Rear End leaking... oh fun!

[ChillPhatCat]

Just got the car inspected and they took me in there to look at the differential while it was on the lift... it's slowly leaking out of the back gasket and through the front seal. I probably don't have the time to take care of this myself, so I'm wondering what a reasonable labor and parts charge would be? I know the parts should be cheap, should I just buy the parts and take it to a speed shop or what? I'd love to have them upgrade the rear end at the same time, but I probably can't justify it. How much more labor would it take if I did somehow justify a rear end gear upgrade?

TIA

 

[wmburns]

Replacing the pinion seal means the drive shaft, flange, pinion bearing, and crush sleeve have to be removed. Establishing correct pinion pre-load is a labor intensive process.

While the seal is cheap. The process to install is a PIA.

If the work is done during a gear swap, the seal replacement is a "free-be".

A leak from the rear cover is easy to fix.

 

[johnnyt03gt]

I would just put some stop leek in drive it like that.
For few weeks to get all your parts together. Upgrade whole thing.

 

[ChillPhatCat]

So most of the things that you need to do when you do a gear upgrade are done when the pinion seal is replaced? In that case I would be right in thinking that I should just do the upgrade while they're in there... I know a decent speed shop out here, I'll have to feel it out with them and see what they say.

 

[johnnyt03gt]

well if you just ask for a seal that's all ur getting,
you have lots of options. first thing you need to figure out what are ur plans for the car?
nitrous-blower-big slicks. or mostly stock DD myself i like keeping all my future mod options
open, and wouldn't spend $150-250 on a 'bandage' repair but that's just my opinion,

for just a daily driver. i would just have em replace all the bearings/seals ring&pinion gears,
also new stock 28 spline Differential Carrier,

the way i look things when it comes to rear ends. it's like needing an organ transparent, do it right the first tie so they won't cut you open every 6 months,

 

[ChillPhatCat]

Currently it's my DD, and I am a fan of some mileage on the highway. And, down the road... maybe 5 years if I still have the car, I hope to drop a blower on top or turbo it. So, 3.73's are what I've got my eyes on.

 

[trinity_gt]

Replacing the pinion seal means the drive shaft, flange, pinion bearing, and crush sleeve have to be removed. Establishing correct pinion pre-load is a labor intensive process.

Correct me if I'm wrong but you can replace the seal without removing the pinion doing by something like this:

• Remove the driveshaft
• Using a pointer-type in-lbs torque wrench, measure the pinion bearing preload by rotating the drive flange nut. Record the reading.
• Remove the drive flange nut
• Mark the drive flange and pinion relationship with an indelible mark so they can be re-assembled in the same orientation
• Remove the drive flange
• Remove the old pinion seal and install the new one. Smear some oil on the seal as lube
• Lube the splines on the pinion and align the marks on the pinion and drive flange made above. Install the flange.
• Apply some red-Loctite to the nut threads and install the nut. Tighten the nut in stages, rotating the pinion periodically to allow the bearings to seat properly.
• As the pinion nut is tightened, measure the pre-load with the in-lbs torque wrench and continue to tighten until the pre-load measurement matches that seen above
• Re-install the driveshaft using threadlocker on the bolts.

If you don't disturb the bearings and crush sleeve and return the bearing pre-load to its original value, the rear should be okay. No?

As well, the drive flange should be checked for a wear groove at the seal contact point. If there's a groove there, it's time for a new flange.

 

[trombonedemon]

Correct me if I'm wrong but you can replace the seal without removing the pinion doing by something like this:

• Remove the driveshaft
• Using a pointer-type in-lbs torque wrench, measure the pinion bearing preload by rotating the drive flange nut. Record the reading.
• Remove the drive flange nut
• Mark the drive flange and pinion relationship with an indelible mark so they can be re-assembled in the same orientation
• Remove the drive flange
• Remove the old pinion seal and install the new one. Smear some oil on the seal as lube
• Lube the splines on the pinion and align the marks on the pinion and drive flange made above. Install the flange.
• Apply some red-Loctite to the nut threads and install the nut. Tighten the nut in stages, rotating the pinion periodically to allow the bearings to seat properly.
• As the pinion nut is tightened, measure the pre-load with the in-lbs torque wrench and continue to tighten until the pre-load measurement matches that seen above
• Re-install the driveshaft using threadlocker on the bolts.

If you don't disturb the bearings and crush sleeve and return the bearing pre-load to its original value, the rear should be okay. No?

As well, the drive flange should be checked for a wear groove at the seal contact point. If there's a groove there, it's time for a new flange.

No, you're right. I had the dealership replace my pinion seal, just for good measure, only took them a couple of hours instead of 6 to 8 w/gutting the pumpkin.
O.p. If I were you, in my honest opinion, instead of going through the hastle of getting all of the materials together for a complete install of 4:10's, I would just find a really thick set of lower control arms. When you change the rear end gear ratio, you might as well replace the bearing and seals on the axles, new bearings in the gear housing, crush sleave, shims, gear oil w/modifier. Some things I left out. The job is long if you don't have a press, if you get the depth wrong the first time you gonna have to keep the pressing the bearing on and off.
Stock gears are not bad at all, if you get the majority of the torque and horsepower to the ground, then it might feel like you have 4:10's.

 

[ChillPhatCat]

Well it's not leaking anymore. Brought it to a speedshop up here and had them install 4.10's, and rebuild the carrier. For the longest time I swore up and down I'd only go with 3.73's, but people seemed to love 4.10's so much I decided to go for it. No more sounds, no more leaks and it burns rubber like hell now.

 

[hotdog71]

Well it's not leaking anymore. Brought it to a speedshop up here and had them install 4.10's, and rebuild the carrier. For the longest time I swore up and down I'd only go with 3.73's, but people seemed to love 4.10's so much I decided to go for it. No more sounds, no more leaks and it burns rubber like hell now.

Welcome to the 4,10 gang

One note be careful in the wet til you get used to 'em.