Drain hole on the rear diff...
Thread Starter
Instructor
Joined: Jul 2005
Posts: 232
Likes: 0
From: Charlotte NC
Drain hole on the rear diff...
I just purchased a 91 coupe, and am in the process of changing ALL fluids (as recommended here).
Anyway, I removed a screw that is on the rear of the rear diff, but nothing came out??
The screw does not face the bottom of the unit, it faces the rear of the car, so if you laid down...the screw head would be facing you.
I assumed this was a drain plug, but after further research, I discovered that the rear diff has no drain plug.
I removed the fluid via the fill hole and put new fluid in.
Anyone know what the screw I have is for?
Anyway, I removed a screw that is on the rear of the rear diff, but nothing came out??
The screw does not face the bottom of the unit, it faces the rear of the car, so if you laid down...the screw head would be facing you.
I assumed this was a drain plug, but after further research, I discovered that the rear diff has no drain plug.
I removed the fluid via the fill hole and put new fluid in.
Anyone know what the screw I have is for?
Melting Slicks
Joined: Apr 2001
Posts: 2,877
Likes: 7
I believe you are talking about one of the bolts that holds the batwing to the pumpkin. Not something you want to remove if that is what it is.
Take a look at my sig - my diff is painted black but is what you removed on the bottom facing the back of the car? Is so it should be put back.
Take a look at my sig - my diff is painted black but is what you removed on the bottom facing the back of the car? Is so it should be put back.
Race Director
Joined: Feb 2003
Posts: 11,671
Likes: 20
From: Lake Wylie SC
I just pumped out my dif yesterday and I think I got more on me than in the dif. There is a procedure to install a drain plug in our differentials, but I keep on loosing it. There is a kit you can buy from one of the catalogs that gives you a special drill with a stop and a template to locate the hole. I'm thinking I'll do this the next time I change out the lub. Oh, don't forget the limited slip additive. I used 1 1/2 bottles, I spilled the rest.
Le Mans Master
Joined: Mar 2004
Posts: 8,700
Likes: 298
From: Ft. Lauderdale Fl
Go to www.c4guru.com then click "tech library" then click "drive train". Bogus has a step by step with pictures on how to change the diff lube.
Race Director
Joined: Feb 2003
Posts: 11,671
Likes: 20
From: Lake Wylie SC
Go to www.c4guru.com then click "tech library" then click "drive train". Bogus has a step by step with pictures on how to change the diff lube.
Thread Starter
Instructor
Joined: Jul 2005
Posts: 232
Likes: 0
From: Charlotte NC
Using this procedure I could only get 1 qt and maybe 5 oz out with that pump. Any body know the capacity of the diff? I couldn't find it in the Helms Manual. The GM rear axle lub came in 23 oz bottles. I only got about 40 oz in before it started coming out the plug hole. Oh, plus the 1 1/2 bottles of additive.
A book I have states 2 Qts, but I had about 1/4 of a quart left...but I
got in 2 bottles of additive.
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From: Mexico Beach FL
