Front suspension issues...REPAIRED!
 

What is the weakest part of the front suspension on the w123?

I noticed some really bad inner tire wear. I am going to crawl under it and see what else I can find, with a pry bar. There is no play when I grab the front wheels top to bottom or side to side.

On an old Pontiac I had, the wear parts were the lower ball joints (Luckily these were bolt in vs. press in.) and the upper a-frame bushings.

I know I need to replace the UCA bushing on my 300D, and when I had it raised up the other night, I could see the bolt that runs through it.

Thanks!

Sagging UCA bushings will cause that. The UCA moves inward and causes negative camber.

Ok, cool. By being able to see the bolt, I figured the UCA bushings were shot. I was just wondering what all typically wears out first.

I would second that motion. I just did the UCA last week. And easy DIY.

Now if I could just make the center bearing job as easy......

I can do the UCA in about 10 minutes flat including jacking the car and removing the wheel. Jack the car up so BOTH wheels are in the air that way the sway bar isn't loaded, ubolt the sway bar bushings first, unbolt and remove arm from spindle (use pickle fork and a medium sledge, 5 decent whacks and it should let go), unbolt arm from body, remove and throw at the next door neighbors dog that never stops barking, insert new control arm bolt to car (leave hand tight for now), Here's the golden trick, ok... you ready for it? Use your pickle fork (or any long pipe) and jam it under the sway bar and into the body opening (where control bolts to, you'll see what i mean when you're in there) and pry upwards (doesn't require insane torque, if you are not a 100lb woman you can do it easily) to retighten sway bar bushings as you hold the sway bar up. and finally pry upwards again to fit the ball joint in the spindle. EASY CHEESY!!!

I wish read this before I did one UCA on my car. It took me 4 hours to do, I removed the air cleaner, battery and tray to remove and replace the upper bolt. I couldn't get the ball joint into the spindle all the way, there is 1mm gap left. I think I'll remove the nut holding the spindle with the wheels on to unload the rollbar and put it on again. Sounds right?

Yeah! Thanks for the write up OlBrenner!

Derburger, check to see if there is any play. That 1mm gap could be from "Just barely in spec" machining of the ball joint stud.

Many thanks the JimmyL for his help and taking pictures of the UCA replacement job. We are working on a write up w/pictures and will add it to this tread. The job was not bad, but it was not "easy cheesy" for us. We did the steps as outlined by Ol Brenner, but had to do some tweaking.

UCA replacement. Not as "Easy Cheesy" and not done in ten minutes, by us anyway.
{Ralph's comments and write up is in black. I will add very little in blue. JL}

Items needed: 3/8 drive ratchet wrench and extensions, 1/2 drive breaker bar, 17mm socket, 17mm box wrench and two 19mm sockets, one 1/2" drive and the other 3/8", Jack and jack stands, 3 lb sledge hammer, a pickle fork, and some twine or wire.

Note: Remove and install UCA's one side at a time.
{If you are like us you will need to refer to the other side to see direction of spacers, etc....}

Step one: Safely raise up the car. and remove the wheels. Start UCA removal from the driver's side.

http://i29.photobucket.com/albums/c2...rgrassi004.jpg

http://i29.photobucket.com/albums/c2...rgrassi003.jpg

http://i29.photobucket.com/albums/c2...rgrassi005.jpg


Step two: Marvel at how bad the UCA bushings look while still in the car.

http://i29.photobucket.com/albums/c2...rgrassi002.jpg

http://i29.photobucket.com/albums/c2...rgrassi001.jpg


Step three: Remove the sway bar bolt (Shock tends to be in the way so use the 17mm socket and 3" extension to loosen, then use the box wrench to remove the bolt), remove one of the sway bar bushings.

Step four: Remove the upper ball joint bolt. At this position the jack under the LCA.

Step five: Using the sledge and the pickle fork, separate the upper ball joint from the steeing knuckle. Use the twine or wire to loosely hold the steering knuckle to the shock.

http://i29.photobucket.com/albums/c2...rgrassi006.jpg


Step six: Using the 19 mm sockets, remove the UCA bolt. Remove the UCA and the inner sway bar bushing. Again, marvel as pieces of the bushing fall out and go every where.

http://i29.photobucket.com/albums/c2...rgrassi008.jpg

http://i29.photobucket.com/albums/c2...rgrassi012.jpg

http://i29.photobucket.com/albums/c2...rgrassi007.jpg


__________________

{Ralph's comments and write up is in black. I will add very little in blue. JL}


Take pictures of old and new bushings, look at how the UCA rubbed the body of the car.

http://i29.photobucket.com/albums/c2...rgrassi013.jpg

http://i29.photobucket.com/albums/c2...rgrassi009.jpg

http://i29.photobucket.com/albums/c2...rgrassi010.jpg



Step seven: Install new inner sway bar bushing. Position new UCA into place, hold your tongue and leg just right, and have a helper move the UCA to get the UCA bolt to go back into place, hand tighten the assembly.

http://i29.photobucket.com/albums/c2...rgrassi011.jpg


Step eight: If the new sway bar bushing prevent you from staring the bolt, and you see that the shock is in the way...DO NOT REMOVE THE SHOCK BOLTS!!! We did and almost had a disaster {This cannot be stressed enough. Had the rotor not wedged on the side of the floor jack we might have had the coil spring blast out of its location!!} :eek:...instead, use one of the sway bar bushing washers and thread the bolt to lightly squeeze the bushings into place, then remove the bolt, add the proper bushing washers in place {2 outer} and then hand tighten. Tighten the UCA bolts.

Step nine: Using the pickle fork pry up the UCA and position the steering knuckle so the ball joint spindle goes into the knuckle. Tighten the UCA nut.

http://i29.photobucket.com/albums/c2...rgrassi017.jpg


Step ten: Repeat steps two through nine for the other side. NOTE: The passenger side is much easier with the air cleaner removed.

http://i29.photobucket.com/albums/c2...rgrassi018.jpg


Step eleven: Attach wheels and then lower the car. Tighten the sway bar bushing bolts.

Note: Remember to final tighten the wheel lugs!!! {We might have left this step out....:o}

Take car for a test drive.

Also make sure to thank your helper for the work they did and the pictures they took, and for not laughing at you when you can't find the ratchet or wrench that you just placed by your foot...many times during the job. {He never saw me laugh}:D

{After job is finished and you take your buddy to pick up his orient-named car having windows tinted, open trunk, step back, and remember what exclusive club you belong to......}

http://i29.photobucket.com/albums/c2...rassi019-1.jpg

I call foul on the above statement. Might want to reign in that braggadocio......;);)

One thing I will add to this thread. I heartily recommend getting together with a forum buddy or two to work on your vehicles. It is a great time to shoot the breeze, to check out other examples or these cars, to learn from others, to kick each other in the nuts when we mess up {metaphorically of course}, and just generally enjoy this thing we like to do with a buddy {or buddette}.
And, you might even make it home with some excellent coffee and a few parts. {as an aside, we were musing about the differences with age. Now our deals with baggies include coffee rather than...........:smoking:}
We need a good N. Texas GTG soon. Maybe after Dan and Tab have their :bow:

Amen there Jimmy! Thanks for posting the pics and commentary. It also is a great way to see who has F3 tornado type garage (me) and everything in it's place garage (Jimmy).

Also here is an update to the thread. I bought two new Pirelli 3000 tires for the front. Since replacing the UCA's and adding new tires, my MB drives down the road, with no pulling and sensative, precise steering, like our VW.

OK dumb question.... if the UCA/ball joint effects the inside of the tire, what happens when the lower ball joint goes bad?

It wears the inner part of the road surface???? :wink3:
:D