Grinding Noise From Differential
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Pro
Joined: Feb 2005
Posts: 627
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From: Frisco TX
Grinding Noise From Differential
When I turn sharp at low speeds my differential makes a grinding sound. Am going to change out the fluid. Have a 74 SB auto with a stock rear end. Here's my questions:
1) What type of fluid do I use and how much?
2) I've heard something about an additive. What is this and how much do I use?
3) Is there a drain plug? If not do I need a special tool to extract the fluid?
Thanks
1) What type of fluid do I use and how much?
2) I've heard something about an additive. What is this and how much do I use?
3) Is there a drain plug? If not do I need a special tool to extract the fluid?
Thanks
Drifting
Joined: Nov 2003
Posts: 1,634
Likes: 4
From: Northern NJ
St. Jude Donor '04 & '05
Originally Posted by jcoulter
When I turn sharp at low speeds my differential makes a grinding sound. Am going to change out the fluid. Have a 74 SB auto with a stock rear end. Here's my questions:
1) What type of fluid do I use and how much?
2) I've heard something about an additive. What is this and how much do I use?
3) Is there a drain plug? If not do I need a special tool to extract the fluid?
Thanks
1) What type of fluid do I use and how much?
2) I've heard something about an additive. What is this and how much do I use?
3) Is there a drain plug? If not do I need a special tool to extract the fluid?
Thanks
1) Some will recommend the GM fluid but I have found that any quality 90W dino gear oil will work OK. Get two quarts.
2) You should use the GM posi additive which comes in 4 oz bottles. Get two of these.
3) No drain plug unless someone previously added one. You will need some kind of a suction pump to pull out the fluid from the fill hole.
Remove the current oil, add about half a quart of the new oil. Then mix the two bottles of posi additive into the other 1/2 quart and add this to the diff. Finally top off until the fluid just starts to run out the fill hole with the second quart of gear oil. Then go out to a parking lot and do a series of either tight left and then right turns or figure eights to work the new oil/additive into the posi clutches.
This "should" make a hugh difference in the operation of the diff and quite things down alot. It did on mine.
Good Luck!
Last edited by ACECO; Oct 3, 2005 at 09:54 AM.
