WA Rev Code § 46.44.041 (2021)
2021 Revised Code of Washington|Title 46 - Motor Vehicles|Chapter 46.44 - Size, Weight, Load.|46.44.041 - Maximum gross weights—Wheelbase and axle factors.

RCW 46.44.041 Maximum gross weights—Wheelbase and axle factors.No vehicle or combination of vehicles shall operate upon the public highways of this state with a gross load on any single axle in excess of twenty thousand pounds, or upon any group of axles in excess of that set forth in the following table, except that two consecutive sets of tandem axles may carry a gross load of thirty-four thousand pounds each, if the overall distance between the first and last axles of such consecutive sets of tandem axles is thirty-six feet or more.The following table is based on the following formula: W = 500((LN/N-1)+12N+36). W is the maximum weight in pounds (to the nearest 500 pounds) carried on any group of two (2) or more consecutive axles. L is the distance in feet between the extremes of any group of two (2) or more consecutive axles. N is the number of axles under consideration.Distance in feet between the extremes of any group of 2 or more consecutive axles Maximum load in pounds carried on any group of 2 or more consecutive axles 2345 6 7 8 9axlesaxlesaxlesaxles axles axles axles axles          434,000        534,000        634,000        734,000        8 & less34,00034,000       more than 838,00042,000       939,00042,500       1040,00043,500       11 44,00049,000      12 45,00050,000      13 45,50050,500      14 46,50051,50056,500     15 47,00052,00057,000     16 48,00052,50058,000     17 48,50053,50058,500     18 49,50054,00059,00064,500    19 50,00054,50060,00065,000    20 51,00055,50060,50066,000    21 51,50056,00061,00066,50072,000   22 52,50056,50061,50067,00072,500   23 53,00057,50062,50068,00073,000   24 54,00058,00063,00068,50074,000   25 54,50058,50063,50069,00074,50080,000  26 55,50059,50064,00069,50075,00080,500  27 56,00060,00065,00070,00075,50081,000  28 57,00060,50065,50071,00076,50082,00087,500 29 57,50061,50066,00071,50077,00082,50088,000 30 58,50062,00066,50072,00077,50083,00088,500 31 59,00062,50067,50072,50078,00083,50089,000 32 60,00063,50068,00073,00078,50084,50090,000 33  64,00068,50074,00079,00085,00090,500 34  64,50069,00074,50080,00085,50091,000 35  65,50070,00075,00080,50086,00091,500 36  66,00070,50075,50081,00086,50092,000 37  66,50071,00076,00081,50087,00093,000 38  67,50071,50077,00082,00087,50093,500 39  68,00072,50077,50082,50088,50094,000 40  68,50073,00078,00083,50089,00094,500 41  69,50073,50078,50084,00089,50095,000 42  70,00074,00079,00084,50090,00095,500 43  70,50075,00080,00085,00090,50096,000 44  71,50075,50080,50085,50091,00096,500 45  72,00076,00081,00086,00091,50097,500 46  72,50076,50081,50087,00092,50098,000 47  73,50077,50082,00087,50093,00098,500 48  74,00078,00083,00088,00093,50099,000 49  74,50078,50083,50088,50094,00099,500 50  75,50079,00084,00089,00094,500100,000 51  76,00080,00084,50089,50095,000100,500 52  76,50080,50085,00090,50095,500101,000 53  77,50081,00086,00091,00096,500102,000 54  78,00081,50086,50091,50097,000102,500 55  78,50082,50087,00092,00097,500103,000 56  79,50083,00087,50092,50098,000103,500 57  80,00083,50088,00093,00098,500104,000 58   84,00089,00094,00099,000104,500 59   85,00089,50094,50099,500105,500 60   85,50090,00095,000100,500105,500 61   86,00090,50095,500101,000105,500 62   86,50091,00096,000101,500105,500 63   87,50092,00096,500102,000105,500 64   88,00092,50097,500102,500105,500 65   88,50093,00098,000103,000105,500 66   89,00093,50098,500103,500105,500 67   90,00094,00099,000104,500105,500 68   90,50095,00099,500105,000105,500 69   91,00095,500100,000105,500105,500 70   91,50096,000101,000105,500105,500 71   92,50096,500101,500105,500105,500 72   93,00097,000102,000105,500105,500 73   93,50098,000102,500105,500105,500 74   94,00098,500103,000105,500105,500 75   95,00099,000103,500105,500105,500 76   95,50099,500104,500105,500105,500 77   96,000100,000105,000105,500105,500 78   96,500101,000105,500105,500105,500 79   97,500101,500105,500105,500105,500 80   98,000102,000105,500105,500105,500 81   98,500102,500105,500105,500105,500 82   99,000103,000105,500105,500105,500 83   100,000104,000105,500105,500105,500 84    104,500105,500105,500105,500 85    105,000105,500105,500105,500 86 or more    105,500105,500105,500105,500When inches are involved: Under six inches take lower, six inches or over take higher. The maximum load on any axle in any group of axles shall not exceed the single axle or tandem axle allowance as set forth in the table above.The maximum axle and gross weights specified in this section are subject to the braking requirements set up for the service brakes upon any motor vehicle or combination of vehicles as provided by law.Loads of not more than eighty thousand pounds which may be legally hauled in the state bordering this state which also has a sales tax, are legal in this state when moving to a port district within four miles of the bordering state except on the interstate system. This provision does not allow the operation of a vehicle combination consisting of a truck tractor and three trailers.Notwithstanding anything contained herein, a vehicle or combination of vehicles in operation on January 4, 1975, may operate upon the public highways of this state, including the interstate system within the meaning of section 127 of Title 23, United States Code, with an overall gross weight upon a group of two consecutive sets of dual axles which was lawful in this state under the laws, regulations, and procedures in effect in this state on January 4, 1975.[ 2016 c 24 § 1; 1997 c 198 § 1; 1995 c 171 § 1. Prior: 1993 c 246 § 1; 1993 c 102 § 3; prior: 1988 c 229 § 1; 1988 c 6 § 2; 1985 c 351 § 3; 1977 c 81 § 2; 1975-'76 2nd ex.s. c 64 § 22.]NOTES:Effective date of 1993 c 102 and c 123—1993 sp.s. c 23: See note following RCW 46.16A.455.Effective dates—Severability—1975-'76 2nd ex.s. c 64: See notes following RCW 46.16A.455.