2023 Maryland Statutes › Transportation › Title 24 - Vehicle Laws -- Size, Weight, and Load; Highway Preservation › Subtitle 1 - Size, Weight, and Load › Section 24-109 - Gross Weight of Vehicles

(a)    (1)    In this section the following words have the meanings indicated.
(2)    “Single axle weight” means the total weight transmitted by all wheels whose centers may be included between 2 parallel transverse vertical planes 40 inches apart extending across the full width of the vehicle.
(3)    “Tandem axle weight” means the total weight transmitted to the road by 2 or more consecutive axles whose centers may be included between parallel vertical planes spaced more than 40 inches apart but not more than 96 inches apart extending across the full width of the vehicle.
(b)    An over–the–road bus or any vehicle that is regularly and exclusively used as an intrastate public agency passenger bus:
(1)    Is exempt from tandem axle weight limits provided in this section; but
(2)    Shall comply with the vehicle and combination of vehicles weight limits provided in this section that are not tandem axle weight limits.
(c)    Notwithstanding any other provisions of this title, the overall gross weight on a group of 2 or more consecutive axles may not exceed an amount produced by application of the following formula:
(            LN                              )
W = 500    (      ––––––––––––––    +     12N     +       36    )
(          N – 1                               )
where “W” = overall gross weight on any group of 2 or more consecutive axles to the nearest 500 pounds, “L” = distance in feet measured horizontally between the vertical centerlines of the extreme of any group of 2 or more consecutive axles, and “N” = number of axles in group under consideration, except that 2 consecutive sets of tandem axles may carry a gross load of 34,000 pounds each providing the overall distance between the first and last axles of such consecutive sets of tandem axles is 36 feet or more; provided, that such overall gross weight may not exceed eighty thousand (80,000) pounds, including any enforcement or statutory tolerances.
(d)    The following table indicates the permissible overall gross weights based upon the above formula:
Distance in
feet between
the extremes of
any group of 2
or more
consecutive
axles                      2 axles     3 axles     4 axles     5 axles     6 axles     7 axles
4                    34,000
5                    34,000
6                    34,000
7                    34,000
8
and less                34,000     34,000
More than
8                    38,000     42,000
75,000           39,000     42,500
10                    40,000     43,500
11                             44,000
12                             45,000      50,000
13                             45,500      50,500
14                             46,500      51,500
15                             47,000      52,000
16                             48,000      52,500      58,000
17                             48,500      53,500      58,500
18                             49,500      54,000      59,000
19                             50,000      54,500      60,000
20                             51,000      55,500      60,500     66,000
21                             51,500      56,000      61,000     66,500
22                             52,500      56,500      61,500     67,000
23                             53,000      57,500      62,500     68,000
24                             54,000      58,000      63,000     68,500      74,000
25                             54,500      58,500      63,500     69,000      74,500
26                             55,500      59,500      64,000     69,500
27                             56,000      60,000      65,000     70,000      75,500
28                             57,000      60,500      65,500     71,000      76,500
29                             57,500      61,500      66,000     71,500      77,000
30                             58,500      62,000      66,500     72,000      77,500
31                             59,000      62,500      67,500     72,500      78,000
32                             60,000      63,500      68,000     72,500      78,500
33                                            64,000      68,500     74,000      79,000
34                                            64,500      69,000     74,500      80,000
35                                            65,500      70,000     75,000
36                    Exception
See
subsection
(c),
This
section      (66,000)     70,500     75,500
37                                      (66,500)     71,000     76,000
38                                      (67,500)     72,000     77,000
39                                        68,000      72,500     77,500
40                                        68,500      73,000     78,000
41                                        69,500      73,500     78,500
42                                        70,000      74,000     79,000
43                                        70,500      75,000     80,000
44                                        71,500      75,500
45                                        72,000      76,000
46                                        72,500      76,500
47                                        73,500      77,500
48                                        74,000      78,000
49                                        74,500      78,500
50                                        75,500      79,000
51                                        76,000      80,000
52                                        76,500
53                                        77,500
54                                        78,000
55                                        78,500
56                                        79,500
57                                        80,000
(e)    The gross weight of any vehicle or combination of vehicles may not exceed the following limits:
Gross
Number of                              weight
axles                                  (in pounds)
Three or less                                                  55,000
Four                                                        66,000
Five as provided for in § 13–916 or § 13–923 of this
article                                                       80,000
(f)    A trailer with metal tires and a gross weight of more than 6,000 pounds may not be moved on a highway.
(g)    (1)    Except on interstate highways, a single unit vehicle with 3 axles, or a combination of vehicles with a trailer less than 32 feet long or a semitrailer less than 45 feet long, either registered as a farm vehicle or carrying farm products as defined under § 10–601 of the Agriculture Article that were loaded in fields or other off–highway locations, is permitted an axle load limit tolerance of 5% from subsections (c) and (d) of this section, except during harvest time when an axle load limit tolerance of 15% or, subject to paragraph (2) of this subsection, a gross vehicle weight tolerance of 5% from subsections (c) and (d) of this section is permitted for a vehicle carrying the following agricultural products:
(i)    Wheat, for the period from June 1 to August 15;
(ii)    Corn, for the period from July 1 to December 1;
(iii)    Soybeans, for the period from September 1 to December 31; and
(iv)    Vegetable crops, for the period from June 1 to October 31.
(2)    The harvest time gross vehicle weight limit tolerance of 5% under paragraph (1) of this subsection applies only to a vehicle traveling within 100 miles of the field or other off–highway location where the vehicle was loaded.
(3)    (i)    Except on interstate highways, a single unit vehicle with at least 3 axles or a combination of vehicles with a trailer length of less than 32 feet carrying forest products that have been loaded in forests or other similar off–highway locations is permitted an axle load limit tolerance of 10% from subsections (c) and (d) of this section, except for the period from June 1 through September 30 when an axle load limit tolerance of 15% from subsections (c) and (d) of this section is permitted.
(ii)    Except on interstate highways, a combination of vehicles with a semitrailer length of 45 feet or less carrying forest products that have been loaded in forests or other similar off–highway locations is permitted an axle load limit tolerance of 5% from subsections (c) and (d) of this section, except for the period from June 1 through September 30 when an axle load limit tolerance of 15% from subsections (c) and (d) of this section is permitted.
(h)    (1)    Any vehicle that uses an auxiliary power unit or an idle–reduction technology unit in order to promote reduction of fuel use and emissions from engine idling shall be allowed up to an additional 550 pounds total in gross, axle, tandem, or bridge formula weight limits.
(2)    To be eligible for the additional weight limit allowed under paragraph (1) of this subsection, the vehicle operator must:
(i)    Obtain and make available to law enforcement officers written certification of the weight of the auxiliary power unit or idle–reduction technology unit; and
(ii)    By demonstration or certification, prove that the idle–reduction technology unit is fully functional at all times.
(3)    The additional weight limit allowed under paragraph (1) of this subsection may not exceed the certified weight of the auxiliary power unit or idle–reduction technology unit.
(i)    Notwithstanding any other provision of this section, the gross vehicle weight of a vehicle for which a permit is issued under § 24–113.3 of this subtitle for traveling along a designated heavy weight port corridor may not exceed 100,000 pounds.