rear end noise

[twanita]

i have new 3.53 posi and have not put in tubes of posi-lube yet. i get a lot of noise back there when going straight even in neutral. it sounds like the noise from a mechanical throwout bearing scraping a clutch diaphram except it seems to be coming from the rear. is that what noisy posi clutches sound like or is my throwout bearing just echoing back there? jim o.

[souzape]

Jim- is there some reason why you haven't put the posi-lube in yet??

Phil Souza

[K.Wilson]

Jim,
I believe the noise you are hearing is probably the disc brake pads on the rotors or the parking brake pads on the rorors if you have the Jag parking brakes. Does the sound go away when you to gently apply the brakes?
Keith

[peter]

I have the same noise-- little squeaking-- apply the brakes and it gets louder, apply brakes harder and it goes away. I adjusted my front/ rear brake bias and the noise is less than before. I have 3300 miles. I hope its a dragging brake pad and it eventually wears away. Your thoughts.....

[twanita]

no, it is not a brake noise although my brakes are still not right.
souzape,the only reason i have not added it is i was curious to see how rear end acted without it then with it. i guess i should just add it anyway.
i am going to adjust clutch rod shorter and put a heavy spring on the fork to make sure i have a gap between throwout bearing and diaphram. maybe the sound is just echoing to the rear.

[chris knueven]

jim,

take it from a guy who forgot to put friction modifier in his diff......
you will break the posi eventually,then it gets expensive real fast.....

chris

[peter]

i bought my car built. how can i tell if the friction modifier is in there?

[twanita]

i'll put it in tonite. 2 tubes or 1?

[chris knueven]

peter,

the car will make a pretty noticeable groaning when making a real tight
turn at low (idle) speed.

jim,

i seem to remember the bottle that came with my auburn unit was around
8 oz. most people recommend 1 bottle of the ford friction additive
for most all diffs.....

chris

[JeepSnake]

Peter - if your brake pads are semi-metallic in the rear, you may just be experiencing squeal/squeak/groan/grating noise from corrosion.

I get the same noise in the rear after washing the underside of the car and then letting it sit for a couple of days. After using the brakes a couple of good times, I've knocked the surface/flash corrosion off the pads & the rotors, and all is well.

Same thing happens on our daily driver Jeep Cherokees (and on a couple of friends' Dodge Dakotas with the same rearend), particularly on cold, foggy, drizzly winter days. After the first couple of traffic lights, away it goes.

I've seen an extreme case where the drums seized to the shoes due to corrosion on both (car had been sitting several weeks).

[peter]

Im assuming its the brakes too. The noise changes based on how hard I press the brakes -- and its slowly going away the more miles i put on.

Ill check for the differential sound in the morning-- thanks for the tip-- so if I hear the groaning-- I need the additive? peter

[will butterworth]

park ave. squeals-scrapes, groans and other things even on a rainy day when i first apply brakes, semi-metallic. Mayby that is all it is, hope so.Will-alabama