Maximum gross weights — Wheelbase and axle factors.

RCW 46.44.041
in effect
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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 2 3 4 5 6 7 8 9 axles axles axles axles axles axles axles axles 4 34,000 5 34,000 6 34,000 7 34,000 8 & less 34,000 34,000 more than 8 38,000 42,000 9 39,000 42,500 10 40,000 43,500 11 44,000 49,000 12 45,000 50,000 13 45,500 50,500 14 46,500 51,500 56,500 15 47,000 52,000 57,000 16 48,000 52,500 58,000 17 48,500 53,500 58,500 18 49,500 54,000 59,000 64,500 19 50,000 54,500 60,000 65,000 20 51,000 55,500 60,500 66,000 21 51,500 56,000 61,000 66,500 72,000 22 52,500 56,500 61,500 67,000 72,500 23 53,000 57,500 62,500 68,000 73,000 24 54,000 58,000 63,000 68,500 74,000 25 54,500 58,500 63,500 69,000 74,500 80,000 26 55,500 59,500 64,000 69,500 75,000 80,500 27 56,000 60,000 65,000 70,000 75,500 81,000 28 57,000 60,500 65,500 71,000 76,500 82,000 87,500 29 57,500 61,500 66,000 71,500 77,000 82,500 88,000 30 58,500 62,000 66,500 72,000 77,500 83,000 88,500 31 59,000 62,500 67,500 72,500 78,000 83,500 89,000 32 60,000 63,500 68,000 73,000 78,500 84,500 90,000 33 64,000 68,500 74,000 79,000 85,000 90,500 34 64,500 69,000 74,500 80,000 85,500 91,000 35 65,500 70,000 75,000 80,500 86,000 91,500 36 66,000 70,500 75,500 81,000 86,500 92,000 37 66,500 71,000 76,000 81,500 87,000 93,000 38 67,500 71,500 77,000 82,000 87,500 93,500 39 68,000 72,500 77,500 82,500 88,500 94,000 40 68,500 73,000 78,000 83,500 89,000 94,500 41 69,500 73,500 78,500 84,000 89,500 95,000 42 70,000 74,000 79,000 84,500 90,000 95,500 43 70,500 75,000 80,000 85,000 90,500 96,000 44 71,500 75,500 80,500 85,500 91,000 96,500 45 72,000 76,000 81,000 86,000 91,500 97,500 46 72,500 76,500 81,500 87,000 92,500 98,000 47 73,500 77,500 82,000 87,500 93,000 98,500 48 74,000 78,000 83,000 88,000 93,500 99,000 49 74,500 78,500 83,500 88,500 94,000 99,500 50 75,500 79,000 84,000 89,000 94,500 100,000 51 76,000 80,000 84,500 89,500 95,000 100,500 52 76,500 80,500 85,000 90,500 95,500 101,000 53 77,500 81,000 86,000 91,000 96,500 102,000 54 78,000 81,500 86,500 91,500 97,000 102,500 55 78,500 82,500 87,000 92,000 97,500 103,000 56 79,500 83,000 87,500 92,500 98,000 103,500 57 80,000 83,500 88,000 93,000 98,500 104,000 58 84,000 89,000 94,000 99,000 104,500 59 85,000 89,500 94,500 99,500 105,500 60 85,500 90,000 95,000 100,500 105,500 61 86,000 90,500 95,500 101,000 105,500 62 86,500 91,000 96,000 101,500 105,500 63 87,500 92,000 96,500 102,000 105,500 64 88,000 92,500 97,500 102,500 105,500 65 88,500 93,000 98,000 103,000 105,500 66 89,000 93,500 98,500 103,500 105,500 67 90,000 94,000 99,000 104,500 105,500 68 90,500 95,000 99,500 105,000 105,500 69 91,000 95,500 100,000 105,500 105,500 70 91,500 96,000 101,000 105,500 105,500 71 92,500 96,500 101,500 105,500 105,500 72 93,000 97,000 102,000 105,500 105,500 73 93,500 98,000 102,500 105,500 105,500 74 94,000 98,500 103,000 105,500 105,500 75 95,000 99,000 103,500 105,500 105,500 76 95,500 99,500 104,500 105,500 105,500 77 96,000 100,000 105,000 105,500 105,500 78 96,500 101,000 105,500 105,500 105,500 79 97,500 101,500 105,500 105,500 105,500 80 98,000 102,000 105,500 105,500 105,500 81 98,500 102,500 105,500 105,500 105,500 82 99,000 103,000 105,500 105,500 105,500 83 100,000 104,000 105,500 105,500 105,500 84 104,500 105,500 105,500 105,500 85 105,000 105,500 105,500 105,500 86 or more 105,500 105,500 105,500 105,500 When 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. 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 2 3 4 5 6 7 8 9 axles axles axles axles axles axles axles axles 4 34,000 5 34,000 6 34,000 7 34,000 8 & less 34,000 34,000 more than 8 38,000 42,000 9 39,000 42,500 10 40,000 43,500 11 44,000 49,000 12 45,000 50,000 13 45,500 50,500 14 46,500 51,500 56,500 15 47,000 52,000 57,000 16 48,000 52,500 58,000 17 48,500 53,500 58,500 18 49,500 54,000 59,000 64,500 19 50,000 54,500 60,000 65,000 20 51,000 55,500 60,500 66,000 21 51,500 56,000 61,000 66,500 72,000 22 52,500 56,500 61,500 67,000 72,500 23 53,000 57,500 62,500 68,000 73,000 24 54,000 58,000 63,000 68,500 74,000 25 54,500 58,500 63,500 69,000 74,500 80,000 26 55,500 59,500 64,000 69,500 75,000 80,500 27 56,000 60,000 65,000 70,000 75,500 81,000 28 57,000 60,500 65,500 71,000 76,500 82,000 87,500 29 57,500 61,500 66,000 71,500 77,000 82,500 88,000 30 58,500 62,000 66,500 72,000 77,500 83,000 88,500 31 59,000 62,500 67,500 72,500 78,000 83,500 89,000 32 60,000 63,500 68,000 73,000 78,500 84,500 90,000 33 64,000 68,500 74,000 79,000 85,000 90,500 34 64,500 69,000 74,500 80,000 85,500 91,000 35 65,500 70,000 75,000 80,500 86,000 91,500 36 66,000 70,500 75,500 81,000 86,500 92,000 37 66,500 71,000 76,000 81,500 87,000 93,000 38 67,500 71,500 77,000 82,000 87,500 93,500 39 68,000 72,500 77,500 82,500 88,500 94,000 40 68,500 73,000 78,000 83,500 89,000 94,500 41 69,500 73,500 78,500 84,000 89,500 95,000 42 70,000 74,000 79,000 84,500 90,000 95,500 43 70,500 75,000 80,000 85,000 90,500 96,000 44 71,500 75,500 80,500 85,500 91,000 96,500 45 72,000 76,000 81,000 86,000 91,500 97,500 46 72,500 76,500 81,500 87,000 92,500 98,000 47 73,500 77,500 82,000 87,500 93,000 98,500 48 74,000 78,000 83,000 88,000 93,500 99,000 49 74,500 78,500 83,500 88,500 94,000 99,500 50 75,500 79,000 84,000 89,000 94,500 100,000 51 76,000 80,000 84,500 89,500 95,000 100,500 52 76,500 80,500 85,000 90,500 95,500 101,000 53 77,500 81,000 86,000 91,000 96,500 102,000 54 78,000 81,500 86,500 91,500 97,000 102,500 55 78,500 82,500 87,000 92,000 97,500 103,000 56 79,500 83,000 87,500 92,500 98,000 103,500 57 80,000 83,500 88,000 93,000 98,500 104,000 58 84,000 89,000 94,000 99,000 104,500 59 85,000 89,500 94,500 99,500 105,500 60 85,500 90,000 95,000 100,500 105,500 61 86,000 90,500 95,500 101,000 105,500 62 86,500 91,000 96,000 101,500 105,500 63 87,500 92,000 96,500 102,000 105,500 64 88,000 92,500 97,500 102,500 105,500 65 88,500 93,000 98,000 103,000 105,500 66 89,000 93,500 98,500 103,500 105,500 67 90,000 94,000 99,000 104,500 105,500 68 90,500 95,000 99,500 105,000 105,500 69 91,000 95,500 100,000 105,500 105,500 70 91,500 96,000 101,000 105,500 105,500 71 92,500 96,500 101,500 105,500 105,500 72 93,000 97,000 102,000 105,500 105,500 73 93,500 98,000 102,500 105,500 105,500 74 94,000 98,500 103,000 105,500 105,500 75 95,000 99,000 103,500 105,500 105,500 76 95,500 99,500 104,500 105,500 105,500 77 96,000 100,000 105,000 105,500 105,500 78 96,500 101,000 105,500 105,500 105,500 79 97,500 101,500 105,500 105,500 105,500 80 98,000 102,000 105,500 105,500 105,500 81 98,500 102,500 105,500 105,500 105,500 82 99,000 103,000 105,500 105,500 105,500 83 100,000 104,000 105,500 105,500 105,500 84 104,500 105,500 105,500 105,500 85 105,000 105,500 105,500 105,500 86 or more 105,500 105,500 105,500 105,500 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 2 3 4 5 6 7 8 9 axles axles axles axles axles axles axles axles 4 34,000 5 34,000 6 34,000 7 34,000 8 & less 34,000 34,000 more than 8 38,000 42,000 9 39,000 42,500 10 40,000 43,500 11 44,000 49,000 12 45,000 50,000 13 45,500 50,500 14 46,500 51,500 56,500 15 47,000 52,000 57,000 16 48,000 52,500 58,000 17 48,500 53,500 58,500 18 49,500 54,000 59,000 64,500 19 50,000 54,500 60,000 65,000 20 51,000 55,500 60,500 66,000 21 51,500 56,000 61,000 66,500 72,000 22 52,500 56,500 61,500 67,000 72,500 23 53,000 57,500 62,500 68,000 73,000 24 54,000 58,000 63,000 68,500 74,000 25 54,500 58,500 63,500 69,000 74,500 80,000 26 55,500 59,500 64,000 69,500 75,000 80,500 27 56,000 60,000 65,000 70,000 75,500 81,000 28 57,000 60,500 65,500 71,000 76,500 82,000 87,500 29 57,500 61,500 66,000 71,500 77,000 82,500 88,000 30 58,500 62,000 66,500 72,000 77,500 83,000 88,500 31 59,000 62,500 67,500 72,500 78,000 83,500 89,000 32 60,000 63,500 68,000 73,000 78,500 84,500 90,000 33 64,000 68,500 74,000 79,000 85,000 90,500 34 64,500 69,000 74,500 80,000 85,500 91,000 35 65,500 70,000 75,000 80,500 86,000 91,500 36 66,000 70,500 75,500 81,000 86,500 92,000 37 66,500 71,000 76,000 81,500 87,000 93,000 38 67,500 71,500 77,000 82,000 87,500 93,500 39 68,000 72,500 77,500 82,500 88,500 94,000 40 68,500 73,000 78,000 83,500 89,000 94,500 41 69,500 73,500 78,500 84,000 89,500 95,000 42 70,000 74,000 79,000 84,500 90,000 95,500 43 70,500 75,000 80,000 85,000 90,500 96,000 44 71,500 75,500 80,500 85,500 91,000 96,500 45 72,000 76,000 81,000 86,000 91,500 97,500 46 72,500 76,500 81,500 87,000 92,500 98,000 47 73,500 77,500 82,000 87,500 93,000 98,500 48 74,000 78,000 83,000 88,000 93,500 99,000 49 74,500 78,500 83,500 88,500 94,000 99,500 50 75,500 79,000 84,000 89,000 94,500 100,000 51 76,000 80,000 84,500 89,500 95,000 100,500 52 76,500 80,500 85,000 90,500 95,500 101,000 53 77,500 81,000 86,000 91,000 96,500 102,000 54 78,000 81,500 86,500 91,500 97,000 102,500 55 78,500 82,500 87,000 92,000 97,500 103,000 56 79,500 83,000 87,500 92,500 98,000 103,500 57 80,000 83,500 88,000 93,000 98,500 104,000 58 84,000 89,000 94,000 99,000 104,500 59 85,000 89,500 94,500 99,500 105,500 60 85,500 90,000 95,000 100,500 105,500 61 86,000 90,500 95,500 101,000 105,500 62 86,500 91,000 96,000 101,500 105,500 63 87,500 92,000 96,500 102,000 105,500 64 88,000 92,500 97,500 102,500 105,500 65 88,500 93,000 98,000 103,000 105,500 66 89,000 93,500 98,500 103,500 105,500 67 90,000 94,000 99,000 104,500 105,500 68 90,500 95,000 99,500 105,000 105,500 69 91,000 95,500 100,000 105,500 105,500 70 91,500 96,000 101,000 105,500 105,500 71 92,500 96,500 101,500 105,500 105,500 72 93,000 97,000 102,000 105,500 105,500 73 93,500 98,000 102,500 105,500 105,500 74 94,000 98,500 103,000 105,500 105,500 75 95,000 99,000 103,500 105,500 105,500 76 95,500 99,500 104,500 105,500 105,500 77 96,000 100,000 105,000 105,500 105,500 78 96,500 101,000 105,500 105,500 105,500 79 97,500 101,500 105,500 105,500 105,500 80 98,000 102,000 105,500 105,500 105,500 81 98,500 102,500 105,500 105,500 105,500 82 99,000 103,000 105,500 105,500 105,500 83 100,000 104,000 105,500 105,500 105,500 84 104,500 105,500 105,500 105,500 85 105,000 105,500 105,500 105,500 86 or more 105,500 105,500 105,500 105,500 When 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.
Source: WA Statutes (Official Site)URL: https://app.leg.wa.gov/RCW/default.aspx?cite=46.44&full=trueFetched: 6/29/2026

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