hensley73

how do you replace the rear seals in a 1980 corvette? i already have the rear end out.I hope someone can help.

Gordonm

You have to remove the axle stubs for the side yokes. Remove the back cover and then the cross pin. Slide the pin out and the axle stubs push them in to expose the snap rings. Remove the snap rings wit ha st of 90 degree snap ring pliers and if the stubs are not to worn they slide out. This exposes the seal.

The pinion seal you have to remove the front yoke. Mark where the nut is and remove it. The yoke will slide off. Tap the seal out then replace with a new one. The seal does not bottom out. Replace the yoke and put the nut back to exactly where it was. New gasket on the rear and you should be leak free.

hensley73

It's good to have someone to reply to these questions, I'm working in the dark. Thanks very much for your help.

jbakyy

So you can replace the seals without removing the rear end housing?

0Willcox Corvette

No, you must remove the cover to get to the snap rings in the rear end..

And just remember this is a Dana and there is not a crush sleeve in it. There are pre-load shims on the bearings but un-like the 1963-1979 style you don't have to be as careful with the front pinion nut.

The other issue you may have is the rear cover bolts. Make darn sure the threads for the rear cover bolts are good, clean and ready to roll before you go back together. They have a tendency to strip out.

Willcox

jbakyy

Thank you, so you just need to remove the cover and not the entire gearbox?

jbakyy

Oops, forgot a question. What if you are just replacing the front seal that connects to driveshaft?

0Willcox Corvette

If you are just doing a pinion seal then you don't need to remove the rear end from the car. Just follow the instructions laid out above by Gordon. Just count the number of turns when you remove it and you'll be fine.

Willcox

tracdogg2

Not on an '80. It's a Dana diff. No crush sleeve and the flange is a slip fit. Preload is set with shims, just torque the nut back on. No need to mark anything. The seal does not have a flange on it and must be fully bottomed in the bore to prevent leaking. There is a shim between the pinion flange and front bearing that will fall out when you remove the seal. This is not any easy job. Much harder than an iron diff. It will probably take you less time to pull the diff and replace the seals on the bench.
Mike

qwank

its really hard to get to the front seal while its in the vehicle, because the front mount protrudes outward and limits access.

RonR80

I took the diff right out , only 1hr job it's much easier to do on the bench , the whole diff only weights about 50 lbs.

0Willcox Corvette

Mike, I'm with you on the Dana. It was easier to say count the turns to get it back to the same torque. I actually forgot what the torque was on the front pinion nut.

It is hard to get that front pinion seal out on the car, but it is do-able.

But I'll ad to this a bit more.

Anyone ever have an issue with the threads in the case going back together? We pulled one of these two months ago and all the threads were shot in the alum. housing? Since 80-82 rears are not something we do all that often I'm wondering if anyone else has had this problem.

I talked to Pat Ikerd about this and he lead me to believe that in most cases you'll find the threads shot.

Willcox

hockey30

I have the same problem on my 1980 vett ---- a leaking pinion seal.... decided to pull rear end and replace all seals and bushing in rear end area. Also while everything was out do some clean up and painting. Thanks for all the tips.

Ravoll

I know this is an old thread,but I need to do the same.Was putting new exhaust on today and saw where it's slobbering everywhere.
I bought a complete kit with all new everything, less ring and pinion about a year ago.Actually I also bought everything for the whole rear suspension,and trailing arms,but been avoiding tearing it down cause I have no info on rebuilding this dana unit.
It can no longer be avoided.
I need some info on setting diff back up during reassembly.Pre loads,lash,pinion depth,torque specs,ect.

And a large portion of moral support.

Ravoll

No one ? Oh well,looks like I'm winging it.Thanks anyway