going deaf!!! help - United Bimmer Community

**mzbmw325i** · 07-05-2007, 03:04 PM

yesterday i removed my OEM muffler to inpsect for any leaks/cracks and trying to pinpoint an ongoing noise while driving the car. it looked fine no cracks or holes in it.

still when i drive the car over 60 the noise level inside the car is unbearable. i am thinking maybe the differential is dying or what should i be looking at. if the exhaust manifold is out how can i tell?

any help is greatly appreciated.

**c1apton** · 07-05-2007, 03:14 PM

this is tough to diagnose without actually hearing it but: (harmonics are tough to narrow down)

A) just because muffler looks good doesn't nessesarily mean the baffles inside aren't blown out. (you would normally notice that in all RPMS)
B) Could be wheel bearings not diff
C) Could be fan clutch
D) Could be trans
E) Could be center bearing (driveshaft)

When was last full maintence? If you're not sure or lack the tools - have a reliable tech, BMW dealer or local shop that you trust have a look at it.

**elsabor67** · 07-05-2007, 03:54 PM

What kind of noise is it? Scraping, rubbing, deep muffled sound? Could be any of the things C1 stated. Take a good look under and see if something looks out of the ordinary (leaks, grease, etc.).

**mzbmw325i** · 07-05-2007, 05:50 PM

Quote:

Originally Posted by c1apton

this is tough to diagnose without actually hearing it but: (harmonics are tough to narrow down)

A) just because muffler looks good doesn't nessesarily mean the baffles inside aren't blown out. (you would normally notice that in all RPMS)
B) Could be wheel bearings not diff
C) Could be fan clutch
D) Could be trans
E) Could be center bearing (driveshaft)

When was last full maintence? If you're not sure or lack the tools - have a reliable tech, BMW dealer or local shop that you trust have a look at it.

A+B) i know my rear bearings are out, but there is this exhaust roaring type sound that even makes the muffler mute, it seems like i have a broken pipe, or the noise u hear on a plane sitting near the wings.

C) fan clutch was replaced last summer

D)my car is automatic, what would make it sound like that.

E)i am planning to replace the flex disc and center bearing..but such noise from a bearing... is it possible?

**Jami318is** · 07-08-2007, 02:08 AM

I have an aggravating noise as well. It reminds me of a set of tires I had on a truck one time. I have no idea if it is the tires but it does sound just like it but maybe a tad quieter. Driving me CrAzY.

**MCBEAMER** · 07-20-2008, 09:05 AM

Issue#1:Sorry to jump on board with another question, instead of helping to resolve one... I too have a roaring issue coming that seems to be coming from the back half of my 97 328is... My noise is speed related as I speed up the noise increases and as another post indicated it sounds like a flat spot on a tire... At this point I have only visually inspected the tires to check for bald spots or broken cords... I plan this afternoon to lift the car and do a better inspection... any idea how to check bearings without major disassembly?

Issue #2: I noticed yesterday when driving that the engine has developed a surge... going steadly down the road at approx 2k rpm's the engine with increase lightly(up & down)... When beginning to pull out the engine is sputtering and seems hesitant... still has power after low idle but the issue is still detectable....

Thanks for any leads to make my afternoon more productive... Thanks in advance and I really appreciate this forum and the help it give us hands on BMW owners...

M