Newbie Question: Upper Control Arm Replacement - PeachParts Mercedes-Benz Forum

digieditny · #1 10-12-2010, 06:41 PM

Ok so I got the driver's side upper control arm in the mail today. My mechanic is going to charge me $220 to install it. I was wondering how REALISTIC is it to try to do it myself. I have absolutely no experience doing any major auto repairs. All I have done is change my fuel filters and my air filter mounts. I have read a lot of material and it seems doable but I'm afraid of running into any major problems. The installation would need to be done in 1 day because I have to move my car from opposite sides of street parking since the city cleans them every day.

I have the money to pay the mechanic but working on the car myself will be much more rewarding. Plus... I could put the money towards buying more tools.

What do you think? Say if you were new at working on cars. Would you do it? How much experience did you have when you installed your first upper control arm?

digi

tangofox007 · #2 10-12-2010, 07:09 PM

Quote:

Originally Posted by digieditny

How much experience did you have when you installed your first upper control arm?

I am dumber than a box of rocks and I can replace an upper control arm. And, without complications, I can do it in 20 minutes.

KenB · #3 10-12-2010, 07:14 PM

It's pretty doable but I hate working with such pressure (like I gotta move my car by morning or get a ticket) when I'm new at something. I could see a novice getting hung up on getting a ball joint loose or something (just beat the crap out of it with a sledge hammer) or not know what to do because the ball joint stud keeps spinning and won't let them tighten down the nut all the way.

Yeah, you could do it but is there anyone experienced who could supervise you? In any case $220 sounds like a hell of a lot of money to install an upper control arm. I think I'm in the wrong line of work...

Ken

Yak · #4 10-12-2010, 07:20 PM

Working on the street in any case is iffy, unless it's a quiet residential street. The driver's side makes it a bit worse unless you park against the flow of traffic in order to put that side near the curb. No big deal in some places, a nice quick ticket in others.

One of the nice things about the UCA repair is that you can get pretty easy access to everything and sort of prep the job before fully committing: can you loosen the nut/bolt holding it in, can you loosen the bolt on the torsion bar, can you loosen the nut on the ball joint?

If they're stuck, then maybe it's time to pay someone else or wait for another day. There's a long precautionary thread about a bolt fused to the sleeve inside the rubber bushing. I think that one's the exception to the 'not-too-difficult' rule.

toomany MBZ · #5 10-12-2010, 07:25 PM

There is a bunch of info on the subject as you (OP) state.

Lower the car onto the lower control arm.

The problems come when you have difficulty removing the top bolt or dislodging the ball joint. Read up on those two items.

Most new ball joints come with an allen socket in the end, use the proper size wrench and simply hold it till you get the proper torque.

The manual says to use a certain size piece of metal, I found an open end wrench fits well. Page four.

No need to disturb the shock or spring.

Yak · #6 10-12-2010, 07:27 PM

Precautionary tale, but don't let it scare you. Mine came right out, which I think is the norm.

http://www.peachparts.com/shopforum/showthread.php?t=249774&highlight=UCA+rubber+torch&page=2

Post #25 has the summary version.

ImBroke · #7 10-12-2010, 08:42 PM

Mine came out easily as well. No problems.

vstech · #8 10-12-2010, 08:47 PM

loosen the nut on the ball joint, and whack the side of the spindle it passes through. the joint will pop right out.
then loosen the bolt on the swaybar, and finally take out the bolt in the shock tower area and remove the uca.
you should have a good size prybar with you to assist aligning the swaybar into the new arm.
you did order new swaybar bushings right?

digieditny · #9 10-12-2010, 09:04 PM

I got 2 of these:

http://catalog.peachparts.com/ShopByVehicle.epc?q=&yearid=1984@@1984&makeid=63@@MERCEDES+BENZ@@X&modelid=6233%3AED|10000135%3AMBC|1518@@300TD&catid=241464@@Suspension&subcatid=241504@@Control+Arm+Bushing&applicationid=W0133-1642615@@Control%20Arm%20Bushing&mode=PA

Is that the swaybar bushings? See... Total newbie...

Well I would park the car on a one way street so I can park the driver's side towards the sidewalk.

After reading the issues, I'm SCARED! I'm screwed if the bolt that holds the upper control arm assembly to the frame doesn't come out. How likely is this? There probably isn't anything I can do before starting this to ensure the bolt will come out right?

If $220 sounds like too much, then maybe I can go find someone else. ARG!

digi

vstech · #10 10-12-2010, 09:07 PM

before worrying too much, open the hood, loosen the nut, and see if the bolt will turn.
odds are good you will have no issues, but NY is a rust belt state, and you could be looking at problems.

digieditny · #11 10-12-2010, 09:16 PM

The car doesn't have much rust. It was garaged for most if not all it's life. So hopefully it's not too bad in that area.

Ok, ok. I'll open the hood and turn the bolt tomorrow morning. If the bolt turns, then I might just go ahead and do it.

pictures I took the other day. Hmm looks rusted!

1 http://img840.imageshack.us/f/sdc11032c.jpg/
2 http://img830.imageshack.us/f/sdc11028.jpg/
3 http://img146.imageshack.us/f/sdc11027g.jpg/

digi

digi

Diesel911 · #12 10-12-2010, 09:29 PM

Often when people refer to the Sway Bar Busings they are speaking of the 2 round Rubber Donnuts that go on the Tip of the Sway Bar.

However, not related to the job you have in mind there is also a Sway Bar Busning where the Sway Bar Pivots on each side.

toomany MBZ · #13 10-12-2010, 09:36 PM

The part (see pic, nut end circled) you need to check for rust is under hood. Spray it with a penetrant before hand.

You do need two of those bushings you posted earlier, they go on either side of the UCA and the torsion bar.

Billybob · #14 10-12-2010, 09:41 PM

Quote:

Originally Posted by vstech

loosen the nut on the ball joint, and whack the side of the spindle it passes through. the joint will pop right out.
then loosen the bolt on the swaybar, and finally take out the bolt in the shock tower area and remove the uca.
you should have a good size prybar with you to assist aligning the swaybar into the new arm.
you did order new swaybar bushings right?

Just an "Old guy make it easy so you don't make it harder" variation on this method!

With the wheel off, loosen and take the nut completely off the upper ball joint stud. Spray a little PB Blaster, WD40, etc on the stud and the nut and then put the nut back onto the stud keep lubing it and working it back on and off so that it will easily turn.

Then you can reinstall the nut and use whatever method to separate the ball joint stud from the spindle. Then remove the pre-loosened nut.

This method will ensure that you can actually get things ultimately apart!

If you don't ensure that the stud nut will come completely off easily before you separate the spindle you can easily end up with the stud free from the spindle but be unable to remove the nut. If the nut has a hard time coming off the end of the stud's threaded section without the stud seized in the spindle it can be almost impossible to remove it as the stud turns with the nut. Sometimes you can use a giant pry bar to force the stud back into the spindle to create enough friction to counter hold the nut or you might have to break out the angle grinder and cut the nut/stud off to separate things. Either way a pain in the a$$!

Sometimes there is an Allen head counter hold but you have to often work the nut back and forth lubed up to prevent that from rounding out.

For someone who doesn't want complications this is a simple procedure to prevent a pain in the a$$, especially if you're out in the street and have to run an extension cord to power the grinder or wait for traffic to pass to use the 6' pry bar!!

digieditny · #15 10-12-2010, 10:10 PM

Great idea Billybob. Maybe I'll do that tomorrow morning. Do I still need to use a floor jack to support the lower control arm when I loosen, remove and tighten the bolt?

digi