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Replace rear differential gasket?


Freshman Member
My rear diff is leaking. Whats it take to replace? Trying to decide if I should take it to a shop instead of doing myself. cheers,

Deleted member 8987

Boy, rear diffs are very difficult to fix.
Front ones are real easy on these cars, however.
Too bad it's not the front one.

You sure it's the gasket and not the pinion seal?

Been a lotta years since I did one, but it's a drop out third member isn't it?

You have to pull the wheels, pull the axle shafts, drop the driveshaft, unbolt the thrid member, drop it out the front.

Usually it's the pinion seal, but if you think it's the gasket, that's what you have to do.
Country flag

Where exactly is it leaking? If it is at the pinion seal you can repair that without pulling the differential unit by picking the seal out from the front.

If it is leaking from around the flange of the differential unit perhaps you will only need to replace the paper gasket and torque down all the nuts evenly. Maybe it is just the drain plug?

Or is it leaking from somewhere out toward the hubs--a whole nother experience.

It is not hard to isolate and accurately locate the source of the leak. Come back to us with more information and we'll take it from there.


Jedi Knight
Country flag
I would be really happy if the only leak I had was the differential. Mine doesn't leak, but everything else does -- transmission, rear main, front seal, steering gear, etc.


Freshman Member
You guys got me thinking. I really didnt notice a leak until after I replaced the oil in the diff a few months ago. It could be the drain plug. I didnt have the correct tool for that square plug. So I improvised. Any idea where I can get that correct tool? cheers, Zane
Country flag
Sounds like you need a smoke wrench.


Country flag
Another option would be cutting a piece of 7/16" square bar and putting it in a 7/16" 8 point socket. This one is for a 1/2" ratchet.


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Deleted member 8987

If I recall, 'tis.

If you have the ability......find a piece of 7/16" square stock about, oh, 12-14" long.
Clamp about 1.5 to 2" in a vise, heat it cherry red with an oxy-acetylene torch, BEND the long part to 90 degrees, let it cool, de-burr the edges, and you now have a tool you can keep in your toolkit.
Country flag
You can also use a 19 mm 12 point socket to remove a 1/2" square fill plug--I just did it today when I changed my diff oil.
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