Transmission leak - advice please

[RickMM]

Hi,
Wasn’t sure whether to post this here or in the technical section. I have searched and didn’t come up with anything but happy to be directed to the right place if I’ve missed something.

Late 2012 C63 just been in to main dealer for B service (45k miles). The video report shows that there’s a slight leak from a hose where it joins the transmission oil cooler (presumably not too big a problem to deal with?). However, there’s also a quote “larger leak from the rear area” (cue the schoolboy jokes ) which seems to be coming from the transmission again. It’s not clear exactly where this second leak is coming from, but the dealer has said that they would need 5hrs labour to diagnose the problem by dismantling the gearbox ! The tech suggests that it may be coming from the main seal between engine and gearbox, although it looks as though it might just be from the transmission pan/filter gasket underneath. These were rated as "amber" rather than "red".
I guess I’d just like to know whether these issues are common, and what the usual remedies entail?
The car still has Tier1 warranty, but the service rep said that seals are not covered (assuming that’s what’s leaking). So the story is that I’d have to front-up the initial 5hrs labour to enable them to diagnose, and then they would try to get this sorted under “goodwill” from MB (don’t know how likely that is?). As things stand, they've suggested that I bring it back in 1000 miles for a further inspection.
Interestingly, there’s been no previous sign or warning of this (tranny works fine) and not a drop of fluid to be seen where it’s regularly parked, although there did seem to be quite a lot under the car on the video.
Any help appreciated

 

[whitenemesis]

Possibly the pilot bush leaking? Do the later 'boxes suffer the same way as the older 5G units?

 

[C63RAA]

Had a similar problem on mine (2013 C63 wagon 26.000 miles). They found it when it was in for a service. Booked back in got it back two weeks later they had to take the engine out. Fortunately it was under warranty I hate to think what it cost.

 

[markjay]

I would take it to specialist first.

Apart form getting a more accurate diagnosis... if it does turn out to be an engine-out or tranny-out job, you want to pay the lower hourly rate and get the better service that a good specialist can offer.

I don't know where in the UK you are based, but I recommend these forum sponsors:

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Contact | Mercedes Benz & Smart Specialists | Prestige Car Service | Horndean, Hampshire

 

[RickMM]

Thanks Markjay,
A second opinion is always a good idea. MSL in B/ham is probably easiest for me.
However, if it does come to having to get something major done, then it's a gamble between cheaper indy prices versus the chance of getting a goodwill gesture from MB via a main dealer!
Hope it doesn't have to be either

 

[DSB SL AMG]

MSL would definitely be worth a second opinion, can you post stealer technician video report link of issue...?

Thanks Markjay,
A second opinion is always a good idea. MSL in B/ham is probably easiest for me.
However, if it does come to having to get something major done, then it's a gamble between cheaper indy prices versus the chance of getting a goodwill gesture from MB via a main dealer!
Hope it doesn't have to be either

 

[RickMM]

Hopefully this should do it (although you may have to copy n paste)

https://mercedes.citnow.com/vtM3rVNTWQT

 

[DSB SL AMG]

Link works fine...noticed an error at the end, he missed ''the money extraction team'' will be in contact with you shortly

Am sure others will comment on the leak...

Hopefully this should do it (although you may have to copy n paste)

https://mercedes.citnow.com/vtM3rVNTWQT

 

[fordgt40]

I had a gearbox leak after a B service on my w204 C63 it transpired it was because they hadn't fitted the gasket correctly after taking the gearbox pan off, it took 2 visits to cure it , they never admitted responsibility, I will not insult your intelligence as to the excuses I was given as to why it happened.

 

[RickMM]

Interestingly, having been told by the MB service dept that this issue is NOT covered under the warranty, I've just checked the wording in the warranty document and it states:
"Also included are: Crankshaft front seal, camshaft oil seal, auxiliary shaft oil seal, gearbox rear output seal, drive shaft seals, differential pinion seal and any oil seal or gasket where removal of the engine, gearbox or differential/drive unit is essential in order to effect repair."
Surely this must include the offending parts here? (except maybe sump gaskets)
Am I being fobbed off ?

 

[Steveml63]

Interestingly, having been told by the MB service dept that this issue is NOT covered under the warranty, I've just checked the wording in the warranty document and it states:
"Also included are: Crankshaft front seal, camshaft oil seal, auxiliary shaft oil seal, gearbox rear output seal, drive shaft seals, differential pinion seal and any oil seal or gasket where removal of the engine, gearbox or differential/drive unit is essential in order to effect repair."
Surely this must include the offending parts here? (except maybe sump gaskets)
Am I being fobbed off ?

Yes!!!

 

[DSB SL AMG]

More than likely...rather than by phone, i would print this section of the policy and pay Mr Stealer Service Dept a visit regarding warranty claim...

Note warranty claims are agreed fixed fees with MB, obviously outside of this they can charge standard stealer rates direct with the customer...

"Also included are: Crankshaft front seal, camshaft oil seal, auxiliary shaft oil seal, gearbox rear output seal, drive shaft seals, differential pinion seal and any oil seal or gasket where removal of the engine, gearbox or differential/drive unit is essential in order to effect repair."
Surely this must include the offending parts here? (except maybe sump gaskets)
Am I being fobbed off ?

 

[RickMM]

More than likely...rather than by phone, i would print this section of the policy and pay Mr Stealer Service Dept a visit regarding warranty claim...

I might just do that. Thanks for the support

 

[markjay]

If the dealer replace the sump gasket under warranty then they may want to re-use the ATF (ie drain and collect, then use same ATF to refill).

In this case I would be inclined to pay for new MB ATF (possibly also filter?) and have a partial ATF change/refresh (ie not including the torque convertor and transmission oil cooler).

But this is of course down to when/if the ATF was last changed and how long you intend to keep the car.

 

[RickMM]

Got stung for the ATF change 12 months ago at the last service, so all should be good there?
I also had the AC condenser changed under warranty about 4 months ago, and there was no mention of any oil leaks at that time.
Plus, there's no sign of anything having dripped onto the drive where it's parked, despite what looks like quite a bit of oil under the car in the video (link above)

 

[Steveml63]

Got stung for the ATF change 12 months ago at the last service, so all should be good there?
I also had the AC condenser changed under warranty about 4 months ago, and there was no mention of any oil leaks at that time.
Plus, there's no sign of anything having dripped onto the drive where it's parked, despite what looks like quite a bit of oil under the car in the video (link above)

Hi,
I would be inclined to try and clean all the oil off and see how long it takes for some more to appear.
That will give you an indication of how bad the leak is - and confirm whether the dealer is pulling a fast one (putting oil on outside of transmission to masquerade as a leak!).
Cheers
Steve

 

[Captain Smerc]

My 2012 model had this issue , it was spotted at service time . Fixed under warranty which had only a week left ! Said they had to drop the gearbox out . Got it back inside 2 days , good work MB Southend

 

[RickMM]

This is what I'm being told at the moment (drop and strip the gearbox to diagnose the problem) although initial comment was that "seals" are not covered under warranty.
I think I might have to disagree... or go to a different dealer !

 

[PhilT]

Did you ever get this sorted?

 

[RickMM]

Did you ever get this sorted?

When I took it back after 1000 miles for a check (as suggested by the dealer) they just said "wait and see, if it gets worse then come back", so it couldn't have been that bad. There is never any sign of oil/fluid on the drive when parked, the transmission works perfectly, and nothing has been done !