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Some differential and CV joint questions

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I'm upgrading my xt6. it's looking like I'm going to be adding about 100hp. I'm trying to keep the Air-ride system that came stock on the vehicle, so I'm splicing differential internals and such in an attempt to keep my stock axles and such.


Now, I'm not a mechanic by any means, so I really don't know much about CV joints and differential internals.


So I'm curious about the durability of CV joints when put under "above-stock" stress. Should it be as simple as replacing the CV joints with new OEM XT6 joints, re-booting them and then running them like that?


Should I look at keeping the stock axles but using different CV joints? and then is this even an option? I know that the XT6 has virtually no after market support, so I know that whatever I look at doing would require a bit of research to make a custom application work, but once again, only if it's even an option.


Now on to differentials. I've picked up internals for a 4.44 mechanical rear LSD but I didn't grab the Pumpkin for this differential as shipping would become atrocious, and also because I'm hoping to swap the internals into the casing that came stock on my '89 xt6 (it was a 3.9 factory LSD) this way I should still be able to use stock axles. Anyway, can anyone comment on the feasibility of such a swap?


Any help will be greatly appreciated!



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i'd just run the stock axles, they are very robust and unlikely to have issues.  and if they do you'll likely have plenty of signs and warnings, they aren't likely to explode or fail catastrophically as long as they're not aftermarket axles (in which case i have seen that happen...in an XT6 no doubt).


yeah the 4.44 ring gear just bolts to the LSD chunk like the 3.9 does.  it'll go right in no problem, nothing really different about it.


the problem is you really want the same ring and pinion set matched to the case and side bearing retainers as they set the backlash and gear mesh properly and bearing preload....if you only swap the LSD chunk none of that changes. 


you're swapping the ring..or ring and pinion into a new case/pinion set/side diff retainer bearings, so all of that changes.


it is immensely critical on front diff bearings - mine just blew up in less than 10,000 miles when i set mine inadvertently wrong.  not sure if the rears are more tolerable obviously they're far smaller and not loaded as much/integrated to the trans...but i'd be sure to hear from the folks that really know this stuff well first.

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