Hello,

Last sunday while on a 200 mile road trip with the TD, I heard, on two occasions, a loud grinding noise which seemed to come from the driveline or axles. It sounded like two metallic parts were grinding together for a second or two, then stopped. Since then, the noise reappears once or twice a day for a second or two. The grinding is so aggressive that the car slows down for those 2 seconds. Does this when at highway speeds only. There is no rumbling noise or vibrations otherwise. Jacked up car and didn't see anything out of place, and wheels rotate freely. Seems to be somewhere in the drive shaft, differential or axles. At this point I'm stumped and just waiting for something to actually break so that I can fix it.

Any ideas???

By the way, I was rear-ended fairly hard not too long ago, with very minor damage to the car, but could this have bumped something out of whack?

__________________
Denis

1979 300TD 189,000 Miles, now running WVO with a home-made 2 tank conversion
1974 230 Gasser 189,000 Miles, For Sale
1961 VW Microbus 162,000 Miles
1961 Ford Fairlane 500, 53,900 original miles
1951 Oliver Super 55 Tractor
2002 Chocolate Lab

This is a potentially serious situation if there is something in the driveline failing which can create enough friction to perceptably slow the vehicle. Catastrophic failure of a driveline component can be fatal....loss of control, parts penetrating the cabin or striking other vehicles, etc.

Check at the pinion gear drive flange for excessive play. Also check the driveshaft center support for excessive movement and rear on the bearing.

__________________
Never a dull moment at Berry Hill Farm.

I changed the left half shaft with one from a parts car and the problem is still there. I also inspected the oil in the diff, no shavings, everything looked fine. The driveshaft u-joints and center support also look OK. I`m thinking rear right wheel bearing at this point, just dosen`t seem silky smooth, like if there was a bit of sand in them.

Are the rear bearings hard to change? Parts car is a 1975 W115, anyone know if the rear hub is compatible with a 79 300TD?

__________________
Denis

1979 300TD 189,000 Miles, now running WVO with a home-made 2 tank conversion
1974 230 Gasser 189,000 Miles, For Sale
1961 VW Microbus 162,000 Miles
1961 Ford Fairlane 500, 53,900 original miles
1951 Oliver Super 55 Tractor
2002 Chocolate Lab

http://catalog.eautopartscatalog.com/mercedesshop/quote.jsp?partner=mercedesshop&year=1979&product=K8020-29480&application=000013580

1979 Mercedes Benz 300TD
Part: Wheel Bearing Kit

K8020-29480 Wheel Bearing Kit $59.27

To answer your question:
The rear wheel bearing R&R is not fun, under the best of conditions.

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1985 300SD
1983 300D
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