QuestionI own a 64 Pontiac LeMans with the 326 engine and the two speed Powerglide transmission. The transmission has been badly leaking now for six months and my mechanic has replaced the gaskets, tightened the pan bolts, and it still leaks. The fluid usually appears to only leak out after I park the car in my garage (It fills the drip pan I put under the car).
If you check the fluid when hot (after its leaked), and with the engine running, the fluid will barely register on the tranny dip stick. If you turn the engine off and let it sit, the dip stick will register a bit over full. Is this normal, or some indication that something else might be wrong and causing the fluid to leak out in such great quantity every time I park the car?
I only drive this car every seven to ten days, but when I do drive it, its for more than thirty minutes to an hour and it always has a chance to thoroughly warm up.
Do I go get another pan gasket and try it again (I've done that three times), or is there something else that might be wrong?
Thank you.
AnswerFirst, it should be checked ho idling. It is normal for it to appear overfilled after sitting since the passages inside the tranny that fill up when running, drain back into the pan.
Second, if it is the pan leaking then it should be obvious, and the shop that did it the first time should fix it free, you may have to take the pan off, check that the metal edge is free from warps and dents and then put a new gasket on with sealant on both sides of the gasket.
But I would try to jack the car and put it up on stands safely after driving it for a while. Then just get under it and wipe down the unit and stay there till it starts dripping.
It could come from the pan (unlikely if the first repair was halfway good. Also from the rear seal, a major leak place, but easy to spot, you didn't mention replacing that. It could come from the front seal in that case it would be leaking from the bell housing. Or maybe from the seal around the shift lever, or even from the vac canister, but if it was leaking, it would be sucking fluid into the carb and your car would smoking for mosquitoes. Check that there IS a vac line on the canister and if not, it could just pour out of there.
Chances are it is leaking when you are driving, but you don't notice it. is the underside of the car and driveshaft ect all wet with tranny fluid?
Sounds like you need to find a better mechanic/transmission shop. These Powerglides aren't all that exotic and most shops should be able to rebuild/seal them quickly and easily, and parts are still available.
But if you are getting tired of it, you can put in a more modern 3 speed tranny with OD that will not only make the car faster, but it will get better MPG. Check with the various GTO clubs for how to do this.
Don
Don
