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Oil leak from front Diff on 95 ZJ 4.0L advice needed

Hey folks, I was under the car while changing the oil this morning and noticed a leak from the front axle Differential housing the oil stream is about 2 inches wide and goes from the U joint to the Housing (back to front) Now cannot tell if the joint is leaking or if the Gasket on the housing is the source. Has anyone encountered this before? Any tips to help determine the source? If the U Joint is leaking, is this an easy DIY job? Is the gasket easy to change?

I have been enjoying working on this Jeep since I got it, but I am no Mechanic, so bear with me.

Cheers, Paul

1995 ZJ 4.0L Limited Selec-trac
Reply to
Paul Tremblay
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You need to check the oil ASAP.

If there is still oil in it and it doesn't drip a bunch when sitting in the driveway, then it is the pinion seal leaking.

It is my belief that the new seal has to be put in by a professional drivetrain mechanic. I had a 'jeep' shop change mine and either it was just worn right out at 135000 miles or they destroyed it by hammering the pinion back on with their impact gun. $500.00 later at a drivetrain place and I am good to go.

Then you need to ask 'why' it's leaking. Bad u-joint vibrating or worn out pinion bearing? I think it is kinda a waste of time to change a seal that's only going to last 6 months or so because the bearing or u-joint are still worn causing the movement.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

Paul Tremblay wrote:

Reply to
Mike Romain

Oh, also mud is a good way to find the leak. Go get it muddy, let mud dry and drive it. The leak will be very obviously fresh at one point.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

Paul Tremblay wrote:

Reply to
Mike Romain

Thanks Mike, there is no puddle in my driveway. and the last time I was under the car before this morning ( 1 month) there was no oil on the diff. I will do the mud test and see what results I get. Meanwhile I will top up the oil also to gauge the rate of loss.

Cheers,

Paul

Reply to
PT

Sounds to me like the yoke seal. My rear Dana-44 did that too. It was just coated in oil all over the bottom of the diff. It wouldn't make sense, after all, for the oil to run UP the housing to the ujoint if it was leaking from the vertically lower diff cover's edge.

Anyway, it's an easy fix (apparently...I didn't do it, but was told it was...I just said heck, I've been wanting to do lockers and gears, why not now? lol) to change out that seal. You shouldn't have to mess with your gears or anything. You just disconnect the driveshaft, pull the u-joint yoke, and change out the seal with a new one. (Sorry if I'm over-simplifying, but that's how it was told to me, and like I said, I didn't do it myself.)

Reply to
Bob

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