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Discussion Starter · #1 ·
When I pulled my gas tank to fix the leak I found that PO or his mechanic used the wrong size o-ring for the fuel sending unit gasket. There was a 2 1/2 inch (inner diameter) one in there and it was a tad too big (I used a 2 3/8 inch one in there as a replacement). The old o-ring was crushed a bit because it was too large which caused the leak. The puzzling aspect is that I've owned the car for almost two years and it just started leaking out of the blue a few days ago.

In my hunt for the proper o-ring I did manage to find some rope caulk at the local mom & pop hardware store. There was nothing between the tank and the trunk when I took it out. Way to go PO!

Thanks to everyone who responded to my posts.

Everything is fine now but I did notice that I have a pinion seal leak. I checked the old posts for the fix there and it looks like it would be difficult if not impossible to fix with the rear still in the car. It's not severe yet and considering I have the 2.80 gears I was thinking it would be easier and cheaper to pick up a cheap/free rear and swap it with mine.

I have to keep the car on the street and it needs to be moved for street cleaning so I can't leave it sitting all torn apart for long and if I take it to a mechanic it will be costly.

If the replacement has problems I can always work on mine and swap them back but in the meantime I can move the car back and forth across the street as needed.

10,588 Posts
Pinion seal replacement requires a crush sleeve, pinion housing o-ring and new seal...I'll use a new nut on gear setups but I don't feel it's necessary on this job.

Remove driveshaft. Break pinion nut loose (set parking brake to hold wheels)...nut is tight Sometimes a holding bar, slotted to barely clear the yoke flange is required to hold the yoke while breaking the nut loose (Quick and dirty method is 1" impact *G*)

Drain gear oil (removing pinion housing will do it)....mark pinion housing and carrier where they meet if housing doesn't obviously have an "up" side; remove pinion metal shim

Clamp pinion yoke in bench vise (You'll need a sturdy one) and remove nut; remove yoke; remove pinion through bearings (bonking may be required; use nut to protect threads until loose), then remove pinion seal, front bearing and crush sleeve. Remove front seal. Examine yoke seal area for wear and repair or replace as necessary.

Install front bearing and pinion seal. Lube pinion seal. Slide new crush sleeve over pinion shaft and insert from back side. Install yoke and use it as a rest point to bonk or press pinion shaft through bearing. Do not eliminate bearing play (that will be done with torque wrench on pinion nut) Install new o-ring on outside. . Install and tighten nut by hand (nut can be used to pull pinion shaft through bearing but I don't like to). Clamp yoke in vise. Follow service manual procedure to set bearing preload by torquing pinion not over tighten; if you do, the crush sleeve is junk and will have to be replaced.

Once bearing preload is acceptable (IME, with used bearings, if the housing spins easily but there isn't any noticeable play, it's good to go), re-install pinion housing assembly into rear end, lubing o-ring and re-installing metal shim. Torque retainer bolts to spec. Rotate pinion through a couple times to check for any problems (tires still off ground, parking brake released).

Re-install driveshaft (check u-joints for wear)....Fill with oil; Road test...

In the shop, such a job would take about 60-75 minutes if everything co-operated.....maybe another 15 or so if I had to use the press to get the pinion out or the yoke off...

If you have a shop do it, it should run under 100.00 + parts, depending on the local labor rate.

Have fun!

PS,...this is all likely in your service manual so you can correct me where I've gone astray..*G* It's late!

Discussion Starter · #3 ·

All I can say is "Wow". When I did the search for the procedure I found good information by you and Art. Somehow you've managed to supplement the wealth of knowledge that was hiding in the depths of the VMF.

It's posts like this that makes me saddened by the loss of the old forum. Someone reading this definitely won't have to ask about pinion seal replacement so you won't have to go over it again and again.

Maybe you should start archiving some of your posts (like this one) just in case this incarnation of the VMF goes belly-up also.

Anyway, the problem with bringing it to a shop is that they look in their little rate book for the times and charge you based on that even if the amount of time spent doing the repair is much shorter. I can easily see being charged 4 hours labor on this and at $65 per hour plus parts and tax I'll be out over $300.

It just seems to me that you can't get your car out of a shop nowadays without spending at least $300. The "do it yourself" factor did weigh in somewhat when I was determining which model car to buy. I think I made the right choice.
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