OM606
Member
Hello everyone!
I am trying to get rid of a driveline vibration, i'll try to explain as best as i can what happens but this is really doing my head in. I bought the car about a year ago and swapped the motor mounts and front flex disc as they were decimated (Lemförder mounts, SGF flex discs). Put a set of new Goodyear tyres too. Got a few months of smooth driving out of it. At some point i thought it wasn't driving as smooth as it should and there was some kind of vibration coming from underneat the car or at the back.
Decided to give the car a good inspection and replaced the trans mount with one from Febi and realised that the rubber was collapsed around the the propshaft carrier bearing causing the driveshaft to move about when taking off. About a month ago i've replaced the carrier bearing/bushing with a Febi unit as well as the rear flex disc while everything is apart. Now i have this vibration which is very pronounced around 80-100 kmh (50-60 mph?). It's not a vibration that shakes the car but something that can be felt and heard, like a rumble, sounds kind of like i'm driving with an open window. Extremely annoying.
This whirring vibration is not influenced by cornering and is the same under load or coasting or in neutral, only speed dependent
Observations:
- Both halves of the propshaft are aligned according to factory marks. It was off by one spline which i thought was the cause of the vibration, we took it apart again and put it back together as it should but it did almost nothing.
- All the balancing weights are still welded on the driveshafts.
- Slight play in the splines but none it the u-joint, whiched moved freely if i recall.
- Slight play in the gearbox output bearing.
- No play in the diff pinion bearing.
- Slight play in differential CV axle bearings but not a drop of oil leaking.
- Can't make the CV axles clunk with wheel on or off the ground.
- Front vibration damper in good shape.
- Differential mounts are old but ok, no play at all there.
What i've tried to no avail:
- Rotated and balanced wheels many times, no issues there.
- Unbolted the engine mounts, trans mount, exhaust hanger, carrier and rolled the car back and forth a few time.
- Tried changing the angle of the driveshaft by installing various thicknesses of washers under the carrier.
This is driving me absolutely mad to the point of thinking about getting rid of the car despite all the other work i've done to it. The car is a 97 W202 C250 TD manual, 385000 km on the clock.
I am trying to get rid of a driveline vibration, i'll try to explain as best as i can what happens but this is really doing my head in. I bought the car about a year ago and swapped the motor mounts and front flex disc as they were decimated (Lemförder mounts, SGF flex discs). Put a set of new Goodyear tyres too. Got a few months of smooth driving out of it. At some point i thought it wasn't driving as smooth as it should and there was some kind of vibration coming from underneat the car or at the back.
Decided to give the car a good inspection and replaced the trans mount with one from Febi and realised that the rubber was collapsed around the the propshaft carrier bearing causing the driveshaft to move about when taking off. About a month ago i've replaced the carrier bearing/bushing with a Febi unit as well as the rear flex disc while everything is apart. Now i have this vibration which is very pronounced around 80-100 kmh (50-60 mph?). It's not a vibration that shakes the car but something that can be felt and heard, like a rumble, sounds kind of like i'm driving with an open window. Extremely annoying.
This whirring vibration is not influenced by cornering and is the same under load or coasting or in neutral, only speed dependent
Observations:
- Both halves of the propshaft are aligned according to factory marks. It was off by one spline which i thought was the cause of the vibration, we took it apart again and put it back together as it should but it did almost nothing.
- All the balancing weights are still welded on the driveshafts.
- Slight play in the splines but none it the u-joint, whiched moved freely if i recall.
- Slight play in the gearbox output bearing.
- No play in the diff pinion bearing.
- Slight play in differential CV axle bearings but not a drop of oil leaking.
- Can't make the CV axles clunk with wheel on or off the ground.
- Front vibration damper in good shape.
- Differential mounts are old but ok, no play at all there.
What i've tried to no avail:
- Rotated and balanced wheels many times, no issues there.
- Unbolted the engine mounts, trans mount, exhaust hanger, carrier and rolled the car back and forth a few time.
- Tried changing the angle of the driveshaft by installing various thicknesses of washers under the carrier.
This is driving me absolutely mad to the point of thinking about getting rid of the car despite all the other work i've done to it. The car is a 97 W202 C250 TD manual, 385000 km on the clock.
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I wonder how many vehicle out there are rolling around with the flexdisc in the wrong way around ? Lesson learned , certainly one to keep an eye on . result Rusty 