1982 300sd. when i am approaching 60mph and making a long sweeper right turn, i get a VIOLENT vibration that will not go away until i slow to about 50. if i am doing over 60, there is no issue.

any suggestions on where to look first?

The first thing I'd suspect is really bad alignment and out of balance wheels. Is the treadwear on your tires uneven?

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"spreading a trail of obnoxious where ever we go"
1981 300sd w/ 341,500 miles

http://www.wecrash.com/pics/ddda_banner.gif

it sounds like your tires, if u havent gotten them rotated,balanced and alined,DO IT!
It will make a world of difference!

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82' 300SD

the 300D front end is built like a tank. I cant think of anything analytical thats causing your problem and I know front end problems very very well. Anyway turn your front tires fully out on driver side and passengers side. If you are ambitious, jack the car up. Inspect the ball joint covers and the tie rod covers and all the other rubber joints. Something is definitely loose here and thats all it is. Have someone turn the wheel right to left and i guarentee the problem will be apparent quickly!!!

Sounds like guide rod bushings. Do a search, there's lots of good info.

however whats wierd is it doesnt show up in braking/stops

My 380SE euro had the very same symptoms both times I've had to replace the guide rod bushings. Yes, I've owned it thru two sets so far.
You might want to look at the lower ball joints as well.

i'll swap the rear tires to the front. the rear tires are brand spankin new...as in two weeks old new. then i'll take her for a drive and see if i can produce the problem again. if the problem shows up again, i'll jack up the front end, move things around, and let y'all know what i'm able to find.

the ONLY time the vibration occurs is during a right hand sweeper between 50 and 60mph. no other situation produces this horrible vibration. when it occurs, i feel like steve austin on that runway..."SHE'S BREAKING UP! SHE'S BREAKING UP!"

I notice if I was in a turn at 60-70 mph and hit a small bump in the road it would set off an oscillation in the front end that would shake violently until I slowed or jerked the steering wheel a certian way.
She drove perfect otherwise which was really weird.

well, it turned out to be the old crappy tires allowed to vibrate that badly by the wasted old front shocks. i put all new tires on the car and now i have no vibration. BUT if the car goes over a bump at speed, the front left tire bounces off the ground, as seen by me while driving in another car along side. some bilstein HD's are in order soon.

Bad shocks coupled with out of balance tires will give that problem. That kind of shaking also causes wheel bearings, bushings, and other suspension parts to wear out prematurely.

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RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

13 VW JSW 2.0 TDI 193K, Tuned with DPF and EGR Delete.

91 W124 300D Turbo replaced, Pressure W/G actuator installed. 210K

90 Dodge D250 5.9 Cummins/5 speed. 400K

while you are under there for the shocks, inspect the donuts that hold up the exhaust pipe. as they get weak/cracked, they can let the pipe dangle and bang against stuff too. not to mention what would happen if they let go on the highway!
John

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

Seems like most folks prefer the "comforts" as opposed to the HD's......

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Jimmy L.
'05 Acura TL 6MT
2001 ML430 My Spare

Gone:
'95 E300 188K "Batmobile" Texas Unfriendly Black
'85 300TD 235K "The Wagon" Texas Friendly White
'80 240D 154K "China" Scar engine installed
'81 300TD 240K "Smash"
'80 240D 230K "The Squash"
'81 240D 293K"Scar" Rear ended harder than Elton John