Leaking rear differential

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Lucas
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Leaking rear differential

Post by Lucas »

My f150 appears to be leaking out the back seal of the rear differential. I have no idea if this should be an easy seal and fix or if Ill need a new axle. Any ideas? Ill post a picture later today.
'94 Ford F-150 302
'96 Ford Explorer Sport
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jstables
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Re: Leaking rear differential

Post by jstables »

Should be an easy fix to just pull the cover, clean everything well where the seal is gonna go, rtv it and fill it up with fresh fluid.
John

DD-05 F150/Lariat 4dr/5.4/dual exhaust
Beater-Free 1988 XJ/~4"s10 leaf & 4.5"coils/long arms/35s
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BadAssEddie
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Re: Leaking rear differential

Post by BadAssEddie »

It's easy peasy to fix. I used to have to do it after every wheeling trip in my Bronco Freshman year.

Take the cover off and drain the fluid

Clean the old gasket material and/or RTV off the two mating surfaces (diff cover and axle housing)

Reapply RTV on the axle housing, making a continuous bead going inside of the bolt holes.

Put the cover back on

Tighten the bolts in an alternating pattern

Wait 30 minutes for the RTV to set up

Refill the diff

This should fix your issue, make sure the cover mating surface is flat and that all the threads are clean and good on the bolts and in the axle housing.

Consider buying an aftermarket diff cover for the 8.8 like this one: http://eastcoastgearsupply.com/i-520897 ... cover.html

I got really fed up with my flimsy stamped steel one. It will pay for itself. Diff fluid, RTV, and gaskets get expensive. You make it leak everytime you go out, I promise. Plus it's inconvenient and wasteful to leak gear oil.
1969 Cadillac Deville 7.7 Big Block
1978 Ford F-150 6.4 FE
1993 Ford Bronco 5.8 Windsor
1994 Ford F-250 7.3 Powerstroke
2016 Ford F-250 6.7 Powerstroke
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Mr.WJ
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Re: Leaking rear differential

Post by Mr.WJ »

I've also heard great things about using "Lube Lockers" instead of RTV. A little more costly, however easier and reuseable.

http://lubelocker.com/products/lub-llr-f880
- 04 WJ Overland 4.7 HO, Bilstein 4600s, Tuned, 242HD Swap, 31" A/T's for cool kids
- 04 WJ Laredo 4.0, 3" OME HD Lift, Bilstein 5100s, JKS TB, IRO LCA's UCA's
- 05 LJ Rubicon 4.0, 3" OME HD Lift, Bilstein 5100's, JKS TB, Bumpers, Warn 9500ix, on 33 MTRs :cool:
- Bronco Water Pump Specialist, now leaks, fixed again and leaks for the second time
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TerryD
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Re: Leaking rear differential

Post by TerryD »

I use the factory style paper gaskets with indian head gasket shellac. I don't always trust RTV to seal properly and you could very easily get too much and a piece of that in a wheel bearing or pinion bearing is bad news. Cleaning the surfaces with brake parts cleaner to get the oil and trash off them will also help make a good seal.
Terry
Offroading: The hobby of turning perfectly good vehicles into scrap metal. :cool:
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Lucas
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Re: Leaking rear differential

Post by Lucas »

I'm going to degrease it for now and find exactly where the leak is but if it is just the seal I'm going to need a place to work on fixing it.
'94 Ford F-150 302
'96 Ford Explorer Sport
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TerryD
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Re: Leaking rear differential

Post by TerryD »

Lucas wrote:I'm going to degrease it for now and find exactly where the leak is but if it is just the seal I'm going to need a place to work on fixing it.
You have no parking lots where you live? :lol2:
Terry
Offroading: The hobby of turning perfectly good vehicles into scrap metal. :cool:
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Collison
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Re: Leaking rear differential

Post by Collison »

I use lube lockers.
They are more expensive to buy than a tube of rtv but are reuseable and when I need to service it I don't have to scrape off old rtv and when refilling you don't have to wait for it to dry before refilling.

Its real easy to do, easily done in a driveway or back yard.

I would recommend a torque wrench when reinstalling.
Collison - 2005 Jeep Rubicon
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BadAssEddie
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Re: Leaking rear differential

Post by BadAssEddie »

Lucas wrote:I'm going to degrease it for now and find exactly where the leak is but if it is just the seal I'm going to need a place to work on fixing it.
This, along with most repairs, is a parking lot job.

General, consensus:

Buy an offroad service aftermarket diff cover and lube locker, so you wont have to do this again.
1969 Cadillac Deville 7.7 Big Block
1978 Ford F-150 6.4 FE
1993 Ford Bronco 5.8 Windsor
1994 Ford F-250 7.3 Powerstroke
2016 Ford F-250 6.7 Powerstroke
UNIMOG-GUY
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Re: Leaking rear differential

Post by UNIMOG-GUY »

Here's the company that I'm buying my diff covers from for my CUCV (Dana 60/GM14bolt):
www.greatlakeoffroad.com/

Several reasons I decided on this company:

1. Lifetime guarantee. PERIOD. No questions asked you break it they replace it. Need I say more?

2. Customizable. I only ordered mine with the optional drain plug and counter bored mount holes however there are several other options to choose from. If you have ever tried to drain a 14 bolt to change fluid after you went wheeling then you know why this is a must have option.

3. The uparmored cover was given a bulletproof rating by JP Magazine. Will stop all the following ammo rounds: .454 Casull, .460, 7.62, .303, .450, and finally 22-250. This actually doesn't matter to me at all but thought I would include it for fun. Here's the article should you want to read it: http://www.fourwheeler.com/how-to/trans ... roof-test/
1965 Mercedes Benz Unimog 404 w/ MB-A 7 ton PTO winch and crawler gears for 413:1 crawl ratio, LPG
1986 Chevrolet CUCV M1008 FOR SALE
1986 Chevrolet CUCV M1028 w/ snowplow and H1 rims and 37" tires FOR SALE

An original member of the SC4WDA.
UNIMOG-GUY
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Re: Leaking rear differential

Post by UNIMOG-GUY »

Here is a coupon code for Great Lakes Offroad for 10% off your purchase.

PIRATE10

You have to create an account to be able to use it.
1965 Mercedes Benz Unimog 404 w/ MB-A 7 ton PTO winch and crawler gears for 413:1 crawl ratio, LPG
1986 Chevrolet CUCV M1008 FOR SALE
1986 Chevrolet CUCV M1028 w/ snowplow and H1 rims and 37" tires FOR SALE

An original member of the SC4WDA.
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