noise when slowing

[SollyD]

i just bought a 01 330ci and when i slow down i get this deep tone humping noise. its hard to explain what it sounds like but its like a wahhhhhhhhhhhh. i dont think its the brakes cause it does it even when i dont hit them. any one got any idea what it can be

[KillFox]

um, does it do it when you turn? or is it just a general kind of thing?

[SollyD]

just when i am going slow. when i am accelerating from a stop and when i come down to a stop it does it. just as like 15mph and under

[Gargoyle69]

There was a post on this a few weeks ago and the collective thinking was that the sound could be the wheel bearings. Might be something to look into.

[nobodeuno]

Some tires will get louder as you slow and apply the brakes, just by design.

[EXtech]

Sounds like your tires are worn un-evenly. I used to see that allllll the time. You should generally rotate your tires every 6-8k miles or so depending on your driving. Sounds to me like the previous owner either never rotated them or very rarely. The dealership may have rotated them before you bought the car, then again maybe not. The other thing that affects tire wear is the alignment. Again, this should be done ever so often (optimum is every 15-17k) to avoid excessive wear and uneven wear patterns. I would rotate the tires and have the alignment checked. Take it back to the dealership and have them do that (they shouldn't charge you as a courtesy).
Without hearing your exact noise, it's hard to say for 100% certainty that the tires are creating that noise. The other posibility is a wheel bearing as previously mentioned. However, usually when wheel bearings are bad or beginning to fail you will hear it constantly while driving.
Just have those two things addressed and you should be fine and noise free.

[peterkulesza]

extech rules. this 's gotta be tires. try getting them on a wheel balancing machine, spin at slow speed and apply a pieve of chalk to the inner and outer surface. it should smear evenly, but i bet yours will chipper and show feathering.

peter

[dado]

I got 2003 325I. Since i got it i hear noise in transmission while i was slowing down. Noise was in sports mode and steptronic. There was a thumping when i was stopping too. I took my car to a dealer 7 times and they finally decided to change my transmission after 5000 miles on it.. I took my car in the morning at 8 AM and they called me at 11 AM and said it's done. I went to a different dealership and asked how long does it take to change transmission, and they told me it takes about 8 to 9 h all together. Now i have 12,000 miles and noise is still there. Service says it's normal. I think they did not even change it.
Do you hear something like a whining sound?

[KillFox]

there are over 300 bolts in the tranny alone. I highly doubt they finished in 3 hours