Grinding/sliging noise

RatLabGuy

RatLabGuy

You look like a monkey and smell like one too
Joined
May 18, 2005
Location
Churchville, MD
'89 4Runner, auto tranny.

I'm getting this odd noise that sounds like something is grinding or sliding that should not be doing so... sounds like coming from either rear axle or back end of tranny. Hard to tell which from the driver's seat...
Only occurs when travelling > ~50 mph, and just at the moment when the engine is engaging/disengaging throttle. In other words, not when foot on gas, or not on gas - just very briefly as when it lets all the way off, or first engaging. If I'm really delicate I can feather/"ride" the pedal just a heair and make it stay for a few seconds.
Gets louder w/ speed, very noticible at 65-70 etc (and let off gas). Who knows maybe the problem occurs at slower speeds but is inaudble.

I am perplexed. No wiggle in driveshaft, everything is lubed.
It appeared about 2 days after I lifted the back end (from droopy stock) ~3" though. However no shaking/obvious driveline issues.
 
Not when I'm coasting, though. Only at the moment when the gas is *being* applied or released; once released, no problems.
 
could be bad T-case output bearing or Pinion bearings. I get a clunk in my ZJ at the same time as you get your noise. Right at that floating point between power and no power. When you checked for slop in the driveshaft, did you have the back tires off the ground? If not, get the rear ona jack or better yet, jack stands, and then check for slop again.
 
Yo,
Start with the easy and cheap stuff first....driveshaft. A greater angle
induced on the joints that have been happy at less angles are likely now complaining. Probably not axle or trans since those bearings are less affected by changes in driveshaft angles UNLESS pinion bearing is on its way out. If so, seal should be leaking.

:beer:
 
Back
Top