So i have been chasing this noise that sounds like a bad front hub bearing for about a month now. At 35-45 mph this "roaring" noise occurs, and at 60+ the noise level in the cabin is ridiculous. I recently changed both front hub assemblies, but that did not resolve the issue. It's a 2wd 01 sport with 192k. Now I'm about to tackle the ball joints (all of them) but what else should I replace while I'm down there? Tie rod ends? Any advice is appreciated?

 

Is there fluid in your rear diff?

 

Yeah, the rear diff is full and the fluid appears to be fine.

 

Roaring is not usually associated with ball joints. Roaring usually is associated with rotating parts (fans, transmissions, motors, hubs, bearings, differentials (anything with spinning gears).

If the roar continues after shifting into N at speed (when the sound is occurring), then that will isolate it down to only those parts that continue spinning (because they are connected to the wheels on the ground). This would include rear wheel bearings (most likely candidate by the way), differentials, front axle u-joints, drive shaft u-joints.

 

Have you had someone crawl around in jeep while you are driving to listen for noise location ? and yes.. rear axle bearing could be it.. jack up .. put on jack stands.. and then spin them up to speed they make noise and go from side to side and see if one of them is roaring..

 

I haven't had someone crawl around yet, but i will give that a shot. I imagine the rear bearings being much more difficult than the fronts (and I'm deathly afraid of drum brakes), but I'll check those out and update.

 

The rear bearings aren't much harder than the fronts. Just different. Plenty of videos for XJ rear bearing work on youtube. Depending on your axle, you'll probably have to open the rear differential. Which is tedious but not difficult at all. Plenty of videos on that as well.

You can typically service the rear wheel bearings without messing with the drum brakes at all. Take your rear wheel off today and have a look, you might realize its not so bad.

Lastly, buckle down and service your drum brakes when you get a chance. After the first time you do them, I don't think they will ever intimidate you again. I put them off for a while as well, but after I finally did it, I can't believe I worried about it as much as I did.

 

if it turns out it is the rear outer axle bearing.. they make offset bearings encase the axle is pitted

 

Thanks, I appreciate that tidbit of info

 

what kind of tires do you have on it? do they feel smooth when you rub your hand along the tread or does it feel like a cheese grater?

 

I currently have some hankook 245/75/16's on. They are wearing evenly with no noticeable irregularities.

 

So while I was changing my rear wheel bearings, I removed the cross pin in the differential and one of the side gears fell out. I was able to fit it back in and get the gears to turn, but it is slightly misaligned and the pin won't go through both gears. The shafts are still in so none of the other gears shifted or fell. What do I do now? 01 2wd 8.25 diff

 

IDK if this is your case, but some diffs have shim washers behind the planet gears which can shift out of place when you pull the cross shaft. When I did my ZJ rear bearings, I stuck the cross shaft back in after pulling the c-clips so that wouldn't happen. I never checked the D35, but I got into this trouble with my GM 12-bolt Posi after busting the cross shaft. Too much torque!

 

Just make sure the gears are in and alighted properly for the pin to go back in.

 

Thanks for the replies guys. I got it back in there by rotating the gears with the pin removed. I held the gear that was opposite of the one that fell out in with my fingers. Once I found the position that allowed the pin to slide back through both of the gears, i rotated them back into alignment with the holes within the carrier. Sorry if that didn't make sense lol