<< According to TM 9-2320-209-10-1
VEHICLE /BRIDGE CLASSIFICATION.
E - Class number of vehicle with no payload.
C - Class number of vehicle with cross-country payload.
H - Class number of vehicle with highway payload.
For a M35A2
E - 6
C - 8
H - 11
While the above is correct, I believe it is worthy of further explanation.... The bridge weight classification system is quiet complicated, varying for wheeled vehicles, tracked vehicles, spacing of axles, speed and number of lanes. I have several manuals on this subject, if anyone wants specifics, let my know and I'll try to supply them.
If you are ever on an active installation, you can note that bridges have classification numbers assigned to them. I say numbers, because there is one for tracked vehicles and one for wheeled vehicles. These can be seen at Ft. Campbell, Ft. Knox, and Ft. Riley, as well as others.
Similarly, vehicles have bridge weight classification numbers assigned to them, and each vehicles classification is listed in a number of manuals. And while there is often a direct relationship between the vehicles gross weight at the class number, it can occasionally vary due to, among other factors, speed and axle spacing. As examples, the M125 truck, with a weight empty of 14.39 tons, carries an empty bridge classification of 12, while a certain
wheeled tractor with a weight of 21.2 tons has a bridge class of 33.
The bridge weight classification numbers mounted on the front of Post-WWII US
military vehicles are as a rule changeable, and when properly operated they are changed, as noted above, depending upon how the vehicle is operated and loaded. The numerals should be changed depending upon load, further, the top plate has a red "C" on its flip side. When a vehicle is being used as a prime mover, that plate should be flipped and the numbers changed to reflect the COMBINATION bridge weight classification of the lash up. When the trailer is disconnected, the "C" should be hidden.
To make this even more difficult, you don't just add the weights, or even bridge classifications, to yield the COMBINATION bridge classification (remember axle spacing, etc., enters into this). As an example:
M270 low bed trailer empty weight 8.75 tons bridge classification 8
M246 tractor wrecker empty weight 16.42 tons bridge weight classification 15
Combination weight M246/M270 25.17 tons Combination weight classification 19
All of the above numbers are from TB 746-93-1,
View attachment gta 05-07-013 bridge plate.pdf
