w126 guide rod install ? with # of threads
 

89 300SE 135k all new suspension and steering compenents, other than the guide rods....
When I put them in. ..If I dont have the exact # of threads as the original install.....like I'm off a turn or so...What will the effect be?
Will the caster/ camber/ ride height/ toe ect... be off?

It also has new H&R springs, upper rubber bushings, and shocks right now but the drivers front sits 1/2" lower than pass side. That happens to be the side the guide rod is real bad also. Pass side is clunky too.
Yes ...alignment to follow this also.

Ken, if I'm not mistaken, the error in the guide rods will allow the LCA to move forward or rearward........depending on the error........and the toe will be affected. This will definitely appear as a pull in the steering, unless both sides are magically off by the same amount. The ride height and camber will not be affected by the error. I'm not positive on the caster.

I sense that you are hoping for the guide rod to fix the ride height error, but, I am doubtful. I struggle with irregular ride heights on two of these. The SDL has new springs and new pads in the rear and the ride height differs by 1/2" from side to side. It's a bit baffling........unless the springs are not equal when under compression. M/B alludes to this possibility in the manual and uses pads of varying thicknesses to compensate for it. I may have to install a thinner pad on one side of the SDL to finally cure it.

Assuming the guide rods are the same as on my 85 380SE, I would've thought that they have a big effect on the castor, since the turning of the rod will move the lower part of the spindle forward/backward?

Yes, this must be true. I was originally thinking that the entire assembly moves forward or backward.......but......the upper arm doesn't move at all. Therefore, the castor must be affected heavily as well.

Thanks for the clarification.

Answer
 

This has direct impact upon Castor, Toe and to some degree Camber = the car must be aligned by a Mercedes qualified technician with the MB wheel spreader bar.


Have a great day.

If I am off on the # of threads, is this something a MB Shop alignment will easily be able to straighten out?
Should I tell them I just did the guide rods & have them check specifically?

Answer
 

Yes.
Any good MB tech with the correct tool will do it right the first time.