Once in a while when I back out of the driveway and pull forward I get a brief slight thumping and an slight unstable feeling which quickly goes away as the Car is straightened out.

Even less often it happens when I pull away from a curb.

Does not thump or feel different during cornering or when going over bumps or changing speed or gears.

When I get around to it I will do the checks in the below thread that some members posted.

In the mean time I would be interested in comments on symptoms of people who have had the worn trailing arm bushings.

Note that I have replaced the front Control Arm Bushings long time ago (totally rotted out) and I actually have the Bushings for the rear trailing arms but typically I don't know where I put them other then they are in a box with other Mercedes Parts that I previously bought.

http://www.peachparts.com/shopforum/diesel-discussion/111052-trailing-arm-bushing-w126-1985-300sd-diy.html

“Jack the wheel free of the ground and apply torque via a lug bolt with the parking brake set. If the wheel moves back and forth, bushings are shot. If not, check to see if the sway bar links are still present, if not, replace.”
In anther post.
“A twenty inch pry bar between body and trailing arm/bushing area gave me 4mm trailing arm movement
Close examination of bushing shows the rubber coming out one side.
The outside bushings on both sides are very bad.’

http://www.peachparts.com/shopforum/diesel-discussion/136824-thudthudthudthud-sound.html#post1010405

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84 300D, 82 Volvo 244Gl Diesel

I just recently replaced mine and the difference was noticeable. I was experiencing a slight shift to the rear end of the car. When cornering it would swing ever so slightly further outside of the corner (like an exaggeration of the way the car naturally sits into hard cornering with good suspension.) When traveling in a straight line at speed, switching from acceleration to deceleration and back (engine braking only) there was a slight shift of the rear end as well. Nothing crazy, but noticeable if you’re in tune with your car.

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'83 300D turbo diesel (334k daily commuter)
SOLD '80 240D 4 speed manual, #2 piston pitted from crushing a 10mm nut. Running it 'till it burns through.
'78 F-150 300cid 4spd od (with my great unkle's original sales receipt)
SOLD '66 Ford P-350 delivery truck (almost driveable)
'49 Dodge B1D (1 ton Pilothouse era truck) not running but all there, candidate for om617 and 4x4 conversion when money permits.

I have had the Car back from my Wife for about 3 weeks. My Wife never notices anything till something stops working. I don't know if I am in-tune with the car but I get in and I notce stuff.

I replaced the linkage support on the fire wall because the accelerator pedal was acting funny and that fixed that.

I thought the issue I described might have been my brakes binding in the rear and found the pads were badly worn but not to the metal. I replaced the pads and the described symptoms went away for 3 days till today.

Spent a hour looking for that Box of Car Parts while re-arranging my stuff. I am 1/2 way moved out of this House and into another. There is a small chance the box of parts is at the other house.

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84 300D, 82 Volvo 244Gl Diesel

You might also want to check the cv joints on the axles. Based on your description of the problem and a night’s sleep, I’d suspect them before trailing arm bushings. I think if the trailing arm bushings were bad enough to cause the issues you’re having they would be very noticeable in cornering and switching from accel to decel.

Also, it’s a bit of a project to do those bushings. Not terribly advanced, just a lot of road dirt, grunting and hard work with multiple jacks and very tight bolts. Sounds like a good idea to do that prybar check before just replacing them.

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'83 300D turbo diesel (334k daily commuter)
SOLD '80 240D 4 speed manual, #2 piston pitted from crushing a 10mm nut. Running it 'till it burns through.
'78 F-150 300cid 4spd od (with my great unkle's original sales receipt)
SOLD '66 Ford P-350 delivery truck (almost driveable)
'49 Dodge B1D (1 ton Pilothouse era truck) not running but all there, candidate for om617 and 4x4 conversion when money permits.

Actually it is very surprising how bad sway bar links will make the rear feel loose. I'd go there first. They're very inexpensive too...and easy to change.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

I will check that when I check the other stuff.

I have found 2 boxes that have some Mercedes Parts in them but neither the rear control arm bushings.

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84 300D, 82 Volvo 244Gl Diesel

Badly worn bushings create rear steer problems. Where the rear wheels move around independently enough it impacts the steering.


Usually quite noticeable with many cars I have owned when it is present. The common test has been descried by another poster. On and off the accelerator pedal makes a noticeable difference when they are badly worn. You almost cannot miss the effect.

Having looked in every possible place at my Long Beach House and not finding the Bushings I at the same time filled 4 of those large plastic storage containers with stuff to take to my other House.

Sure enough they were at my other House.

Everyone is going to howl but the bushings are part of a front end kit I purchased around July 2008 that turned out to be all URO parts (the same kit seems to be $320 now). Since it was a front end kit I did not expect it to come with the Rear Trailing Arm Bushings nor the plastic Sway Bar Links but it did come with them.

In the below thread I used the URO lower Control Arm Bushings and the Upper Control Arms that came in the Kit. I did not use the URO lower Ball Joints. With the exception of the Boots on the Upper Control arms the URO Lower Control Arm Bushings and the rest of the Upper Control arms are fine after 10 year of use. But, I doubt if it gets driver more then 5,000 miles per year.

So since I bought them and have them I am going to use the URO rear Trailing Arm Bushings.

Here is my front lower control arm thread: Unexpected trouble removing front Lower Control Arm Bushings.

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84 300D, 82 Volvo 244Gl Diesel

Well I jacked the driverside rear up and removed the Tire and that exposed a small portion of the rear trailing arm bushing area. I pried and got about 1/8" of up and down movement and while not for sure it looks as if the inner tube of the Bushing is no longer bonded to the rubber.

That is without removing anything but the Wheel.

Even though in the past I changed out a damaged rear trailing arm I cannot remember the deatails like where I put the jack.

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84 300D, 82 Volvo 244Gl Diesel

jacked up with the tire still on you'll get better leverage for checking up/down, side/side play.

If you can't get someone to help for watching the bushing play, set up the camera on your phone to record it. Then you'll have the evidence.

Mine were so bad it made the steering terrible, unpredictable, especially at higher speeds and windy conditions .
Fixed everything in the front before finding out it was the rear causing most of the problem. I removed the whole rear axle with the subframe and did the forward bushings as well while at it.



I used thick rebar (sleeved with some thin tubing); supported the rear of the car with the rebars

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1985 300TD 1981 Scirocco 1.6D conv 1986 Golf 1.6D 2003 Golf TDI

What I found.

Some of the Trailing Arm Bushings showed separation and play between the inner tube and the rubber and the tube is supposed to be bonded to the rubber. See pic.

When I lowered the Subframe on the passenger side the subframe bushing fell out. see pic.

So I had 2 sets of problems, Trailing Arm Bushings and Subframe Busings. The Trailing Arm Bushing are installed because I already had new ones but I am waiting to receive the Subframe Bushing.

Attached Thumbnails

   

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84 300D, 82 Volvo 244Gl Diesel