Leaking diff

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jimf
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Post Tue Jan 15, 2013 1:31 pm

Hi folks,

I have traced an oil leak from my diff to what looks like a small seep from casing cover. Can this be removed and the gasket replaced without fully removing the diff from the car. Is it a big job?

Thanks, James
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daimlerman
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Post Tue Jan 15, 2013 1:34 pm

jimf wrote:Hi folks,

I have traced an oil leak from my diff to what looks like a small seep from casing cover. Can this be removed and the gasket replaced without fully removing the diff from the car. Is it a big job?

Thanks, James
Rear cover can be removed with the diff in situ,drain the oil first :mad:
then support the diff with a jack and remove the rear mounting bolt,then unbolt the rear cover.Do not forget to unplug the speedo drive connector... :o:
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Brianmoooore
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Post Tue Jan 15, 2013 1:40 pm

The very first thing to do is to undo the filler plug, just in case it doesn't want to undo, and you end up with an empty diff. with no easy way of filling it.
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jimf
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Post Tue Jan 15, 2013 2:57 pm

Excellent guys, thanks for your quick responses. While I'm on the subject, anyone know off the top of their head what grade and how much oil is nescessary and is the gasket a dealer only item.
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daimlerman
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Post Tue Jan 15, 2013 3:06 pm

Last diff gasket I bought from the stealer was less than a pound!

Open,small case diff uses about 2 pints of gear oil,80/90 or thereabouts.Pay you to check in the wiki for quantity,though,I buy gear oil in 5 litre cans and use a large syringe to inject it! :D
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Post Tue Jan 15, 2013 3:09 pm

there are specific oils for LSDs, I was recommended to use a Castrol option by Opie Oils, can't remember the exact grade, but you'll find it on their website.
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jimf
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Post Tue Jan 15, 2013 3:11 pm

Just had a quick look, need to determine if my car has LSD or not.
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blackE30indy
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Post Tue Jan 15, 2013 6:04 pm

on your diff there should be a metal tag,clean it up,if it's a LSD it should have a s on the tag
Before the ratio(number)
If you can't read the tag,jack the rear end up,and spin one tyre around,the other should turn the same way,if it does, it's a LSD,that's the way to check if it's got a slipper I believe :D
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jimf
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Post Tue Jan 15, 2013 7:44 pm

The car is already off the deck so when I spin one wheel the other turns the opposite way, this is a standard diff right?
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blackE30indy
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Post Tue Jan 15, 2013 7:46 pm

The other side wheel should turn the same way,if it does
Then it's a LSD :D
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blackE30indy
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Post Tue Jan 15, 2013 7:46 pm

If it turns opposite then it's not :(
daimlerman
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Post Tue Jan 15, 2013 7:48 pm

jimf wrote:The car is already off the deck so when I spin one wheel the other turns the opposite way, this is a standard diff right?
Reads like an open diff.... :cry:
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blackE30indy
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Post Tue Jan 15, 2013 7:52 pm

No way you can look at the tag,too confirm
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blackE30indy
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Post Tue Jan 15, 2013 7:53 pm

always sucks when you bought a car with a slipper,and it ain't got one :cry:
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jimf
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Post Tue Jan 15, 2013 8:11 pm

I'm not actually bothered aboutnot having an LSD, I'm happy with the way the car drives as it is. What difference would it make? I was under no impression that it had a slip diff.

Just been under the car (bloody frozen now) No actual tag anywhere and the only numbers I could make out were BM 017 on the right of the case. There was writing on the left too but pretty much illegible. Pretty sure there were no s's though!
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blackE30indy
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Post Tue Jan 15, 2013 8:22 pm

ah cool,if your happy with how it drives,you wont notice a slipper
That much inless your doing some spirited driving
If you've ever put your foot down mid corner,and one wheel lit up,
With a slipper this wouldn't happen,as both wheels would be putting power
Down and gripping,for some reason it's quite hard to explain
Hahah :D
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jimf
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Post Tue Jan 15, 2013 8:27 pm

I get ya! too old for lighting up rear tyres these days. Actually thats a total lie and I do it every now and then.
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blackE30indy
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Post Tue Jan 15, 2013 8:30 pm

Ha ha,we all do :D