The gross axle weight rating (GAWR) is the maximum distributed weight that may be supported by an axle of a road vehicle. Typically, GAWR is followed by either the letters FR or RR, which indicate front or rear axles respectively.
Road damage rises steeply with axle weight, and is estimated "as a rule of thumb... for reasonably strong pavement surfaces" to be proportional to the fourth power of the axle weight. This means that doubling the axle weight will increase road damage (2x2x2x2)=16 times.[1][2] For this reason trucks with a high axle weight are heavily taxed in most countries.
Examples of GAWR on common axles.
Axle | GAWR (Max) | Manufacturer |
---|---|---|
Dana 30 | 2,770 lbs | Dana Corp. |
Dana 35 | 2,770 lbs | Dana Corp. |
Dana 44 | 3,500 lbs | Dana Corp. |
Dana 50 | 5,000 lbs | Dana Corp. |
Dana 60 | 6,500 lbs | Dana Corp. |
Dana 70 | 10,000 lbs | Dana Corp. |
Dana 80 | 11,000 lbs | Dana Corp. |
Dana S 110 | 14,706 lbs | Dana Corp. |
Ford 9-inch axle | 3,600 lbs | Ford Motor Company |
Ford 8.8 axle | 3,800 lbs | Visteon |
Sterling 10.5 axle | 9,750 lbs | Visteon |
10.5" Corporate 14 Bolt Differential | 8,600 lbs | American Axle |
11.5 AAM | 10,000 lbs | American Axle |
10.5 AAM | 9,000 lbs | American Axle |