Montana Owners Club - Keystone Montana 5th Wheel Forum - View Single Post

MacDR50 · 03-13-2009, 10:22 AM

A 2500 GM HD and a 3500 GM SRW are identical except for the spring package. I can't speak for other brands but I suspect the same is true. The biggest limiting factor on loading the stock GM 2500 is the 245 tires which have only a 3015# capacity. The dually is the same truck with the same capacity axle and spring set as the 3500SRW. The load difference is the two extra tires. No extra brakes. The big difference is the sideways stability of those two extra tires. This is really important for TT's but less so for 5th wheels as they exert their sway at a point forward of the rear axle and do not have the leverage of the distance from the hitch point and the centre of the rear axle that the TT's do. Rear sag can be controlled with airbags or Timbrens or the installation of a helper spring. Sway can be reduced by insuring that the PIN weight is about 20% of the actual trailer weight. Buy a brake controller with a boost option so that the trailer brakes come on a bit before and a bit more than the TV's.

03-13-2009, 10:22 AM	#16
MacDR50 Montana Fan Join Date: Sep 2007 Location: St Johns Posts: 434 M.O.C. #7691	A 2500 GM HD and a 3500 GM SRW are identical except for the spring package. I can't speak for other brands but I suspect the same is true. The biggest limiting factor on loading the stock GM 2500 is the 245 tires which have only a 3015# capacity. The dually is the same truck with the same capacity axle and spring set as the 3500SRW. The load difference is the two extra tires. No extra brakes. The big difference is the sideways stability of those two extra tires. This is really important for TT's but less so for 5th wheels as they exert their sway at a point forward of the rear axle and do not have the leverage of the distance from the hitch point and the centre of the rear axle that the TT's do. Rear sag can be controlled with airbags or Timbrens or the installation of a helper spring. Sway can be reduced by insuring that the PIN weight is about 20% of the actual trailer weight. Buy a brake controller with a boost option so that the trailer brakes come on a bit before and a bit more than the TV's.