Where is this differential leaking? (pics)
Thread Starter
Racer
Joined: Jun 2004
Posts: 384
Likes: 0
From: freehold NJ
Where is this differential leaking? (pics)
On my 1974 onvertible vette:
I started out just wanting to replace the bolts/bushings on my rear leaf spring. But not what it's off (used map gas to heat up those bolts and that worked well). Well, now the diff is leaking about 2-3 drops/day wether it sits or gets driven.
Does it look like it's leaking from the side shafts in addition to the rear seal? If so, I know I'll have to drop the thing which I'm scared of because I know you have to mark where the half shafts were or something.
But if I could just replace the rear seal, can't you get to those bolts on top of the rear crossmember with a wratchet wrench and short extention?
Here I have the spring almost off
I started out just wanting to replace the bolts/bushings on my rear leaf spring. But not what it's off (used map gas to heat up those bolts and that worked well). Well, now the diff is leaking about 2-3 drops/day wether it sits or gets driven.
Does it look like it's leaking from the side shafts in addition to the rear seal? If so, I know I'll have to drop the thing which I'm scared of because I know you have to mark where the half shafts were or something.
But if I could just replace the rear seal, can't you get to those bolts on top of the rear crossmember with a wratchet wrench and short extention?
Here I have the spring almost off
Instructor
Joined: May 2006
Posts: 203
Likes: 1
From: El Cajon CA
It looks like halfshaft seal on one side and maybe pinion seal too. Are you able to remove the rear differential? I'd pull it, remove the cover, drain the fluid, chedck the insides, and at least put new yoke and pinion seals in along with new lube/posi additive.
Melting Slicks
Joined: Jan 2004
Posts: 2,672
Likes: 1
From: New Cumberland PA
It's been a year or two since I dropped the rear. I would do it the normal way; pop off the rear cross member. There are different ways to do it. I loosened up the two cross member bolts and used a long screwdriver. No F'ing way. I then bought a 36" crow bar. It was over kill. The crossmember popped of without much effort. By loosening the bolts, I do it by taking them out and then turning them back in 3 or 4 threads; possibly more depending on how much tread is there. That way you can 'break' it free without it falling down. Someone, who I won't mention, tool a dremel and cut the fiberglass above the bolts to get access to them to drop the rear. His car is used for racing and he doesn't care about extra holes.
Dropping the rear is not that big of a deal. The thing is quite heavy and I would recommend lowering it with a floor jack. Trying to find some sort of short cut usally means it take longer. Speaking from experience, you normally bust your azz trying to work around the correct way and then wind up doing it the correct way in the end.
How did you make out with getting the car to sit a little lower?
Dropping the rear is not that big of a deal. The thing is quite heavy and I would recommend lowering it with a floor jack. Trying to find some sort of short cut usally means it take longer. Speaking from experience, you normally bust your azz trying to work around the correct way and then wind up doing it the correct way in the end.
How did you make out with getting the car to sit a little lower?
Thread Starter
Racer
Joined: Jun 2004
Posts: 384
Likes: 0
From: freehold NJ
Originally Posted by mandm1200
It's been a year or two since I dropped the rear. I would do it the normal way; pop off the rear cross member. There are different ways to do it. I loosened up the two cross member bolts and used a long screwdriver. No F'ing way. I then bought a 36" crow bar. It was over kill. The crossmember popped of without much effort. By loosening the bolts, I do it by taking them out and then turning them back in 3 or 4 threads; possibly more depending on how much tread is there. That way you can 'break' it free without it falling down. Someone, who I won't mention, tool a dremel and cut the fiberglass above the bolts to get access to them to drop the rear. His car is used for racing and he doesn't care about extra holes.
Dropping the rear is not that big of a deal. The thing is quite heavy and I would recommend lowering it with a floor jack. Trying to find some sort of short cut usally means it take longer. Speaking from experience, you normally bust your azz trying to work around the correct way and then wind up doing it the correct way in the end.
How did you make out with getting the car to sit a little lower?
Dropping the rear is not that big of a deal. The thing is quite heavy and I would recommend lowering it with a floor jack. Trying to find some sort of short cut usally means it take longer. Speaking from experience, you normally bust your azz trying to work around the correct way and then wind up doing it the correct way in the end.
How did you make out with getting the car to sit a little lower?
Drifting
Joined: Aug 2005
Posts: 1,430
Likes: 8
From: Hamilton NJ
Looks like most/all of the leak is from the yoke seals that is getting blown back to appear like a cover leak. Good luck with the removal.
You may strongly consider replacing the yokes themselves if they are original. The dust covers on the yokes are sitting so close to the diffential case it likely means the yoke ends inside the differential have worn and are mushrooming. I expect you have exceeded the camber adjustment range on your strut rod mount?
You may strongly consider replacing the yokes themselves if they are original. The dust covers on the yokes are sitting so close to the diffential case it likely means the yoke ends inside the differential have worn and are mushrooming. I expect you have exceeded the camber adjustment range on your strut rod mount?
Tech Contributor
Joined: Aug 1999
Posts: 15,176
Likes: 3,994
From: Connecticut, USA
Differential leaks are usually from :
1- Pinion seal/yoke splines
2- side yokes wearing down and grinding the seal be careful if this goes too long you'll lose the differential
3- cracked rear cover from too long spring bolts. Look like you have oil in the spring pad area so I would look for a crack or long bolts.
Replacing the yoke alone will not get the endplay under .010 in most cases, you'll need to replace the clutches and tune them. This will end being an overhaul if you go that far.
1- Pinion seal/yoke splines
2- side yokes wearing down and grinding the seal be careful if this goes too long you'll lose the differential
3- cracked rear cover from too long spring bolts. Look like you have oil in the spring pad area so I would look for a crack or long bolts.
Replacing the yoke alone will not get the endplay under .010 in most cases, you'll need to replace the clutches and tune them. This will end being an overhaul if you go that far.
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Drifting
Joined: Aug 2005
Posts: 1,430
Likes: 8
From: Hamilton NJ
Originally Posted by 90ZR1
OK, so who in central NJ can fix this thinkg?
Drifting
Joined: Jan 2004
Posts: 1,991
Likes: 3
From: Piscataway NJ
1.Did it leak before you started ?
2.When heating up the bolts to remove them you may have cooked the diff. gasket at the least. And maybe the side yoke seals.
The posi tag on the fill plug looks a little wilted. So I think you may want to clean every thing up and go from there. Jack
2.When heating up the bolts to remove them you may have cooked the diff. gasket at the least. And maybe the side yoke seals.
The posi tag on the fill plug looks a little wilted. So I think you may want to clean every thing up and go from there. Jack
Thread Starter
Racer
Joined: Jun 2004
Posts: 384
Likes: 0
From: freehold NJ
Originally Posted by Artsvette73
1.Did it leak before you started ?
2.When heating up the bolts to remove them you may have cooked the diff. gasket at the least. And maybe the side yoke seals.
The posi tag on the fill plug looks a little wilted. So I think you may want to clean every thing up and go from there. Jack
2.When heating up the bolts to remove them you may have cooked the diff. gasket at the least. And maybe the side yoke seals.
The posi tag on the fill plug looks a little wilted. So I think you may want to clean every thing up and go from there. Jack
