When I am at a dead stop and put the car into reverse, or from reverse to drive, I notice a clunking noise when the car changes into the selected gear. Is this normal? I haven't noticed it before, but really haven't listened for it.

It's not terribly loud, but it is distinctive, and definitely and "clunk"

Suggestions, opinions and advice greatly appreciated, as always.

Mermaid.....

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proud owner of 300E

You most probably have a driveshaft coupling going bad. This is the disc between the trans and the driveshaft.

Another posibility is the rubber mounts that hold the rear of the differential to the rear subframe.

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Steve Brotherton
Owner 24 bay BSC
Bosch Master, ASE master L1
26 years MB technician

Steve,
Would this be expensive to fix? Is it something that should be fixed right away? I noticed tonight that it doesn't do it every time?

Mermaid

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proud owner of 300E

Hard to say at a distance. No benefit for the car to delaying the fix. I must say that I have only seen one event where delay caused serious damage. In that case the drive shaft came completely off the transmission (something I have seen more than once). In this particular case the car then continued to drive the shaft which banged around in the tunnel. This does some
expensive damage and is common. What wasn't so common was the fact that on the 300e the SRS crash profile sensor is mounted right above the transmission on the tunnel.

The drivers side airbag blew on him at 50mph. In this case no one was hurt, luckily. Since the cause in this case was a cheap (use it up) customer, the final repair was only moderately more than if it had been done in a timely fashion (he of course didn't fix the airbag system, which would have needed a new sensor and bag about 2 grand). The car just got a little more
"used up".

I don't think there is any immediate concern here. It should be checked out at least at the next service or if vibrations during driving increase.



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Steve Brotherton
Owner 24 bay BSC
Bosch Master, ASE master L1
26 years MB technician

Mermaid,

I had the same problem -- worn driveshaft disk. Cost to replace was about $50.00 plus labor ($60.00).

More an embarrassing nuisance than a real problem.

Eric Silver

Check flex disc first. Check rear diff mounts and if problem still not resolved, probable excessive play in the LB3 clutches from reverse.
Try going from D to R quickly and then do it with a pause in neutral. If more severe doing it quickly, probably LB3 (reverse Clutches).
How many miles on the vehicle? How long does it take for reverse to apply.


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Mercedes-Benz Master Guild - 2 years
Shop Foreman - 20 + years - dealer.
Part owner - MBZ Transmission remanufacture
2000 SL500
1995 E320
1989 300SE

the car has 87,850 miles on it. It's an '89., well maintained and serviced car. I have only had it since 86,000 miles. It doesn't take long to go into reverse when I put it in R, maybe a second? And going from drive to R doesn't seem any different. If I have the and windows closed, I cant hear anything, But if I listen closely I can. My husband says it's more a click than clunk but my friend who has a 95 320E her car doesn't do it at all.

should I just have it checked when I do the 90,000 mile service?

Just have them check the drive line, make sure the flex discs are ok and the center connection is tight. Also have them check rear diff mounts.Good Luck..


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Mercedes-Benz Master Guild - 2 years
Shop Foreman - 20 + years - dealer.
Part owner - MBZ Transmission remanufacture
2000 SL500
1995 E320
1989 300SE

IT MIGHT ALSO BE AN ENGINE MOUNT.
POP YOUR HOOD AND HAVE SOMEONE TAKE A LOOK AN SEE (ALSO HEAR) IF ITS AN ENGINE MOUNT BY THROWING IT IN REVERSE AND DRIVE IN THE PARKING LOT A FEW TIMES.