85 SD Suspension ID Help, Creaking Sound (Pictures)

[1985 300SD Sady]

1985 300sd 205k miles. New lower ball joints, tie rods, and new Michelin tires at 197k miles followed by an alignment at the dealer.

I have been getting a creaking sound from the drivers front corner of my car. It is coming from the suspension. I used some silicone lube to try to isolate where the problem is located (as per the instructions from the results of my searching this forum) and have not been able to stop the noise.

My rubber bushings dont look too hot, also there is a rust hole in the body of the car Pictures follow. (Questions are below pictures.)

Let me know if I am calling everything by the correct name.

I am planning on fixing up my suspension... I am just trying to figure out what needs done.

I would like to get all new shocks while Im replacing bushings etc. I think the shocks on there are stock (Sachs with one blue stripe? was that stock?) I want to replace everything with bilstein from what I have read.



1. What is the name of the bushing that looks torn/ripped? Upper Ball Joint? This is the upper control arm correct? and then the sway bar on the right? or the torsion bar? Then I know the shock and spring locations. Do these look bad?



2. Is this the sub-frame mount? Is the guide rod to the left? Is that rust horrible? What can I do? Would any of these create my sound? (it was raining which is why it looks wet.)



3. Is this the lower control arm/bushing? Do these go bad?



4. Another view of the first picture... Upper control arm? Upper Ball Joint? Does it look bad?



5. Is this the sway bar or torsion bar? Do those bushings go bad and make noises?

All help is welcome! Thanks in advance

[sixto]

1) That upper balljoint looks worn. The upper balljoint is part of the upper control arm. I haven't seen it offered for sale separately. You might as well replace the swaybar (technically not a torsion bar since there are coil springs) bushings into the control arm. Douse the bolt that goes into the swaybar with lots of penetrant.

2) Terminology is hazy here. The aluminum piece with two hefty bushings that go into the frame I call a guide rod mount. The bushing at the center of the picture looks okay but I can't really see the condition of the rubber. The guide rod terminates in rubber bushings at the lower control arm (spring and perch must come off to replace these bushings, I don't know why), and something of a ball joint at the guide rod mount. When the guide rod attachments are worn you'll get a clunk as you slow down the car or hit a road surface elevation change.

3) Those are lower control arm bushings and they can go bad.

4) Yes, yes, yes.

5) That's the swaybar. I suppose those bushings can go bad. A spritz of SilGlyd should tell you if that's the source of the noise.

Good luck.

Sixto
93 300SD

[1985 300SD Sady]

Thanks Sixto. That explanation was exactly what I needed.

I think Im going to go ahead and get all new shocks, a new steering damper (old is original) and new front upper control arms. Also, I am going to replace the rear sway arm links because Im getting the rattle that is talked about in the archives. Im going to debate it for a while longer, and talk to some local people about it.

I am getting a sort of clunk or a thunk noise, but only as I am slowing down to a stop and going about 10ish MPH. I figured it was from the transmission since it started happening after I disconnected the vacuum line going to the tranny. Any way to test this?

Thanks again.

[MattBelliveau]

I am getting a sort of clunk or a thunk noise, but only as I am slowing down to a stop and going about 10ish MPH. I figured it was from the transmission since it started happening after I disconnected the vacuum line going to the tranny. Any way to test this?

...yeah, try hooking the vac line back up If it goes away, that's your problem.

[barry123400]

Any suspension component with a bad boot I would check for play. If none is evident then remove the bad boot, liubricate and install a new boot. The boots can just rot with age. You have tried pushing the fenders down and listening for the source of your noise? Or having a friend push while you listen. That proceedure might locate it. Worth the effort though even if it does not localise the noise. Too easy and cheap a test to bypass.

[1985 300SD Sady]

Originally Posted by MattBelliveau

...yeah, try hooking the vac line back up If it goes away, that's your problem.

When I did hook it back up, I didnt notice anything, but I wasnt listening specifically for it...

So Ill hook it back up and take a spin.

Thanks for that thought.

[MattBelliveau]

I would hook it up, and leave it for a few days while you drive it. Tehn you will know. If it does it less, but still does it, your modulator may be about to take a poop. Curious, what prompted you to unhook it?

[1985 300SD Sady]

Originally Posted by barry123400

You have tried pushing the fenders down and listening for the source of your noise? Or having a friend push while you listen. That proceedure might locate it. Worth the effort though even if it does not localise the noise. Too easy and cheap a test to bypass.

Yes, I had my uncle push on the car while I was under it listening and feeling.

I could not pinpoint where the sound was coming from.

I Can feel the vibration in the guide rod and the uppercontrol arm and sway bar... so that doesnt really help either.

I am going to go and try to isolate the sound using silicone lube again when the rain stops.

Ill let you know.

[1985 300SD Sady]

Originally Posted by MattBelliveau

I would hook it up, and leave it for a few days while you drive it. Tehn you will know. If it does it less, but still does it, your modulator may be about to take a poop. Curious, what prompted you to unhook it?

Well, the vac. valve atop the IP is not changing the amount of vacuum going to the transmission.

This made the transmission shift really really really badly... way late and sometimes double shifting.

Unhooking the vac. line made this go away.

The modulator holds vacuum for over 10 minutes... (it would hold longer, I just stopped the test there.) Doesnt that mean that it is good? Could it still be out of adjustment?

The car is not fun to drive in any way with the vac. system hooked up like it was.

[SD Blue]

From your photos, you are definitely in need of upper control arms. With the condition they are currently in, you probably are hearing several popping noises, especially when braking. Not to mention the possibility of severe tire wear. Pretty easy repair.

The sway bar bushings are a little unclear in the photos but the tend to either give you a harsh ride or a lot of wallowing when they wear. Very inexpensive and straight forward repair.

Yes, the lower control arm bushings can go bad. They usually give a slight shifting feeling in turns and cause a lot of tracking on uneven pavement. They are a little more involved and you will need an MB spring compressor which is available to rent here on this forum.

The main thing that concerns me is that subframe mount. That is some pretty severe rust in a very critical area. I would get that looked at by someone very familiar with MB's and rust repair as soon as possible. The "clip", bushings and hardware are all replaceable in that area.

[1985 300SD Sady]

Originally Posted by SD Blue

From your photos, you are definitely in need of upper control arms. With the condition they are currently in, you probably are hearing several popping noises, especially when braking. Not to mention the possibility of severe tire wear. Pretty easy repair.

The sway bar bushings are a little unclear in the photos but the tend to either give you a harsh ride or a lot of wallowing when they wear. Very inexpensive and straight forward repair.

Yes, the lower control arm bushings can go bad. They usually give a slight shifting feeling in turns and cause a lot of tracking on uneven pavement. They are a little more involved and you will need an MB spring compressor which is available to rent here on this forum.

The main thing that concerns me is that subframe mount. That is some pretty severe rust in a very critical area. I would get that looked at by someone very familiar with MB's and rust repair as soon as possible. The "clip", bushings and hardware are all replaceable in that area.

Alright, well Im going to buy new shocks, new upper control arms, new sway bar bushings and go to town.

I will get that subframe mount looked into... but wouldnt the spring need to be removed to get them done? Should I just completely rebuilt the whole front end and be done with it?

Would replacing the shocks, upper control arms, and sway bar bushings do anything to my alignment?

I forgot to mention, when I did the tie rod ends etc. I got new michelins before the alignment.

[1985 300SD Sady]

I hooked up the vacuum to the transmission and the clunk/thunk sound went away... so I guess that means my guide rod bushings are not causing that.

Do you think I should just do what I can get out without taking the springs out, or just rent the compressor, take the springs out and completely renew all the rubber etc?

[SD Blue]

It depends on a couple of factors, namely $$'s and time. Is this a daily driver?
If not, then it might be just as "easy" to get all of your parts together first then rent the spring compressor.

(Not to mention, pumping a little iron and getting in shape! Because rebuilding the suspension will be a work out and make you feel every bit of your age. )

I would resolve the rust issue on that subframe mount before tackling the rest.

[1985 300SD Sady]

Originally Posted by SD Blue

It depends on a couple of factors, namely $$'s and time. Is this a daily driver?
If not, then it might be just as "easy" to get all of your parts together first then rent the spring compressor.

(Not to mention, pumping a little iron and getting in shape! Because rebuilding the suspension will be a work out and make you feel every bit of your age. )

I would resolve the rust issue on that subframe mount before tackling the
rest.

I got money, I have enough time to get it done.

It is a daily driver for the most part, but I dont have to have it... I walk the 20 feet to high school and do not work during the school year (yet)

When I want to go out with friends I can bum a ride or use one of the parents cars.

What would all the parts include?

Front - Upper Control Arms, Sway Bar bushings, Shocks, Lower Control Arm bushings, Sub frame rubber, Guide rod bushings?

Rear - Shocks, Sway bar bushings and links, should I take the springs out while renting the compressor and do the subframe bushing back there also?

Did I miss anything?

I think I should be able to handle the work... Im 17, and I can get a hand from someone if I need it.

Should I even attempt to correct the rust issue myself? where do I go for that kind of damage?

Thank you for your replies.

[whunter]

Rust needs to be stopped, cut away, and repaired.

The three bolts you are asking about are part of this.
http://www.peachparts.com/Wikka/W126GuideRod

I need to see a better picture of the light green circle area.