c4 transmission seals
 

I have two leaks of transmission fluid from both of the differential locks.

The lateral (or transverse) lock leak is not too bad as it just wets the side and bottom of the transmission but doesn't actually drip.

The longitudinal lock on the other hand drips a drop every 3 seconds or so and has resulted in a 2 foot wide puddle of tranny fluid on my garage floor. (which also confirms that it's not brake fluid as that would surely have emptied the reservoir but it's still full!)

Through PET i've found the longitudinal lock transmission seal I think (part 2 in attached picture - part no 964 301 051 01) but am unable to locate a transmission seal for the transverse lock. And a final question: how hard is it to get the old seal out? I find it's usually alot harder to get an old seal out than the new one in!

Thanks

Think I may have found it - it's called a "bellows" in the PET. Part no. 928 332 051 02 (labelled 10 in the attached diagram which "clearly" shows where it goes :confused:).

I have the same problem. The locks are quite pricey so I've been holding off. I've disconnected the PDAS/ ABS plug in front so they stop leaking.

By the way, that's not tranny fluid, its brake fluid! Careful, brake pedal may suddenly go hard and you'll need to exert more force to stop safely. I would check and top up brake fluid before driving!

Definitely tranny fluid.
Reason one: my brake fluid is yellow, the leaking stuff is brown and higher viscosity than brake fluid.
two: the sheer volume on the ground would have emptied or at least set off alarms on the brake fluid reservoir (it's still near the max level as it was 6 months ago)
three: Just came in from the car being on the lift - separated the longitudinal lock from tranny (surprisingly easy when the car is 6 feet in the air!) and the stuff kept dripping from the tranny, the lock stayed dry. And i think i can feel a tear in the seal in the tranny.
I couldn't separate the lateral lock from the tranny and given the time of night i was disinclined to try and prise it off.

I think also the reason that the long lock is leaking alot more than the lat lock is that the lat lock is bolted into place with a gasket at it's base (no 3 in attached pic) whereas the lat lock is only held in by that clip.

Also found this picture that shows what i think is the leaky bellows for the lateral lock (no.4).

Alrighty, I may have been wrong then. I guess I had two problems happening ;)

I'm also interested in getting those bellows. But at the same time I'm not sure if it will cure my/our problem.

I opened up the lock and this is what I found inside. Looks like the outer plastic rings are broken and the cause of my leak. I wish I could get a solution because buying the part new ain't cheap. Then again is it possible the rings are supposed to be that way and all I need is the rubber bellows? Wishful thinking? ;)

http://i52.tinypic.com/2r6dvee.jpg

http://i55.tinypic.com/1610rqr.jpg

http://i55.tinypic.com/1zm0ciu.jpg

https://rennlist.com/forums/964-foru...ch-begins.html

yes, the two outer blue "seals" aren't actually seals but rather guides - that cut out is supposed to be there. Only the fully intact one in the middle is a seal.

Thanks for the thread link! Good stuff!

So it seems my middle seal is damaged and that is the cause because the rest of the thing seems fine.

It seems that that stupid little middle seal is impossible to replace. Didn't see a conclusion in that thread either. What a shame... I am leaking a small amount of trans fluid and a moderate amount of brake fluid every day, this sucks! Might have to just suck it up and buy a new one huh :(

you could resurrect the old thread and see if garrett et al found a solution?

the sulphurous odor in my garage was overwhelming this morning. good thing i put a pan under there to catch it. It'll be a week before local porsche gets the part in.

http://www.claron.co.uk/pistonse.htm

http://www.pastparts.co.uk

people like this might be able to help. Past parts resleeve brakes cylinders. part a15 on the claron site looks familar, combined square and round section ring. Surely a rebuild must be possible. Just a question of getting the right size and materials...

Just sharing what i found from a little googling. I have a c4, my 4wd locks are ok at the moment but this topic totally feeds my maintenance bill anxiety.

I replaced bellows, part #4, to stop the leaking on mine. The bellows keeps the fluid from leaking out of the case when the lock is removed. It is a compression fit in the boss by way if a spring wire clip inside the bellows.

how hard is it to remove with that spring clip inside it?
parts on order - just waiting for arrival.
the main leak on mine is the longitudinal lock (front end of tranny) but both are getting replaced.

The more I thought about it, I now recall that it's actually a thin, flat metal band. It's just presses the rubber bellows outward against the opening, kinda like the reverse of a hose clamp. It's easy to remove and install.

Need help on getting the longitudinal seal out. I've got a seal puller but the hook on it isn't long enough to get inside the opening to lever it out. I'm thinking i almost have to drop the tranny to get enough room to pull this little thing out. I've tried pulling on it with various right angle things (like small allen keys, and such) but can't get enough leverage to get it out. FWIW, the green arrow points to the offending tear in the rubber!

Any advice / tips ?

I'd give it a clean up with brake cleaner to try and get it dry of oil and then jam in a bolt or bit of tube, just big enough to get purchase on the rubber and pull/twist it out. Failing that I guess, grab at it with some long nose pliers - to get better access you could use some curved forceps http://www.machinemart.co.uk/shop/pr...ails/forceps-2

ok got the old seal out an tthe new one in. \now the long lock cylinder won't go back in. might have scratched the hole with the seal remover cresting a burr? IIRC it came out and went in smooth before.

oh well, gues i'l go back out there and continue hammering it until it seats itself. just needed to post to get it off my chest.

Definition of insanity: doing the same thing repeatedly expecting a different result.