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KurtM
03-22-2004, 05:03 PM
today. More noticable from a dead stop. I am going to inspect after work today and wanted to find out all I should look for.
1) Engine mounts (visual inspection looked fine 1 month ago)
2) Transmission mounts (same as engine)
3) Flex disk (same as above)

any other suggestions would be appreciated.

Thank you
Kurt
95 525ia

Jr ///M5
03-22-2004, 07:10 PM
About how many miles do you have on the 525? I would suspect a worn center bearing on the driveshaft. Can you feel the vibration more in the seat of your pants or through the steering wheel? If it seems to be coming through the seat of your pants, this would indicate driveline problems. Does it go away after you reach a certain speed? I would give the drive-line a good look, but it's going to be hard to check the center bearing condition unless you drop the exhaust. Can you tell exactly where the vibration is coming from, and how pronounced it is? Let us know all the information you can....

Jr

KurtM
03-22-2004, 07:41 PM
since it is more noticable from a dead stop. It does vibrate some upon accelaration but not bad. When I backed into the driveway tonite it also did the same. How long is the center bearing and flex disk supposed to last? Records indicate Flex was changed at 108k, car now has 157k.

Thanks
Kurt

KurtM
03-22-2004, 08:35 PM
and it looks fine, no visable cracks. Motor mounts seem solid and look fine.

What next???

Should I order Center bearing and replace this weekend?
and replace flex disk of course.

If center bearing bad, is it ok to drive? Wifey drives 3 miles to work and I'd get the gas guzzler truck. Mine is 60 mile roundtrip.

Kurt

Jr ///M5
03-22-2004, 09:03 PM
Can you get a look at the center bearing with a mirror and flashlight from the front of the heat shield? The driveshaft should be fairly centered in the bearing. It should start making noise if the rubber around the bearing is shot, causing the shaft to vibrate on take off, but centering itself somewhat under speed.
Remanufactured drivelines from places like Portland Driveline Services run somewhere around $350. If your u-joints are shot (makes a clunk sound when putting it in drive) that is your only option, the joints aren't serviceable. At 157k miles.....hmmm, it's your call. I would keep it close to home until you can get a better look at it. It's the same amount of work to replace the center bearing if not more, than replacing the driveline. But remember that a lot of good money has been spent tracing shimmys and vibrations to no avail. Be thorough with your investigation, it can save you money.

Jr

KurtM
03-22-2004, 09:26 PM
Drove home with radio off and did not hear any clunks, clanks, only the vibration and not at every stop. (6 stop signs and 60 mph drive). I looked using a dentist mirror and flashlight and everything looked fine also. U-joints make no noise when shifting from park into gear. Nothing seems out of the ordinary except for the vibration.

Kurt

shield17
03-22-2004, 10:47 PM
Kurt,

I also have this problem. Dealer told me I need a new drive shaft. Well today it was replaced, Flex disk and Center bearing included. I still have a "shudder" at about 10/MPH and then it goes away. Much better than it was before the shaft replacement. SO back to the drawing board. I will keep you posted as to what I find. Any one else with ideas?

steven
03-22-2004, 11:19 PM
i'm in the same boat except i don't feel anything on takeoff. instead, mine comes at about 55-65 then it goes away. i just replaced the thrust arms/bushings as i had the dreaded shake on braking. that went away so i went for an alignment and it's still there. no noise, just shake....

i got new tires about 3 months ago so i'm going in to get them rebalanced although since i feel the shake in the seat, i think i'm chasing ghosts.

let us know what you find!

thanks

Muratti
03-23-2004, 01:34 AM
at 40 km/hour until 55-60 and dissapears. It is more when the car is cold and gets better when it is warm. Tires balanced, camber / caster has been checked and alignment is perfect. No noise when shifting from P to D. I will check my flex disc, u joint and center bearing this week. I will keep you posted. One moire thing, when releasing the accleration pedal go at 60-70 miles, I can hear strange noise coming from under the car. It is typical driveshaft problem... We'll see the bill and reason...

KurtM
03-23-2004, 10:52 AM
I don't want to replace the driveshaft if not needed. Jr said since there is 157k it's about the same amount of work to replace driveshaft as is center bearing. Not sure if I should just order the driveshaft and replace also.
Any additional input would be appreciated.
Going to order center bearing and flex disk today and install this weekend. Also going to change trans mounts while in there.

Jr, I appreciate your input. Thank you

Kurt
95 525ia w/the shakes

Hector
03-23-2004, 11:52 AM
do they really look good? Sometimes bad mounts can "fly" under the radar upon visual inspection. Should scrutnize them more carefully. Keep in mind that obtaining a re-manufactured driveshaft is not going to be perfectly balanced. I been down this road before and went through the hassle to return a re-manufactured one and purchased a new one. Could feel the improvement. If what has been suggested in the replies to your thread do not work out, then either the driveshaft needs to be re-aligned or you might have excessive runout at the flanges. HTW.


today. More noticable from a dead stop. I am going to inspect after work today and wanted to find out all I should look for.
1) Engine mounts (visual inspection looked fine 1 month ago)
2) Transmission mounts (same as engine)
3) Flex disk (same as above)

any other suggestions would be appreciated.

Thank you
Kurt
95 525ia