how much oil leaking from the rear oil seal is acceptable

if you have a manual transmission, you can't have any leaking from the rear seal, or it will soon ruin your clutch.

could it be from droppin the tranny or no?

Doug maybe that was making your clutch slip, i would change the rear main seal. Also look at your oil pan gasket on my red z it was leaking in the back and making its way into the bellhousing...

There is a seal on the tranny input shaft and on the back of the engine. So no, there shouldn't be ANY oil in there. I always replace both the rear main engine seal AND the front tranny seal whenever I have a tranny out of a car. Again I feel the dealer seals are MUCH better than the aftermarket ones, had too many problems with leaks when I used something else.

oil pan is leaking on the left, engine was just rebuilt too!. Just changed the oil also! dammit. I have a 5 speed though that is whining in 2nd and third i think the guy said. So im going to be replacing some bearings, just dont know which ones in the tranny. I am putting a 2+2 flywheel in it with a 79zx 5 speed tranny, any advice? can i use the fork from a 280z tranny?

Make sure you have a 2+2 release bearing collar.

The 2+2 release collar is 48 mm long. The regular collar is 52 mm long.

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