A few years ago (more like 7-8 years ago) my dad replaced the fluid in the diffs in his 93 GMC Sierra. He put in synthetic and the front dif started leaking like crazy. The rear leaked too but not as bad. So he replace it with conventional again. I don't understand why the synthetic fluid would cause a new gasket to leak. I would like to change the fluids in my Jeep with synthetic but with my dad's previous experience I don't know if I should. Anybody else have problems with leaks using synthetic fluids?
Does synthetic cause leaking?
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I have had no experience with leaks caused by synthetic.
I have a 98 DOHC Neon with 175,000 kms running Mobil 1....and a 2001 Neon with 75000kms running on M1 as well.
I have heard it may worsen leaks that already exist because it cleans out the crud...but does not cause leaks.
Perhaps this is just a myth.
I have a 98 DOHC Neon with 175,000 kms running Mobil 1....and a 2001 Neon with 75000kms running on M1 as well.
I have heard it may worsen leaks that already exist because it cleans out the crud...but does not cause leaks.
Perhaps this is just a myth.
I have heard a lot about early 90's GM truck diffs leaking. I'm thinking GM had issues.
You shouldn't have an issue in your Jeep.
You shouldn't have an issue in your Jeep.
MolaKule
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The only leaking I have seen is due to small seepage around the filler plug on Nissan and other vehicles, since synthetic fluids flow better, creep more efficiently, and with less surface tension.
It only takes a few milliters of gear lube to spread and wet plugs and surrounding cases.
You didn't say from where it was leaking?
It only takes a few milliters of gear lube to spread and wet plugs and surrounding cases.
You didn't say from where it was leaking?
Let me start by saying I have had overall good luck with syn gear lubes but I have also had 2 isolated instances of leaks.
I had the same thing happen on the front diff of a '98 Tahoe 4x4. Truck had about 50k miles on it at the time (if I remember right), simple drain and refil with Royal Purple and it started coming out of the pinion seal. It never leaked before then. I changed the pinion seal to be safe, then refilled with dino and didn't look back.
The transfer case on a Toyota 4x4 leaked also, that one I just drained out the Redline I put in and added some dino and it went away.
Like I said those are my experiences, didn't happen everytime I used syn. I've run it in at least 10 other vehicles without issue.
On the rear often times leaks occur because its hard to get those stamped steel diff covers to seal once they've been pryed open. Sometime its tweaked just enough to cause a leak.
I prefer a cover with a drain plug for that reason.
I had the same thing happen on the front diff of a '98 Tahoe 4x4. Truck had about 50k miles on it at the time (if I remember right), simple drain and refil with Royal Purple and it started coming out of the pinion seal. It never leaked before then. I changed the pinion seal to be safe, then refilled with dino and didn't look back.
The transfer case on a Toyota 4x4 leaked also, that one I just drained out the Redline I put in and added some dino and it went away.
Like I said those are my experiences, didn't happen everytime I used syn. I've run it in at least 10 other vehicles without issue.
On the rear often times leaks occur because its hard to get those stamped steel diff covers to seal once they've been pryed open. Sometime its tweaked just enough to cause a leak.
I prefer a cover with a drain plug for that reason.
My 96 GMC rear diff started leaking within the first 500 miles.It was fixed under warr.At 50,000 miles I changed both diffs to Amsoil and now I have 118,000 miles with no leaks in either diff.
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