Gearbox fluid changed and now leaking!

[S6 Devil]

I recently had my mechanic change the gearbox fluid on my XJR. I provided the correct fluid and gasket, filter and O ring, all from Mercedes.

I had noticed fluid spots on my drive over the past couple of days.
I just arrived at work and noticed an acrid smell and smoke coming from the engine bay. The engine sounds and was running fine so I am assuming it is gearbox fluid burning. I have just moved the car to find oily spots under the car.

Any thoughts why it would be leaking?

[Cecil]

Not sure if it helps,

I had a gearbox service done on my X308 XJR not long after I got it, late 2007 afterwards if I kicked down at speed, fluid was escaping via the seals on the electrical connector to the gearbox, and causing a major smoke screen out the back, I got these replaced too, and more recently have had the electrical connector itself and seals changed, due to a weep. Only a 40 odd quid part on top of the gearbox service.

Out of interest which fluid did you supply, and what colour are the drips, if you dab them onto a bit of white paper?

[S6 Devil]

Thanks Cecil, that does help, I'll contact my mechanic tomorrow.

Do you have part numbers for the seals and the electrical connector to the gearbox?

I used the Mercedes 722.6 automatic transmission oil. The fluid is clear, well a light brown colour.

Edited by S6 Devil on Monday 7th March 23:43

[Cecil]

Sorry no part numbers, fluid should be red, IIRC

[S6 Devil]

Ah, that indicates that it could be engine oil. I will get the car to the mechanic asap! Thanks.

[NormanD]

Has it been overfilled

You can't get all the oil out so no good filing with the full capacity amount

Also it has to be checked when the gearbox is at the correct temperature

Seeing there isn't as dipstick in the gearbox did he use one also if not familiar with the gearbox can easily not dip correctly

[S6 Devil]

NormanD said:

Has it been overfilled

You can't get all the oil out so no good filing with the full capacity amount

Also it has to be checked when the gearbox is at the correct temperature

Seeing there isn't as dipstick in the gearbox did he use one also if not familiar with the gearbox can easily not dip correctly

I bought a dipstick and gave him the instructions that were sent to me in an article. He put just over 7 litres in, does that sound too much?

He is a very experienced Jaguar mechanic so I would be surprised if he got it wrong but it is possible that it's been overfilled.

I'm just wondering if it's a cam cover gasket as the fluid seems to be clear rather than red. It could also be an oil weep at the gearbox electrical connector. I will report back when I've found out.

[Piersman2]

S6 Devil said:

I bought a dipstick and gave him the instructions that were sent to me in an article. He put just over 7 litres in, does that sound too much?

He is a very experienced Jaguar mechanic so I would be surprised if he got it wrong but it is possible that it's been overfilled.

I'm just wondering if it's a cam cover gasket as the fluid seems to be clear rather than red. It could also be an oil weep at the gearbox electrical connector. I will report back when I've found out.

Er... Are you sure, if the fluid is clear, that it's not just condensate from the air con system? You'd be surprised how many times people have told me over the years that my Jags have been leaking when it's only been condensated water dripping off the condenser.

Gearbox fluid drips would be red/pink in a tissue.
Engine would be brown oil
Cooling system would be green.
Water would be.. er.. clear.

Although I did have a leak on my old XJR gearbox, which was difficult to be sure what colour it was so worth getting checked out anyways.

[drummerboyXJR]

That will almost certainly be the aforementioned electrical connector sealing ring. If you go to Merc 722.6 forums its a very common prob. Changed mine out, Merc part not too pricey.

[S6 Devil]

I saw the mechanic this afternoon. He rechecked the gearbox fluid level to find that it was overfilled by a considerable quantity. He has drained about a litre. I will see how things go, seems fine this evening on the way to work and no more smoke.

[NormanD]

S6 Devil said:

I saw the mechanic this afternoon. He rechecked the gearbox fluid level to find that it was overfilled by a considerable quantity.
He has drained about a litre. I will see how things go, seems fine this evening on the way to work and no more smoke.

Result then

I please I was of help.

[S6 Devil]

Thanks Norman and also for the info about your Indy. Cheers!