Gearbox Oil Leak...Help

[foxy600]

I have just noticed a small oil leak from the gearbox, I thought it was an engine leak to start with until I realised the spots on the garage floor were too far back!
My question is I really cant afford an expensive gearbox repair at the moment, has anyone tried the Wynns gearbox stop leaks product?
Is it worth giving this a go? I know it is fairly simple to add to the gearbox by removing the manual top up plug, and its around £5.99. Apparently it is supposed to make the gear change a bit smoother too, and that can't be a bad thing on an S!!!

Any help would be appreciated

[tvrgit]

foxy600 said:

I have just noticed a small oil leak from the gearbox, I thought it was an engine leak to start with until I realised the spots on the garage floor were too far back!
My question is I really cant afford an expensive gearbox repair at the moment, has anyone tried the Wynns gearbox stop leaks product?
Is it worth giving this a go? I know it is fairly simple to add to the gearbox by removing the manual top up plug, and its around £5.99. Apparently it is supposed to make the gear change a bit smoother too, and that can't be a bad thing on an S!!!

Any help would be appreciated

Are you sure it's gearbox oil and not clutch fluid?

Never tried the Wynns stuff - what I did try (not on this car but before) was stuff called Oyltite or something similar. You can buy it from Frosts. Hang on... yes here it is:

http://auto.frost.co.uk/search?w=oyltite

It's like a Pritt stick, you clean the gearbox up, find where the leak is coming from (that might be the hardest bit!) and then rub this stuff in. It does work, IF you rub it into the right spot!

The Wynns might be easier and cheaper though.

[mep12345]

Personnally I wouldn't trust these types of products other than as an emergency repair although many people will. If they are designed to stop a leak they must "block" the leak path in some way. Whilst the gearbox operates on an "oil bath and scoop principle" and doesn't have any narrow oil pathways I would prefer to conduct a proper repair than risk reduced lubrication.

However you haven't given much detail other than "too far back to be engine". Where is the leak from? If coming from the rear of the box it could be prop shaft wear as the seal here is formed by the prop shaft's tight fit into the output shaft hole (pull out prop and tip box and the oil just pours out) although I think there is a seal inside that prop goes into that requires box stripping to replace. The front seal (inside the bellhousing) can be accessed without stripping the box fully, but it must be out of the car. It could of course be coming from the access cover on the top (held down by 12 (IIRC) bolts). The issue may not be as bad as you think - you just need to narrow down the area a bit before panicking.

It could of course be coming from the diff?

Mark

ps I would use something like TVRgit suggests as this is applied outside and doesn't go into the oil

Edited by mep12345 on Friday 25th July 17:35

[steve j]

If it is leaking from the rear seal where the propshaft fits, that seal can be replaced in situ without a gearbox strip, I recently did mine.

[steve j]

Forgot to add I`ve got a spare seal if you require it.

[greymrj]

I am afraid I am old enough to remember when almost every car had some form of oil leak and the routine was to have something underneath to
keep the garage clean and to give us an idea how often we needed to top it up. Maybe you are just too used to modern cars! It was hardly unusual for these boxes to give the odd leak when they were 'current'.
Unless if is a bad leak I really wouldn't be that concerned, they are not hard to top up. One thing I would check though is that it isn't overfull, it is actually supposed to be a couple of mm below the filler level and if the car wasnt level when filled it could be out and that can lead to leaks from the tail shaft.
There are not many places it is likely to leak, the most likely is indeed the propshaft seal and they are fairly easy to do. If however it is coming from the bellhousing (the bottom front of the gearbox)then it would be a different proposition.

[mep12345]

steve j said:

If it is leaking from the rear seal where the propshaft fits, that seal can be replaced in situ without a gearbox strip, I recently did mine.

Thanks for correcting me Steve, my oil seals (all of them) were changed during the gearbox rebuild and the grandada manual that I have didn't describe the change procedure for the rear one but the pictures appeared to show it well recessed inside the box. A method for doing this would be good (with pics if possible) if you could write one and email it to me ([e-mail]) with the pics I'll add it to my website for all to use.

Cheers

Mark