Drive Shaft Lengths

[JYau]

I'm in the middle of converting my Jeep from 2WD to 4WD, I picked up some later model Cherokee axles that were already regeared to 4.56. The new rear axle is a Chrysler 8.25, the current one I have in there now is your typical D35. From what I've read on this site, is that the Chrysler 8.25 is about an inch closer to the t-case than the D35. Suggesting that a shorter drive shaft is required. 

My question is, is there enough slip in the drive shaft where it doesn't need to be shortened? My Comanche is a SWB and there is no lift in the rear, although it appears that my springs have no noticeable sag in them as well. Thanks!

[DirtyComanche]

You have a 4wd Comanche rear driveshaft for your engine/trans/tcase combination already?

 

Personally I would say to try installing it and see, but if it is too long and bottoms out in the tcase, you will destroy the tcase or other things, so if it is too long do not say "Eh, close enough" and drive it.  If the shaft is too long it is normally fairly economical to take them to a driveshaft shop and have them cut it down and balance it.  If it's too short it tends to cost a lot more, as they will need a new piece of tubing.

[Pete M]

for a stock truck, no.  you''ll need to shorten it or else risk bottoming out and damaging something.  on a lifted truck, maybe.  a 5" lift usually needs and extra inch of driveshaft so it'd balance out.

[pizzaman09]

Driveshaft length changes, particularly to be made shorter are pretty cheap.  I had two driveshafts for an F150 rebuilt and the one shortened just for about $140 locally.  That included all new Spicer U joints.

[JYau]

Thanks for all the suggestions. I do not yet have the 4WD drive shaft, I was hopeful that if I found one I could use that rather than getting a custom one made, or re-sizing the current one I have. Also, during the swap I thought it would be convenient to run the old rear axle while I prepped the new axle for install and it would all just bolt right up. I'll play it safe and get one at the right length.