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Can't roll on

First time listener, first time caller. I have a '96 jeep grand charokee Laredo with what I’ve been told is a bad differential. The bearings and gears are all shot, but can’t afford to get a new one. I have taken off the front driveshaft to try and make it drivable again, but it is still making the grinding noise it was before. As well as catching real bad. Just wondering if I need to bother with it, or even attempt anything further.

A used one is an option, but was trying to get by as long as possible to save money.

You do not get Tom and Ray on this forum. What you do get is an assortment of people (DIYers, mechanics, etc) who try to help as much as possible.

I would not go too far from home or drive at high speeds with it. It’s always possible that something could disentegrate and this could be an inconvenience at the least or a safety issue at worst.
Your best option would be to find a used differential from the salvage yard or maybe on Craigslist, etc. Grinding and catching usually means you’re at the point where it may not go much longer.

Have you considered consulting a mechanic?

You have 2 differentials, which one is bad the front or rear? Assuming it is the front, since you disconnected the front drive shaft, the differential will still turn because the wheels are turning. Therefore you will still get all that noise.

You could buy mechanical disconnect front hubs, but that would cost money you don’t have. Better that money go into getting a used differential from a salvage yard. A used differential shouldn’t be all too expensive and this isn’t a difficult change out as far as labor costs. Some salvage yards even offer to the whole job at a fair price. Start calling salvage yards and have the car info; motor, transmission, and VIN # handy when you make the call.

All very helpful. It is for sure the front differential, and I haven’t driven it for a couple weeks. The mechanic said that all bearings and gears were bad and he would charge 800 bucks to fix it, including the used differential. I’d rather do the work myself and save some $ since the one closest to where I live was 300-500$. Haven’t found anything cheaper.

I was thinking maybe getting individual bearings and years and such that it could be cheaper. Good idea?

Getting the gears in a differential to mesh properly is not something for a DIY mechanic unless they are very experienced. You use shims and measurements to get everything lined up properly if you disassemble and reassemble a differential. Making a mistake means doing the job a second time and you’ll be in for more than what a mechanic would charge to do it right the 1st time. Save money with DIY oil changes, new batteries, and brake jobs. This one I’d leave it to a mechanic.

I’ve done this before more than a couple of times. Trying to DIY a differential rebuild is an operation in futility unless you have dial indicators and other high-precision tools. Proper gear mesh is highly important to proper operation.

But, swapping a used rear-end is do-able. And would be cheaper in the long run.

Yep, only option here is find one at a junkyard/auto recyler and swap it out. Actually shouldn’t be too expensive. I did that to my '72 Duster (rear axle) years ago in the parking lot of my dorm, it’s really pretty straight forward. You do NOT want to try repairing one.

Agree with UncleTurbo and BustedKnuckles. My Wrangler is mechanically similar to your Grand Cherokee, and the differentials are something that I will not touch on my own. I’m lucky to have an old school mechanic who “enjoys” the precision and challenge of that kind of work (his words), so when the time came for my rear end after about 175,000 miles I was glad to have him do it. The gears were fine but he replaced all the bearings and one axle shaft. But as you’ve found, good axle work comes at a price.

You have a couple of options here. One, as you’ve found, is to find a used set of gears and have them installed by a good mechanic. Another option might be to find a whole other front end with (presumably) good gears, and swap front axles. But you’re getting into a lot of other work, including steering linkages, suspension, and brake lines. Lots of work.

I’ll defer to the experts here, but as a total bare bones cheap “fix,” can the OP just remove the u-joints at the front wheels? Don’t try this at home until someone who knows better weighs in. Of course, I cringe suggesting this, but if it “gets you by” until you can repair it right… Edit: Read again, you say all the bearings are bad too, so maybe this won’t work…

By the way, while you’re at it, check the fluid level in the rear end so you don’t get a repeat back there…