1983 240D 185,900 miles


I should really start following your guys suggestions on this saying "If it aint broken don't fix it". Well, I love working on my car so I'm constantly upgrading some part or another just for the heck of it. Today I decided to tackle the TRANSMISSION MOUNT. I previously did the engine mounts and yesterday I did the engine shock. How hard can the tranny mount be ?

I took the old one off and just let the transmission hang there along with the shaft. Was I supposed to support them ? Anyway, I installed a new one from the dealer so it was definitely OEM. The job was not hard and only took about 45 minutes. I turn the car on and I hear a noise coming right from underneath the tranny. I get under the car and nothing is moving except the exhaust. I put my ear close to the mount and it sounds like the drive drain is vibrating. Not too familair with drive drains since I've yet to tackle a problem dealing in that department.

I figured that it needs to wear in for a few minutes. I begin to drive it and the best way to describe the sound and vibration coming from underneath is "do you know when you swerve off the road and you hit those little grooves on the side of the highway?" That is the exact sound I hear just not as distinct. I have a feeling it's something with the drive shaft being loose. I came home and turned the car off and went back underneath and touched the drive shaft. It seemed fine except all the play I got in it. I can twist it in both directions about half and inch. Is that normal ?

Please help me out as I am stumped.

I really have to stop messing with the car.

__________________
Audi TT

look real close at your flex joints for cracks, etc. Also check the driveshaft support bearing and mount for damage.

__________________
Proud owner of ....
1971 280SE W108
1979 300SD W116
1983 300D W123
1975 Ironhead Sportster chopper
1987 GMC 3/4 ton 4X4 Diesel
1989 Honda Civic (Heavily modified)
---------------------
Section 609 MVAC Certified
---------------------
"He who fights with monsters might take care lest he thereby become a monster. And if you gaze for long into an abyss, the abyss gazes also into you." - Friedrich Nietzsche

i hope it's not driveshaft related..

__________________
Audi TT

Well, its mostly a check everything while you are under it. the rubber mount for the driveshaft support bearing doesn't last forever. You need to look closely at all mounting points, and moving assemblies. Anything with rubber. Maybe the stress seperated something that was about to go anyway.

__________________
Proud owner of ....
1971 280SE W108
1979 300SD W116
1983 300D W123
1975 Ironhead Sportster chopper
1987 GMC 3/4 ton 4X4 Diesel
1989 Honda Civic (Heavily modified)
---------------------
Section 609 MVAC Certified
---------------------
"He who fights with monsters might take care lest he thereby become a monster. And if you gaze for long into an abyss, the abyss gazes also into you." - Friedrich Nietzsche

My guess is you damaged the front flex joint which is not that big a deal. I just don't see the trans being damage unless it somehow was pryed on, that said when I had mine replaced the mechanic used a trans lift to lift and secure the tranny.

__________________
'10 Chrysler T&C Stow-N-Go White. Grandpa's ride.

'13 Chrysler 200 Touring Candy Red. Grandma's ride.

Age and cunning will always over come youth and vigor.

could be TRANS related, that would be worse. You must have used a jack or something to lower/raise the trans. You didn't leave it there supporting it? Did you disconnect the driveshaft or just leave it attached?

Kamil,

I think the only you thing you did wrong was spell Moron incorrectly.

__________________
84 300DT Puke Yellow. Totalled after 438,000
84 300DT Orient Red. 169,000 (actual mileage may vary)
2002 Explorer EB (wife's)

i left the trans connected to the driveshaft while replacing everything. i just let it hang there. i guess I screwed it all up.

__________________
Audi TT

Now see I was going to say that, but thought I would give him a break. I wondered how long before somebody was a smart-ass.

__________________
Keep everything as simple as possible-but no simpler--Albert Einstein

A Moran..??????
Don't you mean moron?

Anyway, the others gave pretty good advice. Just had to jump on that one.

__________________
'85 300SD (formerly california emissions)
'08 Chevy Tahoe
'93 Ducati 900 SS
'79 Kawasaki KZ 650
'86 Kawasaki KX 250
'88 Kawasaki KDX200
'71 Hodaka Ace 100
'72 Triumph T100R

Moran, Jim moran.....the Virginia Democrat who blamed members of a certain religion for the Gulf war????????? ha ha ha , Kamil let us know what you find. I am real curious. You don't have old motor mounts that might have collapsed do you? Just trying to come up with reasonible things to check.

__________________
Proud owner of ....
1971 280SE W108
1979 300SD W116
1983 300D W123
1975 Ironhead Sportster chopper
1987 GMC 3/4 ton 4X4 Diesel
1989 Honda Civic (Heavily modified)
---------------------
Section 609 MVAC Certified
---------------------
"He who fights with monsters might take care lest he thereby become a monster. And if you gaze for long into an abyss, the abyss gazes also into you." - Friedrich Nietzsche

God, I am a Moron. I found the problem. It was nothing you guys guess which surprises me since you guys always get everything right. Well, the U-shaped bracket was upside down. I put the open ends facing down as opposed to facing up. I am a master at removing transmission mounts. I went through 2 mounts thinking it was bad, I put the old one on a few times. I timed myself on the last try and I can remove the trans mount in just under 5 minutes. I must be the world's fastest mercedes trans mount changer. I can get it right this time also.


Thanks you for helping me out. I was getting scared that it might have been the driveshaft. Fortunately, it wasn't.

I'm still hooked on motoring so next week something is getting changed as well. Something easier, much easier; probably just the oil.

__________________
Audi TT

Yeah, I was gonna suggest checking the alignment of the tranny/driveshaft. You can get them a bit sideways sometimes, but no like putting the crossmember on upside down! With that much angle back there, it must have shaken like crazy, to say nothing of the risk of running the fan into the rad!

Couldn't do that on the 280, I don't think you could push hard enough to get it up that far.

Remember that the mount goes inside the crossmember and you won't forget.

It is a good idea to use a jack under the tranny, though. On the W124 and later chassis with the "fragile" flex disk, you could easily damage it when the tranny droops down. Ditto for engine mounts, I suppose.

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

[QUOTE=kamil]God, I am a Moron. I found the problem. It was nothing you guys guess which surprises me since you guys always get everything right. Well, the U-shaped bracket was upside down. I put the open ends facing down as opposed to facing up. I am a master at removing transmission mounts. I went through 2 mounts thinking it was bad, I put the old one on a few times. I timed myself on the last try and I can remove the trans mount in just under 5 minutes. I must be the world's fastest mercedes trans mount changer. I can get it right this time also.


Thanks you for helping me out. I was getting scared that it might have been the driveshaft. Fortunately, it wasn't.

I'm still hooked on motoring so next week something is getting changed as well. Something easier, much easier; probably just the oil. [/QUOTE


U shaped bracket???????? was nothing like that on my W116, but anyway I am glad it was something so simple, and certain you are too.

__________________
Proud owner of ....
1971 280SE W108
1979 300SD W116
1983 300D W123
1975 Ironhead Sportster chopper
1987 GMC 3/4 ton 4X4 Diesel
1989 Honda Civic (Heavily modified)
---------------------
Section 609 MVAC Certified
---------------------
"He who fights with monsters might take care lest he thereby become a monster. And if you gaze for long into an abyss, the abyss gazes also into you." - Friedrich Nietzsche

Praying won't help one bit if you put the drain plug in upside down too.

__________________
Never a dull moment at Berry Hill Farm.