Hi all, first time on the forum so thanks in advance for your help! I just bought a 1997 Cherokee Country about 3 months ago. Its been driving perfect until the last few days.

There's a sound coming from the rear of the car when I drive over about 15mph, but only if I'm not accelerating. It sounds a lot like a flat tire, but I topped em all off and the sound remains. I recently noticed that at higher speed (60-80mph) the sound goes away after I've had my foot off the gas for a few seconds, but then my back end starts to feel loose. Any ideas?

A friend of mine suggested that I might just need to change the fluid in the rear diff. Is this a common problem?? I looked, but I didn't notice a drain or fill plug anywhere on there, did I just miss it??

Any help would be appreciated. I've never owned a Jeep before so I'm learning as I go.

 

did you check the lug nuts

 

Check your lug nuts first. If that doesn't do it, Try lubing the u-joints. If not that, change the diff fluid (might as well do both, oil and the transfer case at the same time. Just how I do it since it's gonna be laid up for an hour or so)..

 

Changing the diff fluid is pretty much the same in all solid axle vehicles. I suggest getting LubeLocker gaskets as they're reusable and make the job much easier. Pull off the differential cover by removing the bolts. It will usually be stuck on there pretty good due to the the gasket maker that's used by most people and the factory. Be careful prying off the cover that you don't warp or scratch it. Clean off the old RTV sealant and reassemble. If you got a LubeLocker gasket you'll need to follow the torque instructions that come with it. Fill with suggested lube (80w90 I believe or 75w140 if you tow) until it starts to seep out of the fill hole. If I remember correctly it took a bit over 2 quarts.

Even if it doesn't fix your issue going through all of the fluids when you purchase an 11 year old vehicle is a great idea. You should go through both diffs, transfer case, transmission, brake fluid, power steering fluid, coolant, and engine oil. For the diffs, you can use a vacuum tool to suck the old fluid out and refill, but taking the cover off gives you a chance to check the gears and clean out the sludge in the bottom of the diff.

 

i dont suggest prying at all, it risks warping it, tap it with a rubber mallet

 

X2 on the lugs torq em down 100ftlbs and swaping diff fluid is easy and there is no dran plug you just pry off the cover GENTLY and have your catch pan ready and the fluid will come right out then inspect for metal shavings then blast all in there with brake cleaner then just put on the cover and fill her up and if your doing both front and rear with a 8.25/30 buy 5 quarts and you will be golden

 

http://www.4x4xplor.com/diff-service.html

its pretty straight forward. make sure everythings cool with your driveshaft, and do grease stuff.

 

TIres out of balance??? Your diff plug is there just clean off the sludge and you will find it lol.

 

Thanks for the replies all! I ended up at a gas station mechanic the day after I posted. Unfortunately since I've always had sports cars, I didn't have a jack that would like the Cherokee or I would have found the problem myself! Turns out one of the lug nuts was gone, so the 1 wheel stud snapped off, bent another, and the entire wheel was just bouncing on the hub! Since it went for so long, it ruined the stud whole in the wheel itself so I was on the spare donut for a few days until I could get another wheel! Bought 2 while i was at it so I have a full size spare for next time!

 

lucky you didn't crash