If a 2500 and 3500 are both HD models with the same cab and bed configuration and cummings diesel is there a reason to expect one to tow a 8000 lb 5th wheel better. By better I mean maintain 65mph up a steep hill.

Seems to me that the lighter 2500 with the same power would do a better job.

 

suspension and maybe frame and or brakes are heavier duty. not saying it would go faster but maybe be safer

 

I think the spring rates are the only difference in the two. They will both tow 8K with ease.

 

Also, there is no G in the word Cummins

 

I have read but I don't have any way to confirm it. That the only differance between a 2500 and a 3500 is spring rates and the rear of a 3500 has one more leaf spring.

 

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