVERAGE VALUES OF EACH CONFIGURATION FOR TRUCK 

1660-HD-02A OVER THE 65 MPH STEADY-STATE CYCLE 

Configuration 

Number 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

2.1 0.0423 0.000 1.92 0.697 14.0 0.0111 1327 0.203 7.62 10.9

2.2 0.0860 0.000 4.45 1.46 12.5 0.00292 1627 0.224 6.21 10.8

2.3 0.139 0.000 3.15 1.20 11.6 0.000934 1594 0.411 6.34 10.9

2.4 0.0739 0.000 3.68 0.791 10.8 0.0582 1537 0.204 6.57 10.8

Truck 1660-HD-08 was only tested using one configuration. The average values for each 

cycle using the same configuration are summarized in Table 39. 

TABLE 39. SUMMARY OF AVERAGE VALUES FOR TRUCK 1660-HD-08 OVER THE EPA 

TRANSIENT, 55 MPH STEADY-STATE, AND 65 MPH STEADY-STATE CYCLES 

Drive Cycle 

HC, 

g/mile 

CH4, 

g/mile 

NOx, 

g/mile 

NO, 

g/mile 

N2O, 

mg/mile 

CO, 

g/mile 

CO2, 

g/mile 

PM, 

mg/mile 

Fuel 

Econ., 

MPG 

Distance, 

miles 

Transient 0.535 0.0296 6.04 3.60 91.6 1.421 2447 11.3 4.13 2.96

55 mph 0.0288 0.00228 1.72 0.641 11.1 0.000 1115 1.97 9.07 9.16

65 mph 0.0373 0.0000 2.23 0.879 13.0 0.0592 1300 3.76 7.78 10.8

Prepared by: Approved by: 

DRAFT DRAFT 

Joseph W. Anthony Vlad Ulmet 

Senior Research Engineer Manager 

Emissions Research and Development Emissions Research and Development 

 Department Department 

/mab 

EMISSIONS RESEARCH AND DEVELOPMENT DEPARTMENT 

 ENGINE, EMISSIONS, AND VEHICLE RESEARCH DIVISION