Looking at swapping my 1500 to 3/4 ton running gear (axles, springs, shocks etc.) Was wondering about the u-joint situation since i know a swb 2500 doesn't exist. Will I have to modify my driveshaft or is there an adapter? Reason i'd like to do this is for bigger tires and possibly lower gears. The truck's already 4wd, mostly concerned about rear driveshaft assuming i can re-use the front one from the 3/4 ton.

 

If anything, you will need to shorten your driveshaft.... and use a hybrid u-joint. The dana axle is goign to use larger joints. The front? May need to do the same thing.... measure and see.

 

You should be able to get a crossover joint for most anything. 1310/1330/1350 all combos are available.

The one wild card might be the weird 458 u-joint which seems to be a Dodge-only thing, but I don't think it will be an issue. And they stopped using it in 2000 at the rear pinion IIRC