Advice please: smell from rear wheels...

Hi,

Today I made a bit of a fool of myself four weeks into M ownership...

I was drivng down a hill at 30mph in 3rd following two other cars when they both turned right at the bottom...I saw my chance for some hard acceleration and duly hit the Sport button, engaged 2nd gear and floored it up the hill...but the car didn't move very fast at all and sounded like it was revving high in neutral...the wheels weren't spinning I'm sure and struggling for grip and no DTC light was flashing...evidently I must've not released the clutch properly and when I took stock and tried again the car surged forward. However, I was engulfed by a strong 'burnt clutch' smell so I turned into the next side street and pulled over. Upon investigation, the smell was clearly coming from the rear wheels! The tyres look okay and the smell isn't like burnt rubber anyway - I think - and reminds me more of a clutch smell. Any ideas? Have I damaged something? The car drove normally the rest of the way home and is now tucked away cosily in the garage making lots of cooling noises.

Thanks,
S
 
chances are it was the clutch and the smell just seemed to be coming from the back end. Brakes are the only other suspect.

Take her out and floor the car from standstill at the lights....if she hits 60 MPH in under 5 seconds she's fine! :thumbsup: Seriously these are tough cars and built to take the strain..
 
sammyz said:
chances are it was the clutch and the smell just seemed to be coming from the back end. Brakes are the only other suspect.

Take her out and floor the car from standstill at the lights....if she hits 60 MPH in under 5 seconds she's fine! :thumbsup: Seriously these are tough cars and built to take the strain..

I hope so! :thumbsup: It has only done 4200 miles now so I don't want to have broken it already! The whole front section of the car smells fine but at the rear wheels the discs are hot and the smell seems to emanate from there. Odd.
 
sammyz said:
Could be a rear brake binding. Did one side seem hotter than the other?

No...it was just weird, I have never experienced anything like it. The car revved loudly but didn't go anywhere fast but I was moving. And then the smell. I then released the accelerator, re-engaged the clutch and then released and set off again - and it surged forward rapidly. It was almost like I was riding the clutch which maybe I did slightly by mistake but the smell definitely seems to come from the discs at the back. I wasn't braking at any time and have never had a problem with the brakes. The smell is all but gone in the garage now and the car is cool. I might take it out for a blast up the road later and see if it feels any different.
 
The car can apply the brakes as part of the traction/safety systems so maybe it was a glitch with the 'brain'....as you say take her for a blast and if anything feels wrong get her to the dealers.
 
sammyz said:
The car can apply the brakes as part of the traction/safety systems so maybe it was a glitch with the 'brain'....as you say take her for a blast and if anything feels wrong get her to the dealers.
Aha! Maybe I did something that caused the car to apply the brakes then! It would make sense to me actually. Wonder what I did wrong though? Or if the car's brain is as faulty as mine?? :? :o
 
Likely you slipped the clutch - someone on another board did exactly the same thing and reported the same smell and area of build up around the rear wheels.
 
Caddyshk said:
Likely you slipped the clutch - someone on another board did exactly the same thing and reported the same smell and area of build up around the rear wheels.

Hope my clutch is okay then - wouldn't want to have to replace it anytime soon!

Driving the ///M is different to my previous BMW's - they were a lot more forgiving I think. The ///M demands more attention and effort - which is a part of the attraction for me providing I don't break anything.
 
I noticed you said you floored going UP a hill. I'd have the "Hill start assist" looked at. Basically that holds the car when starting off up a hill by holding the rear brakes on for a few seconds while you let the clutch out to engage the gear. Could have engaged for some reason? :wink:
 
or a combination of the hill assist and the DSC? Got on it so hard the hill assist didn't come fully off before the DSC kicked in? I'd drive her and see if she goes like before. I'd also have a mechanic check her out thoroughly on her next visit. Could you have cooked some of the lubricants in the tranny/diff??
 
From personal experience, it was the clutch cooking. The tranny on the //M will sometimes not fully engage during a fast shift and high rev's in second. Did this at the Drag Strip once :x Your clutch and all related systems are fine, just a little smell to remind you to fully engage the gear before flooring it, next time. :)
 
ovrkll said:
From personal experience, it was the clutch cooking. The tranny on the //M will sometimes not fully engage during a fast shift and high rev's in second. Did this at the Drag Strip once :x Your clutch and all related systems are fine, just a little smell to remind you to fully engage the gear before flooring it, next time. :)

1st and 2nd are tricky that's for sure! I must've made a mistake in the changing of the gears and caused myself some embarrassment in the process; which worries me not a jot as I am only concerned about the health of my little car! I had no such problems this afternoon driving home. I'm thinking that I would probably have been okay if I hadn't used Sport mode as it possibly allowed less room for error on my part.

Cheers everyone for the advice! :D
 
FirstKnight said:
ovrkll said:
From personal experience, it was the clutch cooking. The tranny on the //M will sometimes not fully engage during a fast shift and high rev's in second. Did this at the Drag Strip once :x Your clutch and all related systems are fine, just a little smell to remind you to fully engage the gear before flooring it, next time. :)

1st and 2nd are tricky that's for sure! I must've made a mistake in the changing of the gears and caused myself some embarrassment in the process; which worries me not a jot as I am only concerned about the health of my little car! I had no such problems this afternoon driving home. I'm thinking that I would probably have been okay if I hadn't used Sport mode as it possibly allowed less room for error on my part.

Cheers everyone for the advice! :D
Many of us are convinced there's a syncro problem with second. BMW is monitoring it for sure. A bunch of folks have had the cars into Dealers for this issue - in one instance the transmission was replaced.
 
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