..and to add to that, make sure the rear axle is centered,,,something no one thinks about on swing axle suspensions..

If you need to replace the king pins, you will also need a king pin reamer to properly align the new bushings and size for the new pins. Not an easy tool to find.

The great majority of kingpin changes are a false diagnosis for lower trunnion joint wear..very common mistake.
look real close when you pull up on a bar under the tire at the trunnion and the cross bolt..those are the most suseptical wear items on kingpin suspension b/c it is a threaded bearing surface and they do not last long w/o pleanty of grease.

lots of responses.

I apprecaite the help.

I did grease crap out of the suspension, wheels were off so I cleaned everyone up and went crazy with the grease gun.

With so many worn items, my intention is to eliminate the largest contributor.

I will follow AD's advice on the suspension movement diagnosing, seems like a better method.

I will particularly look at the upper trunions, as one the DS the rear eccentric bushings was missing, had to steal one of a J-yard car.

I replaced the sub frame mounts, and this gave very little result, the lateral stabalizing bar was fine.

The structual foam will be used, to reinforce the welding,

Can't hurt so long as welding is done correctly.

If anyone has a picture of the steering assembly for a V-8 car I'd apprciate it, I have to hope a pick a part has one, to verify what type of idler arm is used.

Right now the idler arm is not the one pictured in the shop diagrams, or what I've seen under 6 cyl cars. It looks like the pitman arm, so I have not worried previously.

Did i mention the price, for best diagnosis/advice?

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Davo

500sl R107

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The trick to greasing these is to juak the car from a body rail rather than a suspension component and then grease it [ Unloaded Suspension]

The reasoning here is b/c with the susp unloaded , the grease gets into the parts that are compressed when you let the car down [ normal suspension], thereby putting the grease where it is needed the most... if you just grease a loaded suspension, the grease simply goes out the other side of the joint and never gets between the wear pieces, so you accomplish nothing in the true sense of lubrication ...........
Same goes for tie rod and idler arms.. you want to move them throughout their movement range as you grease them, so the lube get into all sides of the joints.

Holy CRAP! Fix that before ANYTHING else. All other solutions are guesswork, it's highly likely this is the cause of everything. When you're riding on the bumpstops, the only thing keeping the front from being a solid rock are those "Leaf springs" and if those bushings are at all suspect, forget about ride! Get front springs from a 4.5 engine car. 280SEL springs may not work because there were 280SEL's with 6-cyls.

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Current:
2021 Charger Scat Pack Widebody "Sinabee"
2018 Durango R/T

Previous:
1972 280SE 4.5
2014 Jeep Grand Cherokee Limited "Hefe", 1992 Jeep Cherokee Laredo "Jeepy", 2006 Charger R/T "Hemi"
1999 Chrysler 300M - RIP @ 221k

Yeah this is definitely gunna be fun.

I'll post results as they occur

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Davo

500sl R107

The steeting geometry was altered. The stock idler arm and pitman arm were replaced by, presumably, another mercedes part.

The result is the drag link, sits about 1-1.5' lower then stock, this is also appearent from the washers and bolts used to reposition the end of the steering shock which is mounted to the passenger side body, near the lateral support rod.

So the inside ends of the tie rods no longer lie on axis or parallel to the lower control arm.

This new knowledge is thanks to Dusty, who provided the bump steer link, which explained this very well.

The fix, will be to put the original pitman arm and idler arm back on, pray there is still enough clearence to the pan, relocate the oil filter, and relocate the exhuast as required.

Hah, one problem devined.!!!!

Thanks to Dusty, for his sage insight May the car Gods shine down on your future endeavors, for aiding a fellow!!!

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Davo

500sl R107

1960 - 1964 Corvair's use the similar type of system, except at the opposite end of the car. The Corvair has the engine in the rear and uses swing axle suspension. You move the engine / transmission to set the toe on the rear wheels.

One thing that many people ignore is the proper tyre pressure settings for proper handling. Handling charismatics can be changed drastically by just making a small change that you might think insignificant, such as using wheels of a different offset or size. Sometimes the results are positive, and other times disasterous.... Dusty....