My recently-purchased MY 21.5 D350 occasionally smells of burning rubber after a gentle drive I can't see anything out of place around the exhaust and there's not much to see around the engine even with the cover removed. There are traces of old oil on the heat shield around what I expect to be a turbo on the RH sde of the engine in the vicinity of the exhaust manifold but it doesn't appear that the oil came from anywhere above.

A doubht that a DPF regen would smell of burning rubber.

Any suggestions? D350 SE Carpathian Grey D5 19" rims