my rear end is making a whinning noise

[rawlinss 14]

Fresh Build. My rear end is making a whinning noise when I let off the gas.

3.55 Gears, Posi Traction 8". Just had it rebuilt. Sent the guy who built it an email, but haven't heard back from him yet. Is this normal for a new rear end? Don't want to damage anything....

Sandie

[68stang289 26]

At what speed(s) does the whine occur? Does it make any grinding sounds? Have you confirmed there is the proper fluid in it? Is your car a manual? If so, does it whine when you have let off the gas and pushed in the clutch? It could be the back lash on the ring and pinion gear was set wrong. I have heard (though never experienced) that even a slight misalignment of the ring and pinion gears can cause it to whine.

 

In any case, I wouldn't drive the car until you can get to the bottom of it. If it is a misalignment, you can cause irregular wear to the ring and gear which could require complete replacement if the wear pattern is bad enough.

[rawlinss 14]

-whinning @ .....only have had the car up to 50's.

 

-car is automatic

Edited January 16, 2013 by rawlinss

[68stang289 26]

-whinning @ .....only have had the car up to 50's.

 

-car is automatic

 

So it whines at any speed once you take your foot off of the gas? Did the builder tell you to add any kind of friction modifier to the rear diff when you added the fluid to it? I only ask because my 06 GT had rear end whine and Ford's "solution" was to add in some friction modifier. I was told some rear ends require it to work properly (there's a joke somewhere in that statement).

[rawlinss 14]

yes, whines at any speed once you take your foot off the gas. Added Posi Traction additive before putting in 85/140 Valvoline Differential Oil. Bought some Lucas High Performace Rear Differential Oil tonight. Will try it out tomorrow....

[Boogerschnot 12]

Sounds like you need to pull it and have it re-checked. What brand gears did you use? Some gears are made better than othes. If it was set up properly using the reccomendation of the gear manufactor, it shouldnt make noise. Pull the chunk and take a look.. i know it sucks but if he didnt set up properly you could ruin the gears, bearings, seals, everything.. ask me how i know.. lol

[Mike65 475]

I had the same problem with the rear in my old 68 GT Coupe when I installed 3.50 gears in the 9" rear. I was told by a Ford tech that the pinion preload was not set right.

[Wycked69 20]

Fresh Build. My rear end is making a whinning noise when I let off the gas.

3.55 Gears, Posi Traction 8". Just had it rebuilt. Sent the guy who built it an email, but haven't heard back from him yet. Is this normal for a new rear end? Don't want to damage anything....

Sandie

 

First let me say you could have put a little more thought into how you worded the title of this thread......... God sakes, I've had 10 different "1- liners" I've kept to myself see the thread title. However, since you are a lady I am minding my manners.

 

You wont know whats causing the noise in your rear end till you pull the pig and check the wear pattern. My guess the pinion depth is its not set correctly or the pinion does not match the ring gear. Could also be they went to far with the pinion nut.

[redmach69 10]

From the rear ends I have built, I would say the preload or the backlash is off.