Sticking posi?
Thread Starter
Burning Brakes
Joined: Apr 2001
Posts: 904
Likes: 0
From: Langley, BC, Canada
Sticking posi?
So my rear end has been screwed up for a few months now. I ignored it since im not driving the car, but I have a serious offer for it and i'd like to get it fixed.
So heres the symptoms..its fine when cold. It can sit running for an hour and its fine. Once i start driving after about a 1/2 hour the rear end starts to clunk. It only does it while turning at slow speeds, or backing up. It sounds like someone is hammering on the diff, and the entire rear end shakes. At first I thought it was the new bearing i installed, since it started doing this about a week later. I reinstalled the old bearing since it was still ok, and the noise is as bad as ever.
So i did some reading tonight and come across people who have the same symptoms. It's usually caused by too much friction in the posi, and then when it suddenly releases it clunks.
It was recommened to flush the diff 2 or 3 times and then use synthetic with the posi additive. Followed by a bunch of figure 8's.
Drained the old oil tonight. It was more or less black sludge. Im going to buy some gear oil and posi additive tommorow.
Sound like a plan? Hopefully the clutches arent fried. Since its not slipping I can only assume they're still good.
Is there any special treatment i could throw in to keep it quiet for a while so i can unload it?
Btw ujoints are only a few months old and bearing have minor play in them. I get some clunk when shifting from park to gear, but its a completley different sound.
[Modified by nsimmons, 2:02 AM 11/29/2002]
So heres the symptoms..its fine when cold. It can sit running for an hour and its fine. Once i start driving after about a 1/2 hour the rear end starts to clunk. It only does it while turning at slow speeds, or backing up. It sounds like someone is hammering on the diff, and the entire rear end shakes. At first I thought it was the new bearing i installed, since it started doing this about a week later. I reinstalled the old bearing since it was still ok, and the noise is as bad as ever.
So i did some reading tonight and come across people who have the same symptoms. It's usually caused by too much friction in the posi, and then when it suddenly releases it clunks.
It was recommened to flush the diff 2 or 3 times and then use synthetic with the posi additive. Followed by a bunch of figure 8's.
Drained the old oil tonight. It was more or less black sludge. Im going to buy some gear oil and posi additive tommorow.
Sound like a plan? Hopefully the clutches arent fried. Since its not slipping I can only assume they're still good.
Is there any special treatment i could throw in to keep it quiet for a while so i can unload it?
Btw ujoints are only a few months old and bearing have minor play in them. I get some clunk when shifting from park to gear, but its a completley different sound.
[Modified by nsimmons, 2:02 AM 11/29/2002]
Safety Car
Joined: Dec 2000
Posts: 3,767
Likes: 5
From: Jacksonville Fl
Re: Sticking posi? (nsimmons)
sounds like it needs flushing. But, if you simply drain it and put in VP GL100 it will never make another noise. If you use regular brand synthetics like Mobil1 you will need to put in some limited slip friction modifier or the noise will still be there.
Thread Starter
Burning Brakes
Joined: Apr 2001
Posts: 904
Likes: 0
From: Langley, BC, Canada
Re: Sticking posi? (BBA)
Success! no more clunky rear..flushed the fluid, went down to the dealer and got some posi additive. Filled her up with the additive and some mobil one synthetic, did a bunch of figure 8's, took it for a 1 1/2 hour drive and it was smooth and quiet the entire way, did some more figure 8's. All seems well.
