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Discussion Starter · #1 · (Edited)
Have a 2002 Zee with only 13K miles on it. Low mileage is partly due to parking it over the winter months. I usually take it for a short jog around the neighborhood once every month or two if the weather is good and the roads clear.

I noticed the other day that there was a small oil stain under the driver's side of the differential. I don't recall seeing any oil on the floor prior to parking, I usually give the floor a scan to look for any kind of leakage ... so I'm wondering if it started leaking due to lack of use. Sometimes seals don't like it when the car just sits.

Anyway, I haven't determined if it's the axle seal or the differential side cover O-ring. I need to crawl under and take a good look.

Is the differential leak typically from the axle seal, or the side cover O-ring?

Has anyone had a small leak from the axle seal due to long term storage, and then it stopped after regular driving? If it's the side cover O-ring, I doubt regular driving will help at all.

My warranty is over, so this will be something I'll fix myself if need be.
 

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ZeeOhSix said:
so I'm wondering if it started leaking due to lack of use. Sometimes seals don't like it when the car just sits.
Nope, this is a common problem and is more due to wear than sitting.
ZeeOhSix said:
Is the differential leak typically from the axle seal, or the side cover O-ring?.Has anyone had a small leak from the axle seal due to long term storage, and then it stopped after regular driving?
Axle seal, and it will only get worse, slowly.
I had mine done last fall while still under warranty and the repair price listed was like $287.00 Good Luck
 

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Complicating a determination is that the vent is on the top of the diff on the driver's side. So, if you parked it after driving it fairly hot, you might just be seeing drippage from oil that vented out.

Or... you could have an axle seal leak as mentioned. I had mine go out on me big time on my last race. Luckily the diff held together with only about a quart of fluid left in it at the end of the race (and I won). I'd suggest you get it fixed sooner rather than later. I was lucky. :cheers:
 

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Very common for the left axle seal to leak ! Mine went out at 4k. They replaced both seals at the same time !


Rob
 

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Discussion Starter · #6 ·
Subdriver said:
Complicating a determination is that the vent is on the top of the diff on the driver's side. So, if you parked it after driving it fairly hot, you might just be seeing drippage from oil that vented out.
I'm going to have to crawl under the beast and look closely at the vent area. I did do some high speed runs the few times I drove it during the hibernation period, so it's possible that there was some fluid puked out of the vent. Maybe a high speed run when the differential oil isn't fully hot could cause some to come out the vent? All though, I have done high speed runs before (with hot differential) and never saw any signs of leakage.

I've driven it a for a while and haven't seen any more evidence of dripping on the garage floor.

Thanks for the vent tip ... I'll check it out. :cheers:
 

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Discussion Starter · #7 ·
Rob1Vet said:
Very common for the left axle seal to leak ! Mine went out at 4k. They replaced both seals at the same time !

Rob
So why is it usually the left side (driver's side) seal that leaks? Aren't both left and right seals the same part?
 

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ZeeOhSix said:
So why is it usually the left side (driver's side) seal that leaks? Aren't both left and right seals the same part?

Yes but for some reason it shows first ! The left side has the longest output shaft from the diff !

Rob :D
 

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There is a TSB for differential axle seal leakage. Driver's side seems to be more predominant than passenger's side. There's a newer seal and also a revised cover. Do both. And be sure to have them scotchbright the axle shaft where it passes through the seal. Mine was showing a little corrosion and would have trashed the new seal in short order without a little preemptive cleanup.
 

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ZeeOhSix said:
I've driven it a for a while and haven't seen any more evidence of dripping on the garage floor.

Thanks for the vent tip ... I'll check it out. :cheers:
If you go for a drive of 30 minutes or so and do not see fluid the next morning, then the axle seal is probably not leaking. When you crawl under and look at the spot it's leaking from, it will be quite clear where the fluid is coming from. Good Luck.
 

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I've replaced 4 seals now (different cars) and in each case it stopped the leaking. I've put 4000 miles on my car since the seal change and it's still holding up so the improved three lip seal seems to do the trick. It's an easy DIY fix if you can turn a wrench.
 

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Discussion Starter · #12 · (Edited)
*** UPDATE ***

I finally had a chance to crawl under the beast tonight and take a close look at what was going on with the leak. I have been driving it for the last few days, and have not seen any new oil on the garage floor ... so that was a good start.

After safely jacking up the ass end, I got under with a good flash light for a look see. I did not see any signs of oil leakage out of the left axle seal, but only some residue collected at the very bottom of the left side cover. I then stuck my hand way up on the top left side of the differential to feel around the vent. There was some old grimy residue up there, so I'm thinking it must have puked once when I did a high speed run a week or two ago. I think the differential was still relatively cold (but engine was hot) when I did the run. I'm wondering if maybe the oil was still pretty thick and a little bit was forced out the vent with the high speed action.

It looks like if some oil does come out the vent that it will flow down the back side of the differential and follow the seam of the side cove all the way down the back side and then drip off the bottom of the cover.

Anyway, I cleaned everything up. I think I lucked out and it was just a little vent puke residue. :thumb: :cheers:
 

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I just had the left rear seal repair done at 18,000 miles by the dealer under warranty. I noticed oil in the area 10,000 miles earlier but tech said that it was not a problem.According to the repair order there is a new TSB to solve this problem, including a new seal.
 

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ZeeohSix,
I recommend you keep a very close eye on it. The downside is that if you have lost fluid out the axle seal it may be less susceptible to leak as the fluid level is lower, but it will not get better. If your diff runs of out fluid it will not be good as there is no temp gauge or low level warning.

I would clean it all up very good and check it for a while. :cheers:
 
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