Clack on Slow Turns

[Skippy]

I thought I posted this on Sunday, but I guess I forgot to hit submit. On my '83 300D, I sometimes get an audible clack on slow turns, more often left turns, but on the way to work today it did it on a right turn. I had the front wheels off the ground and couldn't find any looseness in the suspension or steering, except for the 380,000 mile slop in the steering box. However, the top mounting rubber for the right side engine shock seems iffy. Could this be my clack?

[merc lover]

Check out your CV axles/joints. Check the boots for tears, etc. Also, per Alec's suggestion, turn the car to the right and left while driving slow. Have a partner/friend stand outside the circle turning radius and listen carefully. sometimes they can hear if it is from the front of the car or the back.

I took my car to a local school parking lot which was nice and quiet so we could listen carefully......

[Usaguy]

Originally Posted by merc lover

Check out your CV axles/joints. Check the boots for tears, etc. Also, per Alec's suggestion, turn the car to the right and left while driving slow. Have a partner/friend stand outside the circle turning radius and listen carefully. sometimes they can hear if it is from the front of the car or the back.

I took my car to a local school parking lot which was nice and quiet so we could listen carefully......

This is true for front wheel drive but not for rear wheel drive axles.

When turning at low speeds the rear wheel drive axles are at the same angle as when driving straight

[bsmuwk]

Does this noise occur only on acceleration in that turn? Is it a single clack, or is this noise speed related? My vote is with the axles as well, they ARE a wear item... especially considering how many miles you may have on them!

Originally Posted by christuna

This is true for front wheel drive but not for rear wheel drive axles.

When turning at low speeds the rear wheel drive axles are at the same angle as when driving straight

CV's will make noise whether they're used in driveshafts, FWD axles, or RWD axles. They're just more readily audible and more frequent failures on fwd vehicles because of the various angles and torque applications they see. The noise in any application is the same.

[merc lover]

Years back, one of my CV axles failed while I was approximately 600 miles out of town on business. I took the car to the local MB dealer who wanted a lot of $$$$$ to repair the problem. I took a chance and drove the car 600 miles home, clacking all the way. I was nervous the car would drop me on the side of the highway but luck was with me and I arrived home safe and sound.

I then scheduled a repair with the local indy who replaced the offending CV axles for around $500. Now, this was around 25 years ago but still saved a lot of money over dealership pricing.

[Skippy]

The noise is coming from the front, so it isn't axles. Single clack per event.

[Alec300SD]

Ball joint in item # 26 is my guess.

[Graham]

I had clacking on slow sharp turns on my 107. I changed just about everything before I found the problem was the subframe. I removed the reinstalled and torqued the bolts not sure how 123 compares.

[Skippy]

Originally Posted by Alec300SD

Ball joint in item # 26 is my guess.

I just had the front suspension rebuilt. Okay, by "just" I mean 85,000 miles ago in 2006. I'm afraid you may be right.

Originally Posted by Graham

I had clacking on slow sharp turns on my 107. I changed just about everything before I found the problem was the subframe. I removed the reinstalled and torqued the bolts not sure how 123 compares.

I think W123 and R107 front suspensions are very similar.

[Graham]

Originally Posted by Skippy

I just had the front suspension rebuilt. Okay, by "just" I mean 85,000 miles ago in 2006. I'm afraid you may be right.

I think W123 and R107 front suspensions are very similar.

Yes, I think they are similar. The noise on the 107 was very repeatable. Only occurred when making tight slow turns. Might be worth at least inspecting the subframe bushings & bolts.

On my 300D, I had noise from front suspension, but it was more on bumpy roads, not when making slow turns. We replaced the guide rod mounts as well as the guide rod to lower control arm bushings. Had to remove springs This did eliminate the noise.

[carock]

If this was an older 300 D with steel wheels the problem could have been a lug nut that came off and was clacking inside the hub cap. I was surprised how often I saw that happen in the old days when the cars were new.

[Skippy]

Okay, I might finally get to do something with it this weekend. How do I check the guide rod mounts? Also, it's starting to clack on both left and right turns. And it needs a steering box.

[Skippy]

I'm in the middle of replacing the steering box. I broke a tie rod end in the process of doing that, so I ordered one. I also pushed and pulled on everything I could in the front end and decided that the drag link and idler arm are knackered, so I ordered a new drag link and an idler arm rebuild kit. I couldn't get the guide rod mounts to make any noises, but I looked under the rubber boots and the material underneath seems to have deteriorated, so I ordered new guide rod mounts. Since the springs need to be compressed to change the guide rod mounts, I ordered lower control arm bushings to install at the same time. Parts should be here around 10 December. Does it sound like I'm on the right track?

[engatwork]

You do not have to remove spring to replace item 26 IIRC.

[Graham]

Originally Posted by engatwork

You do not have to remove spring to replace item 26 IIRC.

True, but you do to get at the bushings at the other end of the guide rod in item 5 under item 20. Actually you don't have to. Method is posted here somewhere that uses a come-along. We took the springs out.