Gearbox leak F20

[Iain]

This is annoying me now, every time I go under the car there's drips of transmission fluid on the diff cover plate and lowest bolt heads

I've replaced the seal twice, with sealant, and replaced the diff cover plate itself once, and its still leaking

It doesn't feel wet just below the inner CV seals so assume they are not leaking? Nor does it look wet under the level plug on the side.

So wtf can it be

[John]

thread lock on threads?

[Iain]

No does it need it? Can it drip down past the threads?

[John]

iirc when i used to work at vauxhall, all diff pan bolts used threadlock and i'm guessing for a reason, Might be worth a try?

[Iain]

I'll give it a go! Cheers

[nova_saloon]

you sure you've not over filled it as iirc the ispection hole is covered up by the engine mount! doi!

[Iain]

I can just squeeze the level plug out. If its over filled where would it be coming out? I refilled it with just over 2L and ensured it was up to the level hole but it may have gone over when I refitted the bolt I guess.

[John]

if it's overfull, surely it would breathe it out?

[AlexW]

Or do like mine did, and not be any different.

Sure its not cracked somewhere?

[Iain]

I fitted a new diff cover plate thinking the old one may be cracked. Haven't seen any cracks and it doesn't look that wet above the cover plate either...

[Mazz]

iirc they only hold 1.9l, so maybe just pushing it out..?

[Iain]

I'm sure my Astra Haynes said 2.1 litres. You'd expect it to push it out the breather or a seal like John said tho?

[John]

there's no scores/mark on the g/box face?

[Iain]

I had all the internals out and cleaned the entire casing and saw nothing that concerned me at the time.