Hot Hot smell from Rear (Diff?)

bryce86 · 13th September 2006, 00:06

Hello

Firstly Id like to introduce myself as this is my first post. Im Bryce, and Im from SW Scotland. I drive a Cooper S. Im also a Complete and Utter BMW fanatic!

Secondly, I have a question about my fathers car. He has an E60 M5, 2006. Its Silverstone II, black leather, and a few toys! He's covered 3k miles with it since he got it in March this year, so she's run in now - wow! It goes!

So anyway, my dad and I were out a run in it to town and back the other night, a round trip of only ~8miles. Took it easy heading in, to let her warm up, and on the way back in 'M' mode (500, EDC II, S5) he gave it a blast from 60 to 140ish, then let it roll back down to 80, then did the same again on the next straight. When we got back and the car was in the drive cooling off, before shut down, we noticed an awfully hot smell coming from around the diff area in the back end. This got us wondering, is this natural? Its his first M car.

When the car was in for its first service, the dealer noticed the clutch wasnt right so replaced it. I had wondered about this as it felt rough on moving off from a standstill at slow speed, but thought this was maybe just the style of SMG.

Also, there is occasionally a "clunk" noise from the back left wheel.

Thank you in advance!

bryce

ps. sorry about quality of pics, just taken with my phone.

unfoundhorsepower · 13th September 2006, 02:39

sorry way too many variables for me to guess...

JamesInLV · 13th September 2006, 07:30

Not sure about the "hot hot" smell. The clunk is normal...just the differential/final drive engaging. When you run in S5/S6, the gear shifts are so fast that they often jerk the differential around a little too and lead to the clunking sound.

The more instances of people reporting harsh or slow starts and getting clutches or transmissions replaces makes me wonder about my own car. On the other hand, the M5 and M6 I drove at a recent M Driving Exeperience operated very much like my own, so I don't think there is any problem on mine.

Manx M5 · 13th September 2006, 10:33

I had a very spirited drive home from work on fri night and when i shut her down she was stinking from the rear and the front.. It was the first time i had used L/C and driven hard with DSC off and in S6.

I actually thought it was the brakes/clutch more than the diff, but i didnt get underneath.. just laughed and went and got a beer!

4rotor · 13th September 2006, 14:45

Firstly, check under the car for leaks of any kind (look up under it with torch is best - on the bottom side of the floor, around the diff, gearbox, engine, etc.).

My car always stinks after a drive! But it was really bad after my 2 VANOS line failures, they hadn't cleaned it properly the second time (mind you there was a lot of oil all under the car). So I had that terrible oil smell for a while.

I do find that a spirited drive will make it smell, brakes, clutch, exhaust - and of course it is a bit of an oil burner so that it probable a factor also.

Is the clunk noise when driving around town? starting off? stopping etc.? - little more info.?

bryce86 · 13th September 2006, 22:00

Quote:

Originally Posted by JamesInLV

Not sure about the "hot hot" smell. The clunk is normal...just the differential/final drive engaging. When you run in S5/S6, the gear shifts are so fast that they often jerk the different...

I wasnt in S5/6 mode buddy, it was S1/2 driving around at low speeds (20mph), its only occasional, it sounds like a dry knocking (metal on metal).

First time I got a wiff of this burning I thought it was possibly the brakes, but on sunday there - the brakes were barely used.

It wasnt a spirited run at all, just two sprints (60-140) over a 2 mile stretch.

bryce