Rear end help please !!

[BoostedTtype]

My 87 turbo regal is having rear end issues. I can drive around for a while (maybe a hour or so) and then the rear will start to make noise and kinda grind. It seems like this only happens when the rear is hot I guess. Its really bad when I turn sharp either way while driving. After the car sits for a while it will act as if it never happened and the rear will work great noise and grind free. Posi still works great too.

Suggestions please help.

 

[jhanson1750]

Do you have the correct additive in the lube? I have had all kinds of problems using oil that "already has that stuff" so now I always add friction modifier. It could be a bearing going as well. Hard to tell. I would check it out by opening it up and see what is going on. Jon Hanson

 

[BoostedTtype]

Whats the best fluid and additive for the rear end?

Thanks

 

[craggar]

I would pull the cover off and have a look but it sounds like you don't have the addative like Jon mentioned. GM sells it and it's called posi addative or something like that.

 

[mikestertwo]

Whats the best fluid and additive for the rear end?

Thanks

Get the oil and additive from GM.

 

[83ttypecooled]

Hi,
Royal Purple is good stuff,and contains the castor oil limited slip differentials like.It costs a bunch, but lasts a long time. If your diff problems persist, I would start thinking of a rebuild.

 

[superjaay]

I have to change my rear diff fluid once a year or it starts to grind. Make sure you use the GM stuff and the additive. I cost a lot but it always make the grinding sound go away.

 

[BoostedTtype]

Okay sounds good. Thanks too all for your help. I will make a trip to the dealer Tomorrow to pick up the fluids. Any idea on how many I will need of each?

Thanks

 

[mikestertwo]

If memory serves me right 3 bottles of the lube and 1 bottle of the additive.

 

[gczarny]

My 87 turbo regal is having rear end issues. I can drive around for a while (maybe a hour or so) and then the rear will start to make noise and kinda grind. It seems like this only happens when the rear is hot I guess. Its really bad when I turn sharp either way while driving. After the car sits for a while it will act as if it never happened and the rear will work great noise and grind free. Posi still works great too.

Suggestions please help.

if you have NOT change your rear end fluid for a while get synthetic fluid and additive and if you did ...just add limited slip additive , that should help !

 

[BoostedTtype]

I recently drained and inspected my rear and put new fluid and posi additive in it and it has worked great ever since. You guys are Awesome!!!

Thanks

Heres a pic

 

[Blown&Injected]

What seems bad is that you said it happens after a long ride/warm up and when turning. Mine has just started doing this and some research suggests bearings.

I ran my low on oil and do not believe I will be so lucky to just do a oil change

 

[turbo nasty]

Valvoline dino 75w90, i bottle of dino Lucas oil stabilizer and i tube/bottle of the limited slip additive.

 

[mikestertwo]

Looking at your picture of the rear it looks like it's due for a clutch replacement. Notice the gap between the two center stationary plates in your clutch pack on the right side. Getting kind of thin.

 

[BoostedTtype]

I noticed that too. What else should be changed when changing the clutches out?

 

[mikestertwo]

Just make sure when you change the clutch packs you get the selective washers back in the same side. They are stamped with a number denoting thickness.

 

[driveshaft man]

If you continue to have slip-stick problem,use Ford friction modifier.It has solved slip-stick for me that 2 bottles of GM additive and fresh Valvoline high performance gear oil would not stop.Eaton recommended it on a warantee issue.I would definitely use it on a fresh rebuild.