02J transmission leaking after overfill

[crisp006]

Hi guys.

I recently changed the gear oil in my Jetta with an 02J transmission. I added about 2 litres but did so with the transmission out of the car and at an angle, so was not able to reference the fluid level by way of the fill plug.

As it turns out, the transmission must not have 100% drained as it has been slowly leaking (excess) gear oil and, upon removing the filler plug, the transmission began draining gear oil. A total of probably 100-250mL drained out with the car *somewhat* level. It is on jack stands so it’s not perfectly level.

My question:

Although it has now stopped leaking oil, can anyone tell me how it would’ve leaked to begin with? As best I can tell it was leaking from the bottom of the bell housing where the transmission meets the engine.

I read that there is a vent near the top of the shift tower, but then read elsewhere that the transmission cannot drain from there unless the car is upside down...

My main concern is if the transmission would’ve vented the gear oil out in such a way that it would’ve oiled up the clutch... in which case I am going to have to begrudgingly take the transmission out and fix that issue.

anyone have any insights?

thanks in advance.

 

[BobnOH]

..............................snip...................................Although it has now stopped leaking oil, can anyone tell me how it would’ve leaked to begin with? ........................snip...................................

Perhaps it was high enough to leak out the vent. But it sounds like you're good. I'm sure you'll be keeping an eye on it.

 

[realslimshaver]

iirc im not an expert but i have had my transmission out when doing my clutch myself. other spots it could leaked would perhaps be the reverse switch or the speedo sensor. i think the offical transmission vent is in the shift tower

if it somehow leaked out the shaft seal (im not sure if that would happen or not) and is over the flywheel then you could perhaps spray some non chlorinated brake clean(chlorinated is harsher on plastics and rubber seals) in the flywheel timing inspection hole while someone cycles your clutch in and out
, i was using brake clean for a while when my rear main engine oil seal was leaking lasted me a few months before i could afford a replacement oil seal and clutch kit

 

[crisp006]

Hi guys, thanks for the comments. Update... it’s actually still leaking.

sigh. It’s only about 2 or 3 drops a day, but I figure it’d be better to sort this out now before putting the car entirely back together than to have to refill it every now and then (which is not as straightforward as refilling the engine oil obviously).

I’m thinking input shaft seal but I’ll hopefully know for sure once I take the transmission out and have a look. I’ll keep you guys posted.