rear diff seals - how hard to replace

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Mar 29, 2002 | 05:09 PM

slowsix

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rear diff seals - how hard to replace

The rear differential seals on my 1988 F150 4.9 2wd are starting to go. I have never opened a rear differential before. How hard are these to replace? It is an open differential. Suggestions? Tips? Cost to replace at the shop is $200.

Mar 29, 2002 | 10:44 PM

PAUL_2

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rear diff seals - how hard to replace

Which seals , the axle seals or the pinion seal ? If you have leaks at all 3 then before you replace any check the vent , If its clogged it can cause all 3 seals to leak , the pinion seal being the easiest way for the pressure to vent . The vent is located on the left axle tube , its threads thru the brake line junction block & will have a rubber tube attached to it .

Mar 30, 2002 | 09:43 AM

slowsix

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rear diff seals - how hard to replace

I believe it is the rear axel seals. Some of the lube oil is draining to the brakes. As I understand it each axel has it's own seal and you need to pull the axel's to remove the seals. Any idea on how long it takes and the difficulty? Is it difficult or just a PITA?

Mar 30, 2002 | 12:32 PM

PAUL_2

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rear diff seals - how hard to replace

You ll have to remove the rear diff cover to drain the gear lube , Remove the brake drums . There is a bolt of the pinion lock shaft , remove it & the pinion lock shaft , slide the axle in & remove the C clip on the end of the axle . Now slide the axle out , pry the old seal out & lightly tap in the new seal . Lube the lip of the new seal & slide the axle back in . Repeat for the other side . Youll need 2 new axle seals , 3 or 4 Qts of gear lube , a tube of black Rtv . Its not a hard job , should take you about 2 hrs to complete .

Apr 1, 2002 | 08:06 AM

slowsix

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rear diff seals - how hard to replace

Thanks Paul.

Apr 2, 2002 | 12:10 PM

slave2dafords

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From: LeClaire IA

rear diff seals - how hard to replace

just to interject something.. fel-pro makes a rear end cover gasket get that and some spray adheasive alot easier and less chance for a leak.. i just got done replacing my axle seals easy job as long as you get the proper seals for the axles...

Apr 2, 2002 | 12:19 PM

cmlind

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From: Minnesota

rear diff seals - how hard to replace

It might not hurt to check or replace the bearings while in there. In my experience, I have had seals go out only when they were overloaded causing the bearings to heat up and fry. Also, only put in Ford(OE) bearings. THe aftermarket ones are sometimes not up to ford specs.