Got the wheel off and took and isolated the issue to the lower control arm. Here's what I am dealing with in video below:

https://youtu.be/jP-bubjT5rU

s you can hear, there's creaking coming from the back part of the control arm when it's pried. There are no cracks in the springs. I loosened the bolts one by one for the lower control arm bushing and applied fluid film. I also sprayed fluid film on both the inside and outside of the lower control arm bushings. Everything is secure. I applied the spray to the chassis where the tabs and square bolts are located. I didn't open the guide rod housing. Despite these efforts, the loud creaking continues.

Before I dive further, do you have any suggestions based on what you can see? Thank you.

__________________
Theseus

Instragram: doss_project
1984 300SD - 930 Blue, OM 617
Murfreesboro, TN

Theseus owned a ship in Greek mythology, and when a part of the ship needed replacing, it was replaced. Eventually, everything was replaced. Is it the same ship? (I own the car of Theseus. )

mine would creak intermittently during turns or over speed bumps. I drove it on a trip 500 miles and it was totally quiet until I reached my destination. It then proceeded to creak at every turn for the next 7 days. It was a great vacation. Nice car, loud racket. It was the hood pins. I cleaned all the old grease out and lubricated the hinges, latch and pins with heavy grease. Problem solved. If I had not parked my butt where it should not have been, I would probably have spent a small fortune on suspension parts by now. That was 15 years and 100,000 miles ago. Still driving the same quiet Mercedes with no creaks and no rattles. Good luck.

You look like you’re really close.

I don’t think that is called the lower control arm.

It’s called something like the guide rod mount. Anyhow it has a big rubber bushing and some captive nuts that can get really corroded up in there. You should disassemble it and see what is going on.

PeachPartsWiki: Suspension Bearing Bracket guide rod mount replacement

__________________
79 300TD “Old Smokey” AKA “The Mistake” (SOLD)
82 240D stick shift 335k miles (SOLD)
82 300SD 300k miles
85 300D Turbodiesel 170k miles
97 C280 147k miles

Cool, glad my situation is able to help yours too. The one thing I did with that pushing on the lower arm control support was unscrew the bolt and inspect it and look at the square bolt and I didn’t see anything on. Maybe there was something going on inside that bushing.

I ended up spraying fluid film on that whole area in the creek source first. It didn’t seem to do anything unfortunately. And then sprayed other various areas, even in the chassis and those bolts, that may be the cause but I also didn’t get anything to cause a squeak to go down. I even got out my camera endoscope and put it through the chassis, but didn’t see anything unusual.

Anyway, I take my car over to the airport for a business trip. Couple days later I return and lo and behold this noise is gone! It’s been dry, and I haven’t had any creaking noises since. So something wasn’t lubricated deep inside somewhere and eventually that fluid film snuck into it with lubricated it.

Without a doubt, I’d say it’s lower arm control support. Somethings going on in the bushings. Oh noted and inspect it next time I have to get to that point.

Replaced the Suspenion Bearing Bracket guide rod mounts back when I had my W126 300SD.

If I had to do it over again, I would simply replace the whole Unit (Item 110 in the Thumbnail drawing of Post #9 in the Thread below),
with the pre-assembled MB replacement.


About to tackle guide rod bushings on '81 300SD

Left side: MB Part Number 1263301243
Right side: MB Part Number 1263301343

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78 W116 300SD 'Desert Rose' new as of 01/26/2014
79 W116 300SD 'Stormcloud' RIP 04/11/2022

I just wanted to mention this. After watching the video of the guide rod support mounts squeaking when you pried on the slot I sprayed some silicone oil right there on my car.

It really quieted down. I am now rethinking all my conclusions about the swaybar mounts making noise. I think I need new guide rod mounts.

I replaced the guide rod joints (ball joints?) a few years ago…wow, it has been 13 years now. But I never changed the mount with the big rubber doughnuts inside. That was likely a dumb move. They looked okay but I think I’ve had a squeak in there for ten years and I’ve just put up with it.

Thanks for the post Theseus.

Now I’m wondering if I should find a set or perhaps just keep spraying silicone oil in there.

ETA- These look like the bushing pn

1263333314

1263335414

Ouch they’re expensive. Given all the work to press them in I don’t think it’ll be wise to try to save a few bucks and buy Meyle or Febi.

__________________
79 300TD “Old Smokey” AKA “The Mistake” (SOLD)
82 240D stick shift 335k miles (SOLD)
82 300SD 300k miles
85 300D Turbodiesel 170k miles
97 C280 147k miles