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draining oil from overdrive on a BJ7

Roberte

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Is it necessary to drain the oil on a BJ7 overdrive seperately from the transmission drain and refill? On my parts diagram I show a drain plug but the only plug it shows in the top has a plunger etc attached to it. I don't have my car available to me or I would check the unit myself.
 
Generally there is a large Brass plug on the bottom of the overdrive that will allow you to drain it.
 
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Drain both (xmsn & ovd) but refill thru transmission dipstick hole. To get an accurate reading on the dipstick afterwards, drive it around the block, engaging overdrive a few times, then recheck the level (while the car is level too).
 
On a related question, one of the many common oil drips I have on my BJ7 is the OD brass drain plug. I changed the trans & OD fluid last year and cleaned the OD filter screen. Any suggestion for sealing the threads on the brass drain plug would be appreciated. Teflon tape or other sealers?

Also, any idea on fluid volume to top up a drained OD?

Tom Troy
 
Permatex teflon thread sealant might help some. Unlike teflon tape, it's non-solid and should be less inclined to block small passageways should it migrate. I use synthetic and even with a fresh fiber washer--which always seem too hard to seal well to me--and sealant I still lose fluid.

IIRC, it takes a little over 3qts to fill transmission and O/D, give or take. Try not to overfill.
 
Thanks. I will try Permatex and I agree that the fiber gasket seems too hard, I may also try to cut a replacement gasket out of softer gasket material.

The never ending quest to stop drips.
 
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