I recently rebuilt my rear differential and did not use a gasket to replace the cover. I just used a thin bead of Permatex Black Gasket maker/silicone. No problems with leaks.
Good morning Rust! Your rear differential looks like an Eaton HO52 to me. The rear cover gasket you need is a FELPRO RDS5088 Gasket . You can look them up online. Just search FELPRO RDS5088. This is the gasket I purchased and installed on my 1954 3604 which has the Eaton HO52 Rear differential. Here's a photo of mine...
Last edited by Dusty53; 09/13/202312:57 PM. Reason: added detail
Ron - - Dusty53 1954 Chevy 3604 In the Gallery Forum "You can't dance with the Devil and then wonder why you're still in Hell." "They will forget what you've said, and they will forget what you have done but they will never forget the way you made them feel."
Going to pick this up while I wait for the gasket. Going to have to change this oil a few times, looks like it hasn’t been changed in many many years. Going to flush out the old sludge.
You should be able to flush it out . I drained the rear diff oil by loosening up the rear cover bolts enough to allow it to drain, retightened the bolts, filled it up with diesel fuel, raised the rear end off the ground and let it operate in 1st gear for a few minutes , loosened the rear cover to drain the diesel, removed the rear cover, checked for any obvious issues, replaced the cover/gasket, refilled with 80-90 Gear Oil, and went on down the road.
Note that mine leaked at the front seal, so I went through the process of replacing the front seal while I was working on the rear diff......now that front retainer gasket may be a bit harder to find. PM me if you decide to go down that road and I'll share what the experts shared with me.
Best wishes on your project.
Last edited by Dusty53; 09/14/20233:53 AM.
Ron - - Dusty53 1954 Chevy 3604 In the Gallery Forum "You can't dance with the Devil and then wonder why you're still in Hell." "They will forget what you've said, and they will forget what you have done but they will never forget the way you made them feel."
I made all the gaskets for the rear axle, that includes the axle shaft hub covers, front pig, rear cover, and front pinion bearing retainer gaskets. I used a heavy FelPro material for the front and rear and a lighter McCord paper for the hub and pinion. A little Permatex #2 and all is well.
1957 Chevrolet 5700 LCF 283 SM420 2 speed rear, 1955 IH 300U T/A, 1978 Corvette 350 auto, 1978 Yamaha DT175, 1999 Harley Davidson Softail Fat Boy
Looks like a HO72 rear end, which would be correct for the 3800. I used Fel-pro RDS5090 carrier gasket and Fel-pro RDS5088 cover gasket when I went through the one on my '58.
