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  #1  
Old 04-08-2006, 10:35 AM
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Over-steer??

My wagon feels like it wants to keep turning into a curve, then when I turn out it seems to over-correct the other direction...which results in a kinda see-saw steering wheel action.....small, not a major move, but noticable. She runs straight down the road for the most part, very slight pull to the right, which I think is caused by the road crown. Front end is tight, no loose ball joints and the wheel bearings feel good, steering wheel has about 1" of play. I have tried different driving methods and it seems to prefere a pretty light touch on the wheel.

Now, I know the 300TD is not a sports car and is much heavier than what I normally drive (front wheel drive Chevy Impala that pulls itself through a corner)...but is this "wallowing through the corners" normal? As one post I read said "handles like a coal barge" just the way it is??

Think a new steering damper will help? Thought I'd replace that and have find a good alighnment shop pretty quick.

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  #2  
Old 04-08-2006, 11:07 AM
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Assuming that everything in the suspension is tight, oversteer is caused by the "slip angle" of the rear tires changing faster than the front.

Typical causes are low rear tire pressure, hard rear shocks, hard rear springs, hard rear anti-sway bar (all compared to the front), insufficient toe-in on the front tires, to much weight in the rear, or even different rear tire construction.

But first check the rear suspension and wheel bearings to make sure that something isn't loose.

(edited to correct grevious error)
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  #3  
Old 04-08-2006, 01:59 PM
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I sounds like you are saying the car is leaning hard in the corners. Does the car "bob" or "pogo"after you hit bumps? Blown shocks can cause the car to lean in corners and turning the wheel will just make the car lean.

Have a look at the rear swaybar end links. Also note, if they are worn out, you will hear a rattle from the rear of the car.

These cars will never feel as tight as a new impala in the corners, but it shouldn't feel like a coal barge. The car should remain flat during most reasonable cornering.

I would say it corners like a large car, and the handling is smooth with some rolling, but reasonable speeds should not cause any excessive rolling.

By the way, the impala and the Benz are quite close in weight. The Impala is actually a few pounds heavier than a 300D sedan.
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  #4  
Old 04-08-2006, 02:30 PM
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Bad Steering Damper can cause this.

PART NUMBER SEARCH RESULTS WITH PRICES
Vehicle 1983 Mercedes Benz 300TD Turbo Wagon
Part: Steering Damper
Note:
Product Brand Availability Retail Our Price
M4000-11742 Steering Damper Sachs IN STOCK $32.12

M4000-11742 Steering Damper Boge IN STOCK $29.07

M4000-130225 Steering Damper Bilstein IN STOCK $23.85

http://catalog.eautopartscatalog.com/mercedesshop/sophio/wizard.jsp?partner=mercedesshop&clientid=catalog.mercedesshop&baseurl=http://catalog.peachparts.com/&cookieid=1RS02S9L01RW0UX0M6&year=1983&make=MB&model=300-TDT-001&category=M&part=Steering+Damper





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  #5  
Old 04-08-2006, 02:39 PM
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I had that problem on my sd after I replaced the tie rods. I gave the wheels way too much toe in and it kinda wanted to pull itself into turns.
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  #6  
Old 04-08-2006, 03:22 PM
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Quote:
Originally Posted by Mismost
My wagon feels like it wants to keep turning into a curve, then when I turn out it seems to over-correct the other direction...which results in a kinda see-saw steering wheel action.....small, not a major move, but noticable. She runs straight down the road for the most part, very slight pull to the right, which I think is caused by the road crown. Front end is tight, no loose ball joints and the wheel bearings feel good, steering wheel has about 1" of play. I have tried different driving methods and it seems to prefere a pretty light touch on the wheel.

Now, I know the 300TD is not a sports car and is much heavier than what I normally drive (front wheel drive Chevy Impala that pulls itself through a corner)...but is this "wallowing through the corners" normal? As one post I read said "handles like a coal barge" just the way it is??

Think a new steering damper will help? Thought I'd replace that and have find a good alighnment shop pretty quick.
you don't need to realign after changing the steering shock, but you say it pulls right? Maybe it does need an alignment, but be sure to find a shop that has a locking bar and knows this car. I have seen good reputable tire shops make a car worse after aligning it, they simply need to have the right tool and an experienced alignment technician otherwise its a gamble whether they will make it better or worse!
The test for steering is to disconnect the drag link from the steering box and run the wheels manually left and right to feel for slop or binding then reconnect the link to the steering box. A steering box that has been overly adjusted tight will tend to drag, that is you turn right, then let go of the steering wheel momentarily the car should tend to straighten out. If it stays turning right with no sign of the sttering wheel going back towards center then it may be that the steering box is a relatively new rebuilt one or it may not be adjusted properly. People tend to mis adjust these, its a CCW to tighten and you don't tighten all the way, there is supposed to be slight movement or "slop" to take work off the main working race otherwise the balls wear the race even worse. But there should not be a lot of play in the steering!
A 300TD that has everything aligned to spec and good ball joints, shocks, etc and with a good steering box is a delight to drive and it won't walllow on the road. It should feel fairly precise and responsive (much better though with 15 in wheels and good tires mounted on it!) but this isn't a 124 chassis!
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  #7  
Old 04-08-2006, 03:33 PM
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Quote:
Originally Posted by Matt L
Assuming that everything in the suspension is tight, oversteer is caused by the "slip angle" of the rear tires changing faster than the front.

Typical causes are low rear tire pressure, hard rear shocks, hard rear springs, hard rear anti-sway bar (all compared to the front), insufficient toe-in on the front tires, to much weight in the rear, or even different rear tire construction.

But first check the rear suspension and wheel bearings to make sure that something isn't loose.

(edited to correct grevious error)
I haven't experienced any issues with springs or shocks affecting the wallowing feel on the 300TD steering. The springs were stiffer in pre-82 cars (N/A diesels) and that gives a little more responsive feel to the wagons. I fuond out after converting a NA to a turbo. Another member was replacing the springs in his wagon with springs from an earlier vintage.
The SLS will keep the car level with even a big load in the back and steering doesn't change like it would in a sedan but the feel from the center of gravity and weight will be where it usually isn't and the car will not corner like one without the load.

I doubt the rear sway bar is a factor, unless someone went too a lot of trouble finding a stiffer one for the 123 wagon. If they had the PO would have noted it I'm sure. The description sounds like a worn steering box or possibly it is misadjusted.

If the rear shocks go out they usually leak the hydro fluid all over the ground and the level in the reservoir drops significantly (and the pump will go bad!)
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  #8  
Old 04-08-2006, 06:21 PM
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Once you get the alignment right and the slight right pull eliminated you might have to try a different set of tires on the front. May not apply to 123s but some mercedes gas cars were quite tire sensitive years ago in my experience.
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  #9  
Old 04-08-2006, 08:09 PM
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i vote

for sway bar issues.

tom w
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  #10  
Old 04-08-2006, 08:54 PM
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She's got new shocks, new tires, the rear SLS works great. Maybe "wallow" was a poor choice of words! There is some body sway, not excessive...it'll lean a bit at first, then "harden up"...kinda reminds me of a little sailboat I used to race.

I know part of "the problem" is getting used to rear wheel drive after 10 years of front wheel drive cars....but there is a problem here.

Does the steering damper do just what it says and dampen the steering? Which would in my mind help at least with the over-correcting ( driver error ). I searched a lot threads about dampers....but no one explained how it helped the feel and/or handling...it was just removed/replaced! Well, how did that work for you?
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  #11  
Old 04-08-2006, 10:53 PM
t walgamuth's Avatar
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i suggest

after re reading your post to get someone who has lots of mb experience to drive it and see if it is normal or not.

the handling of a front drive chebby wont be very much like a benz.


tom w
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..I also have a 427 Cobra replica with an aluminum chassis.
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  #12  
Old 04-08-2006, 11:24 PM
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This may sound a little strange but the trailing arm bushings for the rear used to cause a problem similar to this. The inside ones, nearer the driveshaft, were in very bad shape. It was very hard to visually verify this until I dropped the trailing arm for replacement of the bushings. I did notice a little excessive tire wear in the rear.
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  #13  
Old 04-09-2006, 03:55 AM
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The only thing I could think of that's not been mentioned yet is the steering column flex joint that looks like a flex disc, only it's for the steering wheel column before it enters the gearbox. If you turn right, for example, the (presumably worn) disc will have alot of play and the wheels won't react soon, and once they do they will spring to that direction like you describe (overcompensate).
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  #14  
Old 04-09-2006, 04:23 PM
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It is possible

Quote:
Originally Posted by MBeige
The only thing I could think of that's not been mentioned yet is the steering column flex joint that looks like a flex disc, only it's for the steering wheel column before it enters the gearbox. If you turn right, for example, the (presumably worn) disc will have alot of play and the wheels won't react soon, and once they do they will spring to that direction like you describe (overcompensate).
Steering Coupling Replacement
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  #15  
Old 04-10-2006, 10:16 AM
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idle arm bushings

Been there, done that and the idle arm bushings were shot.

It may be a worn trailing arm bushing but, since there's no directional control problems encountered when accelerating or decelerating, I'd be surprised to find them bad. Even a slight amount of wear in a trailing arm bushing will make a 123 feel totally unmanageable when under hard acceleration. Beleive me, you don't want it to be a trailing arm bushing. That job is a gin-yoo-wine PITA!

Idle arm bushings sometimes see premature wear if the cyclone oil separator in the air filter housing is leaking or, if the separator drain is leaking...it drips right onto the bushings.

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