Differential fluid?

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dcmeigs

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Does the differential get lubrication form the engine or the transmission?

I have a leak and it drains between the oil pan and differential and then drips to the floor from the differential. If I clean the differential and floor real well of an evening I will find oil on the differential and floor in the morning.

I'm wondering where is the leak?

The rapid **** guys topped up my transmission last year and it's still about right. I note that the fluid is red today, inspite of my insistance that they use motor oil. I guess those rocket scientists knew better than I what should be used in MY tranny. Be that as it may, the fluid on the ground is oil, not ATF.
 

91PDXmocha

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First things first , your differential is a part inside of your transmission . So your probably referring to the rear main seal . The seal between the engine and the transmission . You have to pull the transmission to change it thought so it's a big job . You could try and stop leak additive and see if it helps .
 

dcmeigs

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OK, understand now. Differential and transmission are integral using common fluid. I've never had one apart.

So, the engine has not been started in a week. (It's been up on jacks with the intake runners off) The engine continues to drip oil after that period of time. The oil level on the dip stick is between the marks. Would a rear main seal leak under that circumstance? Would an oil pan gasket leak under that circumstance? Wouldn't the oil be in the pan?
 
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Racer X

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If you've liberated a differential pin from the differential, the resultant hole in your transaxle will continue to leak whether you drive the car or not.

To be sure, there's a fill plug at the front of the transaxle, just below the ABS pump. If you remove the plug (3/8th ratchet and short extension) and feel inside, the fluid level should be just below the lip of the fill plug. Any lower and you have a leak. If you fill the transaxle to the normal level, and ATF leaks from anywhere else other than the axle seals, you've thrown a pin through the case.
 

dcmeigs

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I don't think I'm leaking from the transaxle. The fluid in the transaxle has been contaminated with ATF and has a red hue as you might expect. The leaking fluid is nice clean yellow motor oil. It pretty much has to be coming from the rear crank seal but that is difficult to square with the fact that the engine has not run recently. Yet I don't have any other ideas.

I'll replace the transaxle fluid soon but for now it's a handy aid to troubleshooting.
 

trainguy1989

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I don't think I'm leaking from the transaxle. The fluid in the transaxle has been contaminated with ATF and has a red hue as you might expect. The leaking fluid is nice clean yellow motor oil. It pretty much has to be coming from the rear crank seal but that is difficult to square with the fact that the engine has not run recently. Yet I don't have any other ideas.

I'll replace the transaxle fluid soon but for now it's a handy aid to troubleshooting.

The tranny uses ATF. The color SHOULD be red. Sounds like you have a bad rear main. In order to replace the rear man seal you have to pull the tranny.
 

kevinspann

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I think the year would depend on what fluid it should use (brass blocking rings vs. fiber lined) but definitely not motor oil.

What year is the car?
 

rubydist

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1. the differential is part of the transmission and the proper transmission fluid for both atx and mtx transmissions is atf, as has been stated. if you have verified that the trans fluid is in fact red, then your leak is not from the trans. it appears that the rocket scientists at the quick **** actually did know more about your car than you did.

2. the rear main seal will not continue to leak for a week of not being run. that makes your continual leak unlikely to come from the rear main (although it could be leaking too)

3. the only thing that should be leaking after a week of sitting is the oil level sensor in the oil pan. as you might expect, it should be in the oil if the oil level is proper, so if it leaks (and many of them do) then it will continue to leak even when the car just sits there. I would suggest taking a very good look at the oil level sensor.
 

turbosho

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I would suggest taking a very good look at the oil level sensor.

I would remember you are talking to the guy who thought the differential was the rear main seal.

It would probably be best to have him avoid any sort of wrench or even the hood latch.
 
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I guess those rocket scientists knew better than I what should be used in MY tranny.
You would be correct,they know what fluid goes in your transmission,you do not.
Use a high quality ATF in the SHO MTX transmission.
Do NOT use motor oil,gear oil or anything other than ATF!
 
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dcmeigs

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I think the year would depend on what fluid it should use (brass blocking rings vs. fiber lined) but definitely not motor oil.

What year is the car?

It's a 91 and I remember now that the oil change guys wanted to use gear oil instead of ATF and that was the issue. Brain fart; I stand corrected, the ATF is correct and it will remain.

The oil level sensor is leaking and I have one on order form SHO Sourse. Should be here any day. That leak is separate from the other.
 

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