Over this past Summer, I've been slowly rebuilding the front end of my 300SD. Last year I would occasionally get a popping sound when turning the wheel while stopped, and had a rattle while slowly going over bumps. The rattle went away when I replaced the guide rod mounts. But after replacing the passenger side tie rod, upper control arm and center link I'm getting a low pitched popping sound when I turn the wheel while stopped or moving slowly. One thing to note is that the Uro idler arm bushing a installed has already crapped out which is giving me some play in the steering linkage. The popping became much worse today after installing the center link. The driver's side tie rod and upper control arm are still old, so is it possible that the new center link is putting more force on that tie rod and giving me the noise? Also, how do I check for a worn steering coupling? thanks

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'81 300SD

Difficult to say - loads of possibilities there.

Do you realise that by turning the steering at a stand still you are not only damaging your tyres but adding unnecessary forces to the steering components? Can I encourage you to get the wheels rolling before turning the steering wheel?

To find worn steering or suspension components I've found that putting the front wheels on slip plates helps a lot. You can then turn the steering wheel or even the wheels easily without damaging stuff. Be careful though - cars can slide off slip plates.

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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

It's only when I begin to parallel park that the car is almost at a stand still and I hear the popping. I'll also hear it when slowly turning in and out of the driveway.

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'81 300SD

It does sound like the end of the brake stay popping in the LCA...

...but don't put yourself through a wild goose chase - check everything methodically.

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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

I had an alignment done perhaps 18 months ago and they forgot to tighten several things on the drivers side. When I braked the car pulled to the left, and I was stumped. I bought new caliper at the yards and then found some loose nuts in the suspension. Then I found the thrust bearing was loose and had to buy a new one. Since then I've had a sometimes soft and other times very loud "click" (or popping) from the drivers wheel area, as if something is jumping threads. I've replaced many items and my indie finds nothing out of whack. I replaced the sway bar bushings and the click was reduced, but now it's coming back. When I accelerate and then slow down and turn left the click is loudest, but it does sometime happen when I slow down and turn right. I'm at a loss because on a lift everything appears fine.

If you find the source of your "click" let us know, and I'll do the same.

Linoleum tiles make good slip plates.

See if you can isolate the popping by turning the steering wheel with one wheel off the ground.

Sixto
87 300D

the popping sound is probably lower ball joints and or worn LCA bushings.

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1985 300TD Turbo Euro-wagon
1979 280CE 225,200 miles
1985 300D Turbo 264,000 miles
1976 240D 190,000 miles
1979 300TD 220,000

GONE but not forgotten
1976 300D 195,300 miles
1983 300D Turbo 175,000 miles

http://i42.photobucket.com/albums/e3...e485-1-2-1.jpg

I tried a couple of different methods to find the noise. First, with both tires on a slab of cardboard my girlfriend turned the steering wheel back and forth while I inspected the drivers side wheel. I wasn't able to find the noise with that method. Second, with the front end on jack stands, I moved the drivers side wheel back and forth and found a lot of play in the pitman arm. I'm hoping that some of that play will subside when I replace the piece of junk URO idler arm bushing with a Lemfoerder later this week. I also read on an old thread here that someone eliminated a popping sound by adjusting his steering box. I'll try that too since sometimes the pop sounds like it is coming from underneath the dash right on the firewall.

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'81 300SD

I just had a similar noise which was freaking me out. I think I have a bad shock because loosening the top shock nut made it stop. Replaced the nut and the noise was back

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My occupational hazard bein'
my occupation's just not around...
1980 300SD
1980 300SD

From your latest description, and referring to the things changed already, it sounds like the Driver's upper control arm bushings are worn out.

When you have that area apart, you might as well change out the torsion bar bushings. Fortunately, most of the suspension parts are reasonable in price but will give you a work out while changing them.

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Sam

84 300SD 350K+ miles ( Blue Belle )

I'd be cautious when playing about with the steering box. Please have a look here =>

http://www.peachparts.com/shopforum/diesel-discussion/303379-what-feeling-will-properly-adjusted-w123-w116-w126-power-steering-box.html

__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

Since my last post I've replaced the idler arm bushing, driver's side tie rod and driver's side upper control arm. The exact same popping noise still exists. I'm tempted to put the old center link back on since this wasn't a problem until I replaced it. I tightened the steering box 1/4 turn with no luck(I turned the allen nut counter clockwise). When I move the wheels from side to side while the car is jacked up, I can hear a click in the steering box when the wheels are in the same position as when I hear the pop when parallel parking. I heard this noise before the adjustment.

One thing to note is that when I replaced the driver's side tie rod, the popping went away but the alignment was way off. When I lengthened the tie rod to center the steering wheel the popping was at it's worst. Also, I checked the lower ball joint and there is no play. There is a little bit of play in the hub, possibly wheel bearings, but nothing worse than the passenger's side. Hopefully an alignment will finally give me some answers.

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'81 300SD

If there is enough play in the hub that it is visible, then you have bearings that are either way too loose or completely gone. In fact, if the play is visible, you are on the edge of a dangerous situation. (The spec. is .0005" with a dial indicator.)

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Sam

84 300SD 350K+ miles ( Blue Belle )

Wow, I'll get it into the shop Monday. Since there isn't any squealing noise, vibration or heat from the wheel, it never occurred to me that it might be dangerous. In fact, I'm pretty sure that the 240D I drove for 70K miles had a tiny bit of play in the front left wheel. Thanks

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'81 300SD

Sometimes when the control arm mounting bolts arn't quite tight enough the will move slightly when stressed (driveway entrance or turning the wheel while stationary) resulting in a snap or pop sound. Don't over look the basics.