UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

NATIONAL VEHICLE AND FUEL EMISSIONS LABORATORY

2000 TRAVERWOOD ROAD

ANN ARBOR, MI 48105-2498

 OFFICE OF

AIR AND RADIATION

July 18, 2011

MEMORANDUM

SUBJECT: Heavy-Duty Tire Evaluation

FROM: L. Joseph Bachman, Environmental Scientist

TO: Docket EPA-HQ-OAR-2010-0162

Background

EPA conducted two test programs to evaluate heavy-duty tires in coordination with the HeavyDuty Greenhouse Gas Emissions and Fuel Efficiency rulemaking, developed jointly with the 

National Highway Traffic Safety Administration (NHTSA). The first test program included a 

series of tire rolling resistance tests on medium- and heavy-duty vehicle tires. The second test 

program evaluated the correlation of tire rolling resistance and winter traction.

Summary of Analyses

Tire Rolling Resistance

EPA conducted a series of tire rolling resistance tests on medium- and heavy-duty vocational 

vehicle tires. The testing measured the coefficient of rolling resistance (RRC) of tires 

representing 16 different vehicle applications for Class 4 – 8 vocational vehicles. The testing 

included 2 to 13 samples each of both steer and drive tires for each application. The tests were 

conducted by two independent tire test labs, Standards Testing Lab (STL) and Smithers-Rapra 

(Smithers). 

Overall, a total of 156 medium- and heavy-duty tires were included in this testing, which was 

comprised of 88 tires covering various commercial vocational vehicle types, such as bucket 

trucks, school buses, city delivery vehicles, city transit buses and refuse haulers among others; 

47 tires intended for application to tractors; and 21 tires classified as LT tires intended for Class 

4 vocational vehicles such as delivery vans. In addition, approximately 20 of the tires tested 

were exchanged between the labs to assess inter-laboratory variability. 
2

The test results for 88 commercial vocational vehicle tires (19.5” and 22.5” sizes) showed a test 

average RRC of 7.4 kg/metric ton, with results ranging from 5.4 to 9.8 kg/metric ton. To comply

with the proposed vocational vehicle fuel consumption and GHG emissions standards using 

improved tire rolling resistance as the compliance strategy, a manufacturer would need to 

achieve an average tire RRC value of 8.1 kg/metric ton.

1

 The measured average RRC of 7.4 

kg/metric ton is thus better than the average value that would be needed to meet vocational 

vehicle standards. Of those eighty-eight tires tested, twenty tires had RRC values worse than 8.1

kg/metric ton, two were at 8.1 kg/metric ton, and sixty-six tires were better than 8.1 kg/metric 

ton. Additional data analyses examining the tire data by tire size to determine the range and 

distribution of RRC values within each tire size showed each tire size generally had tires ranging

from approximately 6.0 to 8.5 kg/metric ton, with a small number of tires in the 5.3 to 5.7 

kg/metric ton range and a small number of tires in a range as high as 9.3 to 9.8 kg/metric ton. 

Review of the data showed that for each tire size and vehicle type, the majority of tires tested 

would enable compliance with vocational vehicle fuel consumption and GHG emission 

standards. 

The test results for the 47 tires intended for tractor application showed an overall average of 6.9 

kg/metric ton, the lowest overall average rolling resistance of the different tire applications 

tested.

2

This is consistent with what the agencies heard through comments and meetings with tire 

suppliers whose efforts have focused on tractor applications, particularly for long-haul 

applications, which yield the highest fuel efficiency benefits from LRR tire technology. 

Finally, the 21 light truck (LT) tires intended for Class 4 vocational vehicles were comprised of 

two sizes; LT225/75R16 and LT245/75R16 with 11 and 10 samples tested, respectively. Some 

auto manufacturers have indicated that RRC values for tires fitted to these Class 4 vehicles 

typically have a higher RRC values than tires found on commercial vocational vehicles because 

of the smaller diameter wheel size and the ISO testing protocol.3The test data showed the

average RRC for LT225/75R16 tires was 9.1 kg/metric ton and the average for LT245/75R16 

tires was 8.6 kg/metric ton. The range for the LT225/75R16 tires spanned 7.4 to 11.0 kg/metric 

ton4and the range for the LT245/75R16 tires ranged from 6.6 to 9.8 kg/metric ton. Overall, the 

average for the tested LT tires was 8.9 kg/metric ton.

Analysis of the EPA test data for all vocational vehicles, including LT tires, shows the test 

average RRC is 7.3 kg/metric ton with a standard deviation of 1.2 kg/metric ton. Review of the 

data thus shows that for each tire size and vehicle type, there are multiple tires available that 

would enable compliance with the standards for vocational vehicles (which are predicated on 

tires with an RRC of 7.7 kg/metric ton), except for LT tires for Class 4 vocational vehicles where 

test results show the majority of these tires have RRC values greater than 8.1 kg/metric ton.

Subsequent to the testing, EPA and NHTSA reviewed the tires offered by tire manufacturers for 

recreational vehicles and emergency vehicles because these were not vocations that were 

specifically evaluated in the tire rolling resistance test program. The agencies found that 14 tires

 

1

See 75 FR at 74244.

2 The RRC values for these applications ranged from 5.4 to 9.2 kg/metric ton.

3

See comments to docket EPA-HQ-OAR-2010-0162-1761; Ford Motor Company

4 The agency notes the highest RRC values recorded for LT tires, of 11.0 and 10.9 kg/metric ton, were for two tires 

of the same size and brand. The nearest recorded values to these two tires were 9.8 kg/metric ton; substantially 

beyond the differences between other tires tested.
3

which are recommended for recreational vehicles and 8 tires recommended for emergency

vehicles were evaluated in the test program, as shown in Appendix B.

The agencies also reviewed the RRC data from the tires that were tested at both the STL and 

Smithers laboratories to assess inter-laboratory and test machine variability. The agencies 

conducted statistical analysis of the data to gain better understanding of lab-to-lab correlation 

and developed an adjustment factor for data measured at each of the test labs. When applied, 

this correction factor showed that for 77 of the 80 tires tested, the difference between the original 

RRC and a value corrected RRC was 0.01 kg/metric ton. The remaining three tires differed by

0.03, 0.05,and 0.07 kg/metric ton. Based on these results, the agencies believe the lab-to-lab 

variation for the STL and Smithers laboratories would have very small effect on measured RRC

values. Further, in analyzing the data, the agencies considered both test measurement variability

and the value of the measurements relative to proposed standards. The agencies concluded that 

although lab-to-lab and machine-to- machine measurement variability exists, the level observed 

is not excessive relative to the distribution of absolute measured RRC performance values and 

relative to the proposed standards. The agencies are making some revisions to the vehicle 

standards, but, based on this data, they concluded that the test protocol is reasonable for this 

program.

Winter Traction Test

U.S. EPA contracted with Smithers Rapra North America, Inc. to conduct a variety of tests on a 

group of 27 medium-duty truck tires.5The testing included: 

 Driving traction on snow 

 ISO 20580 rolling resistance 

 Physical measurements 

 Measurements of tire contact (footprint) geometry

One goal of this program was to determine whether there was any significant correlation between 

rolling resistance performance of typical-use truck tires and their winter driving traction 

performance. The tires were chosen to include a mixture of traction and long haul tires, with both 

SmartWay and non-SmartWay tires represented. Seven tire manufacturers participated in this 

program. The tires were provided by the manufacturers, with each manufacturer providing two to 

five tire models for testing. 

All tires in this program were either size 295/75R22.5 or 275/80R22.5 and all were load range G. 

Different physical tires were used for the traction testing than for the rest of the testing. 

To prevent any concerns over use of these data for commercial purposes, the data in this report 

have been blinded. Each tire specification in the program has been assigned a random code 

number. The same code number will be used to identify that specification for all of the tests. In 

that way, data from the various tests can be cross-plotted without the need to identify any 

specific tire brand or model. 

 

5

Smithers Rapra North America, Inc. “Dynamic Traction/Rolling Resistance.” June 6, 2011. Docket EPA-HQOAR-2010-0162.
4

The snow traction rating is the force needed to spin the test tire relative to the force needed to 

spin a control tire on a consistent prepared snow surface. Because this result is based on a 

specific control tire, the absolute values of the snow traction ratings from one test program 

cannot be easily compared with the values of snow traction ratings from a different test program. 

However, all other things being equal, higher values of the snow traction rating suggest that the 

tire has better traction performance. 

Overall group means and standard deviations are summarized as follows:

Snow traction rating (in percent):

Mean Standard deviation

Long Haul 100.4 12.2

SmartWay 100.7 12.7

Traction 134.8 11.4

Open Shoulder SmartWay 127.5 22.8

T-tests were calculated to evaluate group comparisons, with the following results:

Long Haul vs. SmartWay P = 0.956 (no significant difference)

Traction vs. Open Shoulder SmartWay P=0.5888 (no significant difference)

Long Haul vs. Traction P=0.0008

These suggest that although there is a significant difference between the closed shoulder “long

haul”/ “SmartWay” tires and the open shoulder tires designed for traction purposes, there is no 

statistically significant differences between the SmartWay and non-SmartWay verified tires in 

either category.

The relationship between the rolling resistance and snow traction is shown in Figure 1 below:
5

Figure 1: Rolling Resistance versus Snow Traction Rating

These data demonstrate that there is no statistically significant correlation between rolling 

resistance and the snow traction rating. Of the other measurements analyzed, the only relevant 

statistically significant correlations were between the gross and contact area and the snow 

traction rating and between the tread depth and rolling resistance coefficient. These observations 

lead EPA to believe that reductions in rolling resistance do not necessarily lead to reductions in 

snow traction performance.
Appendix A –Results of Vocational Vehicle Tire Testing

Lab 

conducting 

test Class Tire fitment Tire size

Load 

Range Position

Load, 

kg

Start Cold 

inflation 

pressure, 

kPa

Capped Hot 

inflation 

pressure, kPa

Rolling resistance 

force, kg-force, 

ISO28580, 2 m 

drum

Rolling resistance 

coefficient, kgforce/metric ton, 

ISO 28580, 2 m 

drum 

STL 4 City Delivery LT245/75R16 E Drive 1173 552 616 9.6 8.2

STL 4 City Delivery LT245/75R16 E Drive 1173 552 621 11.5 9.8

SRA 4 City Delivery LT245/75R16 E Drive 1173 550 627 11.4 9.8

SRA 4 City Delivery LT245/75R16 E Drive 1173 550 608 11.1 9.4

SRA 4 City Delivery LT245/75R16 E Drive 1173 550 610 10.0 8.5

SRA 4 City Delivery LT245/75R16 E Drive 1173 550 599 10.4 8.8

STL 4 City Delivery LT245/75R16 E Steer 1173 552 626 8.5 7.2

SRA 4 City Delivery LT245/75R16 E Steer 1173 550 621 7.8 6.6

SRA 4 City Delivery LT245/75R16 E Steer 1173 550 600 9.6 8.2

SRA 4 City Delivery LT245/75R16 E Steer 1173 550 612 11.5 9.8

STL 4 Conventional Van LT225/75R16 E Drive 1033 552 621 9.0 8.7

STL 4 Conventional Van LT225/75R16 E Drive 1033 552 616 9.2 8.9

SRA 4 Conventional Van LT225/75R16 E Drive 1033 550 632 9.6 9.3

STL 4 Conventional Van LT225/75R16 E Drive 1033 552 608 8.9 8.6

SRA 4 Conventional Van LT225/75R16 E Drive 1033 550 635 11.3 11.0

SRA 4 Conventional Van LT225/75R16 E Drive 1033 550 600 9.5 9.2

SRA 4 Conventional Van LT225/75R16 E Steer 1033 550 607 10.0 9.7

STL 4 Conventional Van LT225/75R16 E Steer 1033 552 621 7.7 7.4

SRA 4 Conventional Van LT225/75R16 E Steer 1033 550 613 11.1 10.8
7

STL4 Conventional Van LT225/75R16E Steer 1033 552 622 9.3 8.9

STL4 Conventional Van LT225/75R16E Steer 1033 552 637 7.9 7.6

STL4 Large Walk In 225/70R19.5F Drive 1403 655 750 12.5 8.9

STL4 Large Walk In 225/70R19.5F Drive 1403 655 749 11.2 8.0

STL4 Large Walk In 225/70R19.5G Steer 1531 758 836 10.3 6.7

STL4 Large Walk In 225/70R19.5F Steer 1403 655 743 8.6 6.1

STL4 Large Walk In 225/70R19.5F Steer 1403 655 754 11.3 8.1

STL4 Large Walk In 225/70R19.5F Steer 1403 655 756 9.9 7.1

STL4 Large Walk In 225/70R19.5G Steer 1531 758 876 10.9 7.1

STL4 Large Walk In 225/70R19.5F Steer 1403 655 736 9.6 6.9

SRA5 Bucket Truck 265/70R19.5 G Drive 2125 775 912 17.4 8.2

STL5 Bucket Truck 265/70R19.5G Drive 2125 758 871 17.1 8.1

STL5 Bucket Truck 245/70R19.5G Drive 1750 758 925 15.1 8.6

SRA5 Bucket Truck 265/70R19.5 G Drive 2125 760 881 13.8 6.5

SRA5 Bucket Truck 265/70R19.5 G Steer 2065 830 977 14.9 7.2

SRA5 Bucket Truck 265/70R19.5 G Steer 1955 760 874 13.4 6.8

SRA5 Bucket Truck 265/70R19.5 G Steer 2065 760 883 13.8 6.7

SRA5 City Delivery 245/70R19.5 G Drive 1904 760 872 11.3 5.9

SRA5 City Delivery 245/70R19.5 G Drive 1751 760 922 11.8 6.8

STL5 City Delivery 245/70R19.5G Drive 1750 552 678 14.1 8.1

STL5 City Delivery 245/70R19.5H Drive 1905 827 947 15.4 8.1

STL5 City Delivery 245/70R19.5H Drive 1905 793 900 14.6 7.6

STL5 City Delivery 245/70R19.5G Steer 1750 552 876 13.9 8.0

STL5 City Delivery 245/70R19.5H Steer 1905 827 934 13.0 6.8

STL5 City Delivery 225/70R19.5G Steer 1531 758 874 12.5 8.2
8

SRA5 City Delivery 245/70R19.5 H Steer 1904 830 957 11.9 6.2

SRA5 City Delivery 245/70R19.5 G Steer 1751 760 879 12.5 7.1

SRA5 City Delivery 245/70R19.5 F Steer 1573 660 758 11.5 7.3

SRA5 City Delivery 245/75R22.5 G Steer 1802 760 869 12.4 6.9

SRA5 City Delivery 245/70R19.5G Steer 1751 760 889 12.3 7.1

STL5 Large Walk-In 225/70R19.5G Drive 1531 758 856 11.3 7.4

STL5 Large Walk-In 225/70R19.5G Drive 1531 758 880 12.5 8.2

SRA5 Large Walk-in 225/70R19.5 F Drive 1403 660 762 11.5 8.2

SRA5 Large Walk-in 225/70R19.5 G Drive 1530 760 882 12.9 8.5

SRA5 Large Walk-in 225/70R19.5 F Drive 1403 660 764 12.3 8.7

SRA5 Large Walk-in 225/70R19.5 G Drive 1530 760 850 12.0 7.8

SRA5 Large Walk-in 245/70R19.5G Drive 1751 760 861 14.3 8.2

SRA5 Large Walk-in 245/70R19.5G Drive 1751 760 878 12.8 7.3

STL5 Large Walk-In 225/70R19.5F Steer 1403 655 773 10.6 7.5

STL5 Large Walk-In 225/70R19.5G Steer 1531 758 891 12.1 7.9

STL6

Large Delivery 

Truck 245/75R22.5G Steer 1803 758 855 13.5 7.5

STL6

Large Delivery 

Truck 295/75R22.5G Drive 2381 758 858 20.7 8.7

SRA6 School Bus 10R22.5 G Drive 2189 790 914 17.0 7.8

SRA6 School Bus 10R22.5 G Drive 2189 790 918 18.0 8.2

STL6 School Bus 10R22.5G Drive 2188 793 872 15.4 7.0

STL6 School Bus 10R22.5G Drive 2188 793 902 19.2 8.8

STL6 School Bus 10R22.5G Steer 2188 793 907 15.3 7.0

STL6 School Bus 10R22.5G Steer 2188 793 901 14.4 6.6

SRA6 School Bus 10R22.5 F Steer 2006 690 797 11.6 5.8
9

SRA6 School Bus 10R22.5 G Steer 2189 790 918 16.1 7.3

SRA6 School Bus 10R22.5G Steer 2189 790 912 13.9 6.3

STL6 Single Axle Van 10R22.5F Drive 2007 690 803 16.3 8.1

SRA6 Single Axle Van 9R22.5F Drive 1751 720 819 14.3 8.2

STL6 Single Axle Van 9R22.5G Drive 1750 724 841 16.5 9.4

STL6 Single Axle Van 10R22.5F Drive 2007 690 798 16.9 8.4

STL6 Single Axle Van 10R22.5G Drive 2188 793 900 16.1 7.4

STL6 Single Axle Van 9R22.5F Steer 1750 724 794 9.9 5.7

STL6 Single Axle Van 9R22.5F Steer 1750 724 821 11.8 6.8

STL6 Single Axle Van 9R22.5F Steer 1750 724 803 11.7 6.7

STL6 Single Axle Van 9R22.5F Steer 1750 724 810 11.2 6.4

STL6 Single Axle Van 9R22.5G Steer 1750 724 839 13.8 7.9

SRA7 City Transit Bus 12R22.5H Drive 3017 830 995 23.5 7.8

SRA7 City Transit Bus 12R22.5 H Drive 2848 830 960 21.5 7.6

STL7 City Transit Bus 12R22.5H Drive 2850 827 950 24.0 8.4

STL7 City Transit Bus 12R22.5H Drive 3019 848 985 28.0 9.3

STL7 City Transit Bus 12R22.5H Steer 2850 827 969 20.7 7.3

SRA7 City Transit Bus 12R22.5 H Steer 2848 830 960 19.3 6.8

SRA7 City Transit Bus 12R22.5 H Steer 2848 830 969 18.7 6.6

SRA7 City Transit Bus 12R22.5H Steer 2848 830 951 16.6 5.8

SRA7 City Transit Bus 12R22.5H Steer 2848 830 962 18.4 6.5

SRA7 Large Delivery 11R22.5 G Drive 2380 720 859 22.2 9.3

SRA7 Large Delivery 11R22.5 G Drive 2380 720 840 19.9 8.4

SRA7 Large Delivery 11R22.5G Drive 2380 720 819 15.5 6.5

STL7

Large Delivery 

Truck 11R22.5G Drive 2381 724 836 23.2 9.8
10

STL7

Large Delivery 

Truck 275/80R22.5G Drive 2381 758 864 14.0 5.9

STL7

Large Delivery 

Truck 11R22.5H Drive 2549 827 952 20.7 8.1

SRA7 Large Delivery 11R22.5 G Steer 2380 760 880 14.1 5.9

STL7

Large Delivery 

Truck 11R22.5H Steer 2549 827 953 18.2 7.2

STL7

Large Delivery 

Truck 11R22.5G Steer 2381 724 831 16.7 7.0

SRA7 Large Delivery 11R22.5 G Steer 2380 720 861 19.0 8.0

SRA7 Large Delivery 11R22.5 H Steer 2550 830 980 19.0 7.4

SRA7 Medium Tractor 11R24.5 G Drive 2550 720 832 20.5 8.1

SRA7 Medium Tractor 11R24.5 H Drive 2763 830 963 21.5 7.8

SRA7 Medium Tractor 11R24.5 G Drive 2550 720 835 21.5 8.4

STL7 Medium Tractor 11R24.5G Drive 2548 724 838 19.6 7.7

STL7 Medium Tractor 11R24.5H Drive 2761 827 996 23.7 8.6

SRA7 Medium Tractor 11R24.5 H Steer 2763 830 960 16.6 6.0

SRA7 Medium Tractor 285/75R24.5G Steer 2380 760 847 15.2 6.4

SRA7 Medium Tractor 11R24.5 G Steer 2550 720 829 15.3 6.0

SRA7 Medium Tractor 11R24.5 G Steer 2550 720 826 16.5 6.5

STL7 Medium Tractor 11R24.5H Steer 2761 827 936 16.1 5.8

STL7 Medium Tractor 11R24.5G Steer 2548 724 830 16.8 6.6

STL7 Refuse 315/80R22.5L Drive 3505 896 1069 26.3 7.5

STL7 Refuse 315/80R22.5L Drive 3401 896 1014 26.4 7.8

STL7 Refuse 315/80R22.5L Drive 3856 896 1067 25.2 6.5

SRA7 Refuse 315/80R22.5 L Drive 3506 900 1042 22.9 6.5

SRA7 Refuse 315/80R22.5 M Drive 3859 900 1060 21.3 5.5
11

STL7 Refuse 315/80R22.5L Steer 3505 896 1053 21.4 6.1

STL7 Refuse 315/80R22.5J Steer 3189 827 977 19.2 6.0

SRA7 Refuse 315/80R22.5L Steer 3855 900 1080 23.9 6.2

SRA7 Refuse 315/80R22.5 L Steer 3859 900 1053 20.7 5.4

SRA8 Day Cab Regional 11R22.5G Drive 2380 720 826 16.7 7.0

STL8 Day Cab Regional 11R22.5G Drive 2381 724 849 20.8 8.7

STL8 Day Cab Regional 11R22.5G Drive 2381 724 867 19.4 8.1

SRA8 Day Cab Regional 11R22.5 H Drive 2550 830 975 21.6 8.5

STL8 Day Cab Regional 11R22.5G Steer 2381 724 838 16.4 6.9

SRA8 Day Cab Regional 11R22.5 G Steer 2380 760 872 16.0 6.7

SRA8 Day Cab Regional 11R22.5 G Steer 2380 720 833 14.9 6.2

SRA8 Day Cab Regional 11R22.5 H Steer 2550 830 951 15.8 6.2

SRA8 Day Cab-Regional 275/80R22.5G Steer 2380 760 862 16.8 7.0

SRA8 Day Cab-Regional 275/80R22.5G Steer 2380 760 860 13.5 5.7

SRA8 Long Haul 295/75R22.5G Drive 2380 760 873 19.3 8.1

SRA8 Long Haul 295/75R22.5 G Drive 2380 760 888 21.9 9.2

SRA8 Long Haul 275/80R22.5 G Drive 2380 760 872 19.1 8.0

SRA8 Long Haul 295/75R22.5 G Drive 2380 760 857 17.6 7.4

SRA8 Long Haul 275/80R22.5H Drive 2678 830 963 20.3 7.6

STL8 Long Haul 295/75R22.5G Drive 2381 758 865 15.7 6.6

STL8 Long Haul 295/75R22.5G Drive 2381 758 845 19.1 8.0

STL8 Long Haul 295/75R22.5G Drive 2381 758 832 18.6 7.8

STL8 Long Haul 295/75R22.5G Drive 2381 758 855 18.6 7.8

STL8 Long Haul 295/75R22.5G Steer 2381 758 838 13.3 5.6

STL8 Long Haul 295/75R22.5G Steer 2381 758 866 13.2 5.6

STL8 Long Haul 295/75R22.5G Steer 2381 758 835 14.9 6.2

SRA8 Long Haul 295/75R22.5 G Steer 2380 760 867 13.7 5.8
12

SRA 8 Long Haul 295/75R22.5 H Steer 2550 830 948 16.1 6.3

SRA 8 Long Haul 275/80R22.5 G Steer 2380 760 880 13.8 5.8

SRA 8 Long Haul 275/80R22.5 G Steer 2380 760 873 14.8 6.2

STL 8 On/Off Road 445/65R22.5 L Drive 4717 827 985 31.5 6.7

STL 8 On/Off Road 445/65R22.5 L Drive 4717 827 967 36.7 7.8

SRA 8 On/Off Road 425/65R22.5 L Drive 4377 830 995 32.1 7.4

SRA 8 On/Off Road 445/65R22.5 L Drive 4930 900 1066 28.2 5.7

STL 8 On/Off Road 445/65R22.5 L Drive 4717 896 1051 29.7 6.3

SRA 8 On/Off Road 445/65R22.5 L Steer 4760 830 996 30.0 6.3

SRA 8 On/Off Road 425/65R22.5 L Steer 4377 830 978 28.5 6.5

SRA 8 On/Off Road 445/65R22.5 L Steer 4930 900 1045 26.2 5.3

STL 8 On/Off Road 445/65R22.5 L Steer 4717 827 962 27.1 5.7

STL 8 On/Off Road 445/65R22.5 L Steer 4717 827 990 28.0 5.9
13

Appendix B – Results for Emergency Vehicle and Recreational Vehicle Tires

Emergency Vehicle Tires

Vehicle 

Class Tire Size

Load 

Range Manufacturer Design Position

RRc (kg/metric 

ton)

6 9R22.5 G Goodyear G149 RSA Steer 7.9

4 225/70R19.5 F Goodyear

G670 RV 

ULT Steer 7.1

5 245/70R19.5 G Goodyear G149 RSA Steer 8.0

6 9R22.5 G Goodyear G149 RSA Steer 7.9

6 10R22.5 G Goodyear G149 RSA Steer 7.0

6 245/75R22.5 G Goodyear G149 RSA Steer 7.5

7 315/80R22.5 L Goodyear G291 (LR"J") Steer 6.0

6 10R22.5 G Goodyear G124 Drive 8.1
14

Recreational Vehicle Tires

Vehicle 

Class Tire Size

Load 

Range Manufacturer Design Position

RRc (kg/metric 

ton)

4 225/70R19.5 F Goodyear G670 RV ULT Steer 7.1

4 225/70R19.5 G Michelin XZE Steer 6.7

4 225/70R19.5 F Michelin XZE Steer 6.9

5 245/70R19.5 G Michelin XZE Steer 6.8

6 9R22.5 F Michelin XZE Steer 6.7

5 245/70R19.5 H Continental HSR1 Steer 6.2

8 275/80R22.5 MICHELIN XZA3 Steer 5.8

5 265/70R19.5 MICHELIN XZE2+ Drive 6.5

7 /11R24.5 MICHELIN XZA3 Steer 6.0

6 /10R22.5 MICHELIN XZE Steer 7.3

8 275/80R22.5 MICHELIN XZE2 Steer 7.0

8 275/80R22.5 Continental HSR2 Steer 6.2

5 245/70R19.5 Continental HSR1 Steer 6.2

8 275/80R22.5 Continental HSR2 Steer 5.7