steering? - Page 2 - PeachParts Mercedes-Benz Forum

adamkat22 · #1 12-20-2014, 03:27 PM

just to clarify, you are recommending replacing the entire upper control arm...not the torsion bar? right? also, torsion bar = sway bar?

is there an easy way of aligning the upper control arm and the torsion bar so i can get that bushing/bolt back in? not sure what I'm supposed to force...

Quahog · #2 12-20-2014, 03:33 PM

not necessary to replace upper control arm. I did because it was one of those while-I'm-in-there things.

torsion bar = swaybar

this is not easily replaced w/o removing engine from car, hence the repair sleeve.

Did you just lose the bushing + washer + bolt on the end? threaded area still there?

adamkat22 · #3 12-20-2014, 03:41 PM

carpenter man said

"You can probably buy the torsion arm bushings, washer and bolt separately, but if it was me, I'd go ahead and buy the kit and replace the entire arm. "

i am just trying to confirm which 'kit' and which arm he is talking about replacing...i'm assuming a bushing kit for the torsion bar (although I don't see one at the peach parts store) and replacing the upper control arm...

leathermang · #4 12-22-2014, 11:15 AM

Quote:

Originally Posted by Quahog

.......torsion bar = swaybar ....

Not technically correct.

""The part might be termed a "sway bar" (more properly "anti-sway"), but it is more than that. On most cars, you can remove the sway bar without affecting the basic steering and suspension - i.e. the way the wheels track the road. They are optional to minimize body leaning in turns. Not so on these cars. The sway bar also locates the upper ball joint fwd & aft, so is necessary to align the front wheel. '"--- Bill Grissom

General mechanical knowledge and nomenclature pause....

As Bill mentioned this is a combo unit....
but in the past ' torsion bar' was a NON COILED spring.... usually placed lengthwise with the car... it took the place of coiled springs.... Mid sixties Plymouths were a good example of this... saves a lot of room around the suspension components...

The Mercedes 230 SL also had this.....

https://www.youtube.com/watch?v=UIuo82fubVA

as these are sometimes used interchangeably ... and sometimes not precisely correctly.... thought I would bring up the bigger picture for people to be aware of when reading about suspensions...

Quahog · #5 12-20-2014, 03:22 PM

W123 torsion bar saver

BillGrissom · #6 12-21-2014, 11:23 PM

The "torsion bar saver" costs $120 and requires cutting & welding. Strange to describe that operation as "just ...", especially with the OP having to work in a parking lot. A bolt & washer would be my approach. If you can't find the correct factory part, Ace Hardware might work. If Ace'ing it, I wouldn't fuss trying to find the exact length bolt. I would look for a longer bolt (of correct thread), jam it in tight, then use a nut acting on a big washer to tighten the rubber bushing. You could probably drive that way for years until you have a nice garage and doing the whole suspension. Before that, get the correct bolt & washer at a junkyard. Those rubber bushings fell apart on my 85 300D, making a clunking sound when turning and hitting a bump, with no longer any support from the sway bar (similar to your case). The world didn't end and I drove it a few days until I figured out the problem.

The part might be termed a "sway bar" (more properly "anti-sway"), but it is more than that. On most cars, you can remove the sway bar without affecting the basic steering and suspension - i.e. the way the wheels track the road. They are optional to minimize body leaning in turns. Not so on these cars. The sway bar also locates the upper ball joint fwd & aft, so is necessary to align the front wheel.

Carpenterman · #7 12-22-2014, 12:46 AM

Mr. Grissom, you misread my post. I said "just" replace the upper control arm, not "just" install the repair end.

Look at the OP's first photo. You can see a gap between the barrel of the upper control arm and the lip in the bushing. That's a failed or failing bushing.

Replacing the upper control arm is not a hard job and can be done for less than $100. The only tricky part is separating the ball joint and even that's no big deal if you have the tools. And even if you don't have the tools, all you have to do is lift the other wheel to put upwards force on the sway bar, loosen the ball joint nut a few turns, and tap on both sides of the fitting at the same time, and it should separate.

charmalu · #8 12-22-2014, 10:40 AM

Here is a link to the pelican parts catalog.

1982 Mercedes-Benz 300D Base Sedan - Suspension, Shocks & Springs - Page 2

A DIY Link on the upper Control Arm:

PeachPartsWiki: Upper Ball Joint Replacement

Charlie

leathermang · #9 12-22-2014, 12:36 PM

In this case it is a combo unit... I was just addressing the blanket definition of ' antiswaybar Equaling torsion bar'... without including further qualification....

BillGrissom · #10 12-22-2014, 04:03 PM

Carpenterman,

Sorry I misread. If the UCA is worn, for sure replace it. I recall seeing them fairly inexpensive, with ball joint already installed. I recall little trouble removing the upper ball joint stud with a pickle fork when I removed my spindle (to replace lower ball joint).

"Torsion Bar" usually refers to the main spring in a car's suspension, when of that design - 50-80's Chryslers, Porsches, some pickups. Usually, the bar is straight and only twists. However, Chrysler's 1977-83 F,M,J bodies (Aspen, Volare, ...) had a bent T-bar. They have a loading bolt, which allows easy road height adjustment and easy unloading for removal. Some hood and trunk springs are also "torsion rod springs" (60-70 Darts, Valiants). One advantage of T-bars is that the suspension weight is kept lower. Coil springs actually act as a "coiled torsion bar". The coils don't bend. The rod twists as the spring is compressed, to give the springiness. A disadvantage is that there is also a shearing load, so must be a bit thicker. There must be a strong structure (i.e. heavy) up high to support the spring. If T-bars are superior, seems strange that some Mopar owners weld in an after-market coil-over conversion kit (>$3K).

leathermang · #11 12-22-2014, 07:18 PM

Quote:

Originally Posted by BillGrissom

..... There must be a strong structure (i.e. heavy) up high to support the spring. If T-bars are superior, seems strange that some Mopar owners weld in an after-market coil-over conversion kit (>$3K).

That strong structure also incorporates an adjustment mechanism... So if time and corrosion have take their toll.. then it would be hard to repair that mechanism..... and it was important that the height be adjusted to level ... I think they factory spec required one quarter of an inch or less difference side to side.. and if it was not it gave a wavy ride not found on coil spring cars.. which of course did not have adjustments available at all... so many bit the dust due to mechanics not knowing how to keep them adjusted properly...
Only you and I would think of those torsion bars used on the hoods of those cars.... lol

leathermang · #12 12-24-2014, 06:27 PM

Quote:

Originally Posted by BillGrissom

..... If T-bars are superior, seems strange that some Mopar owners weld in an after-market coil-over conversion kit (>$3K).

https://www.youtube.com/watch?v=UIuo82fubVA

At One minute thirty seven seconds of that video... you can see the advantage of a torsion bar suspension at the rear....
that extreme travel would not be possible with coil or leaf springs.... look at how level the body is... with the travel of the rear wheels so extreme...

vstech · #13 12-26-2014, 10:34 AM

Quote:

Originally Posted by leathermang

https://www.youtube.com/watch?v=UIuo82fubVA

At One minute thirty seven seconds of that video... you can see the advantage of a torsion bar suspension at the rear....
that extreme travel would not be possible with coil or leaf springs.... look at how level the body is... with the travel of the rear wheels so extreme...

um... that car has coil springs...

it does have a torsion antisway bar...

leathermang · #14 12-26-2014, 11:10 AM

Quote:

Originally Posted by vstech

um... that car has coil springs...

I thought I saw an exploded view lately using mopar style longitudinal torsion bars at the rear in combo with that transverse coil spring.... maybe I was dreaming...

Looks like they got that extreme range of movement with the coil springs placed near the center line of the car... so they do not bottom out like ours do way before that much movement...

vstech · #15 12-26-2014, 11:42 AM

Quote:

Originally Posted by leathermang

I thought I saw an exploded view lately using mopar style longitudinal torsion bars at the rear in combo with that transverse coil spring.... maybe I was dreaming...

Looks like they got that extreme range of movement with the coil springs placed near the center line of the car... so they do not bottom out like ours do way before that much movement...

yeah, looking at the suspension of that car, I'm amazed. it's a split solid axle car with a center pivot, and spring... and coil springs at the wheels...