2008 Liberty Rear End Diff Swap

[eyestabbystab]

So, I've been told by a local mechanic that my rear end is going out. No other information. A weekend wrench buddy told me he thinks it more bearings etc.
Symptoms include: Very loud whirring sound when going forward, reverse at minimal speed; no sound.
No visible leaking around transfer case.
*Jeep has 220k+ miles. And I have abused it pulling trailers cross country. Never changed anything with rear end before.
As a gunho youtube watching woman......think I could swap the whole thing out with a junk yard rear diff? What all possible problems would swapping the entire thing fix?
*Did check oil, was a little low (had to stick finger pretty deep to hit oil) Oil was dark and smelled very burnt. Added more gear oil (80w90) but did not completely drain and put new. Wanted to see if adding more did anything at all.
If you have made it this far, thanks for reading my ridiculously long post. Guys please help!

 

[KJowner]

If you don't mind a bit of work then swap the whole axle out. This is the cheapest and easiest option. Just check you get the same ratio, the manuals, diesels and 2.4 KJs are different. Not sure what the score is with the KK.
The diff is setup for the axle it's fitted to so requires specialist tools to replace with another one, it's doable at home if you don't mind tooling up but expensive to buy all the kit for a one off.
If it's just bearings then that's also DIYable but you still need some hefty gear to undo and re torque the pinion and an inch pound torque wrench to set the preload. However you are likely to find a lot more wear in there when you start looking at the bits, so expect to buy more than just a set of bearings.
80w90 is a bit thin for the diff 140w is the recommended oil.
There are several post on here about diff repairs, have a read and see what you think.

 

[eyestabbystab]

If you don't mind a bit of work then swap the whole axle out. This is the cheapest and easiest option. Just check you get the same ratio, the manuals, diesels and 2.4 KJs are different. Not sure what the score is with the KK.
The diff is setup for the axle it's fitted to so requires specialist tools to replace with another one, it's doable at home if you don't mind tooling up but expensive to buy all the kit for a one off.
If it's just bearings then that's also DIYable but you still need some hefty gear to undo and re torque the pinion and an inch pound torque wrench to set the preload. However you are likely to find a lot more wear in there when you start looking at the bits, so expect to buy more than just a set of bearings.
80w90 is a bit thin for the diff 140w is the recommended oil.
There are several post on here about diff repairs, have a read and see what you think.

Thanks so much! Enough said, it's going to the mechanic lol

 

[AFT2008KK]

My 2 cents for what it’s worth. Get a full diagnosis. Then decide. Rear axle swaps aren’t impossible to do. Take your time. If going junkyard swap check out donor carefully. Don’t want to inherit another KK’s problems.

 

[lfhoward]

All the automatic transmission KK’s were 3.73 gear ratio in 2008. If you have a manual transmission it will be different. They were 3.23 IIRC.