help, grinding, vibration noise

[arctycfox]

95 XJ , i 've got a grinding sort of vibration, that i can't locate. Been coming and going for about 3 days, and now it's decided to stay. Before it on'y lasted bout 30 sec. or till the next time i even touched the brake pedal. I can take it in and out of gear, and no change. It doesn't vary with engine speed, but does with vehicle speed. It stil stops when I press the barake, no matter how lightly, but comes right back as soon as i let off. I thought it was coming from the front axle, but i can't seem to find anything wrong. Haven't checked the unit bearings yet though. Going to go pull it all apart AGAIN and check those now. Also how hot should a Trans. Case be after driving? Mine's real hot after driving 35 min. home. Found that out trying to figure this out. ANY help is appreciated.

Adam
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[arctycfox]

I've checked, ball joint's, brake calipers, pads, links, engine pulleys, belts.....

 

[Wiser]

stock? SYE. when i lifted mine it did that reall bad. i put a 2" tc drop and it went away

 

[arctycfox]

SYE, no drop. It's been fine for months now. this just started 3 days ago, and it's getting really bad.

 

[Wiser]

hhaha you got me.

 

[YELLAHEEP]

Check the u-joints in the front axle shafts. Bad unit bearings will make lots of noise before having any visible movement, but should be easy to tell if they're bad by removing all the brake parts, put it in neutral and give them a spin with your hand. It'll feel like it's full of gravel. Also, they don't generally get really hot under normal driving. If the hub nut area seems nuclear-hot, then I'd suspect the unit bearing.

 

[arctycfox]

does the Trans case get hot under normal conditions?

 

[arctycfox]

ok, looks like i may have blown the rear end or something. It's in the rear axle. Brakes all look good, but you can feel some sort of friction as you spin the shafts. Running to Vato-zone now to get some fluid and drain it to see. How do you get to those big honkin c-clips to remove the shafts?

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[arctycfox]

ok, I'm SCREWED!!! Set screw snapped off after coming 1/2" out. Can't put it back together, and can't get it apart! Now what!?

 

[arctycfox]

ok, got the set screw out. and I STILL can't find what wrong!! AND to add insult to injury, instead of shims to set the ring gear they use adjuster nuts, like Toyotas.....and of course they spun upon removal so now I can't just simply put it back together without setting up the gears which I have no idea how to do, or the tools to do it. HELP!!!!!!! At this point i obviously can't drive it to work tomorrow. Any chance someone who's done gears could come by and help me reassemble my Jeep tomorrow afternoon??? Please help.

 

[arctycfox]

wheel bearings look good, carrier bearings look good, but it has a chattering vibe.

 

[JJacobs]

Better tear the engine down, sounds like a loose kenuhtson reaction damper.

When you hit the brakes the rear pinion comes down, changing angles in the driveshaft and increasing the tcase output operating angle. So look in that area- check tcase fluid appearance for damage, check the ujoints. Another possibility is loose exhaust grounding out on decel.

Since you have it apart, are the pinion bearings turning smoothly, no slop?