The manufacturer specs says the 2002 Ram CTD set up with a 4.11 differential can tow 2,000 lbs more that the identical truck with a 3.55 read end. My truck has the 3.55 rear. If I went to the 4.11 gearing, then I’ve increased my towing capacity, right?? What about this … if I were to upgrade to a DTT or ATS tranny … would I then be safe to tow more than the manufacturer states?

I guess my main question is, what is the limiting component, the transmission or the rear end?

 

That is a good question, I have no answer though. The 3 gen trucks are the same way, 3.73's are 21,000 and 4.10's are 23,000.

It can't be the strength of the rear end because the higher gears (3.55's or 3.73's) are physicaly stronger then the low gears (4.10's)

Wouldn't think it would be the tranny either as it doesn't mater if you have the 6 speed or auto. Also a single wheel and dual wheel 1 ton have the same GCVW.

I think it may have more to do with being able to safely control you load, as the ability to get out of your own way.

Either way I am sure you would have no problem running your 3.55's at a 4.10 ratings, just might not pull the hills as good. My truck is rated for the 23,000 and I run it 30,000+

 

The weak link in the package has always been the trannies, the 4.10:1 Ratio give the truck more "mechanical advantage" than you get with the 3.54:1's or the now available 3.73:1's. It has nothing to do with the "strength" of the ring and pinion.

 

As long as you can start on a hill well, the lower neumerical ratios just mean that you shift on a hill sooner. I like my 2100 cruise on the freeway.