With the YJ axle you still have that box from the vacuum that you have to seal up. It is also a slightly beefier axle. When you have the 8.8 in the rear you can't do the waggy without lug pattern issues or getting custom shafts or running adapters. This is a good cheap upgrade if you have the time and skills to do it yourself.
Female rolling with the 93 YJ SOA Locked and Hard at Play
You can just as easily put the vacuum shift motor back on the CAD housing.. which will seal it back up.
My point is it's a better idea to figure out why he wants to swap it in.. if he blew an R&P for some reason maybe another d30 isn't a good idea.. better to get an idea of why hes entertaining the idea and guide from there.. sure it can be done, but should it be done is the question.
I tried searching and have come up empty handed, but im wondering if a xj axle will fit under my yj easily? I dont mind rewelding new spring perches.
I'm gonna take a wild stab in the dark and guess that your talking about replacing your rear axle.. I've heard of people swaping out there Turd35 in there YJ for a C8.25 and D44 out of a XJ.. Those would both work.. Now with that said there are better upgrades out there I think for the YJ rear such as the F8.8 for one example.. But both of those XJ rears will swap over. How much work goes into it exactly off the top of my head im not sure but it's there for you. Im not sure if you are looking for something with the same gearing as your front so you can install and go or are gonna regear both front and rear for perhaps a bigger set of tires your running..
__________________ -XJ- 2001 Jeep XJ Cherokee - Gone
1999 Jeep XJ Cherokee - Party Hard
-InfernoGirl- "They are the most fun you can have with your pants on..."