Burning oil smell on 7G Tronic

[ldare]

Hi,

I have a 2007 R320 (140k Miles) with a 3.0 v6 Cdi engine & 7 sp auto box.

For the past month I've noticed a burning oil smell when stationary on a hill. I don't know if the smell only exists when stationary or if when moving the smell isn't brought into the car. I don't seem to have lost any engine oil in the past month and when I smell the smell of oil a couple of times I've jumped out and stuck my nose under the bonnet but there's no smell from there at all. I've had quite a good look under the bonnet and don't see any wet areas, everything likes nice and dry.

I've also had a look under the car once home (not been able to smell the smell so much on level ground - could be coincidence tho?) and I can't really see the exhaust easily but from what I can see there's no obvious oil. The two hills that I'm stationary on, on the way home where I mainly smell this there isn't anywhere easy to pull over and look under the car. I've also smelt the smell on other hills so it's not the hills themselves.

My fear is that oil from the gearbox may be dripping onto the exhaust? Is this possible? Can I check the gearbox oil? Has anyone had similar symptoms? Is there anything I should try to spot?

Thanks
Louis

 

[John Laidlaw]

Could be a number of things. Any performance loss?

 

[ldare]

Could be a number of things. Any performance loss?

I don't think so? But I don't drive fast

 

[00slk]

If the 7g box is similar to the 5 speed auto, it could be the gearbox adaptor switch, we had the same symptoms and had the parts changed, no more oil burning smells

 

[Wighty]

You need to have someone look under the car with all the body shields removed .

 

[malcolm E53 AMG]

Sounds like the gearbox sump is leaking slightly. If you haven’t had your gearbox oil changed in the last 40k miles now seems like a good time to have it done but regardless you need to have the gearbox inspected and yes it will drip on the exhaust especially when the car is not level

 

[ldare]

Took it to a diesel engine specialists who said they work on these all the time, in fact they had another one there! They said it was the oil cooler and had a brief look under the hood and saw oil around it. They said leave it and live with it. Does that sound right?

 

[malcolm E53 AMG]

It’s a big job the oil cooler sits at the top of the block between the vees and has the manifolds and turbo above it and the injector rails so min £500 (10hrs Labour) to replace 2 seals which cost £10
There are probably hundreds out there with seeping seals but if the oil is getting on the exhaust probably better to get it done.