Knocking in driver side wheel area


#1

I have a 2000 Monte Carlo. I recently noticed a knocking sound in the driver side wheel area whenever I pull off or make turns. My mechanic said it was my rack & pinion bushing & that the whole rack had to be replaced, I just had it replaced last yr. So I get it replaced & it’s still making the noise. Brakes & rotors were replaced in March as well the struts. The tie rods were replaced last in 2014. I don’t know what to do now. Does anyone have an idea of what I can do?


#2

Since none of us can do anything more than speculate about the cause of the problem, you really need to get a new mechanic, as your current mechanic just appears to be throwing expensive parts at the problem. Have the new mechanic check the ball joints, and everything else in the front end, + the CV joints. Bad motor mounts and/or transmission mounts are also a possibility.

If you don’t know which new mechanic to go to, you might want to use the Mechanics Files link at the top of this page. This will bring you to a database that you can search by zip code.

With any luck, this may just turn out to be a loose exhaust pipe that is hitting the underside of the chassis.


#3

Does this knock sound only occur once per episode or is it a repeated series of knocks; say 4 or 5 in a rapid manner?

The possible causes could be narrowed down a bit based on knowing that bit of information.


#4

A-arm bushings. Anti-sway bar end links. Sway bar bushings. Broken end of sway bar. Happens often on GM cars that use pressed end tube sway bar design.


#5

If this happens while you are turning the steering wheel left or right but not while you are holding the steering wheel stationary it is probably a binding steering intermediate shaft. A really simple fix is to inject some really thick oil (not grease) into the hollow shaft. To get at it pull back the bellows at the base of the steering column and you will see a small universal joint. Inject the oil into the inside of the hollow shaft that is just below the u-joint. This really works great.

This is if you are hearing a series of several knocks as @ok4450 alluded to.


#6

The description sounds more like an inner CV joint to me.
Inner CV joints are made with a trifurcated (three-pronged) assemblage with a bearing on each prong that rides in a grooved housing. One of their two primary functions is to freely allow the axle to get longer & shorter as the steering knuckle goes through it’s movements. It does this by the prongs with the bearings sliding back & forth in the housing grooves. Sometimes the pronged assembly wears its own grooves in the housing, and when the axle tries to change length when turning the assembly fights the movement, trying to stay in its grooves. That makes knocking noises.


#7

I’ve always found when a knocking noise occurs while turning it’s a worn outer CV-joint as it’s the articulating CV-joint.

The inner CV-joint is the plunging CV-joint which allows the axle shaft to get longer and shorter as the tire goes over bumps. A worn inner CV-joint will have the same symptoms as a worn U-joint. A single clunking noise when stopping and starting.

Tester


#8

I really hope the Op gets back to us to answer @ok4450 s question.

If the knock continues when he is not moving the steering wheel then I’ll agree with @“the same mountainbike” and @Tester .

If the knock occurs only when moving the steering wheel, even if the car is not moving then I can almost guarantee it’s the steering intermediate shaft binding. This was a common problem on early 2000’s GM cars. The problem was that GM decided to use a slippery coating (probably teflon?) instead of a real lubricant. Once the coating wears off it starts to bind. Don’t forget, the shaft is connected to a little universal joint which causes it to pulsate back and forth just like any u-joint would. I’ll bet many racks have been unnecessarily replaced on these cars due to this. Note that the OPs mechanic said it was the rack & pinion bushing. Well, he was only a couple of inches away.

I had this problem on my '01 cavalier. I sprayed some white lithium grease into the shaft and it fixed it instantly but it lasted only a few months. Then I injected some very thick oil into the shaft four years ago and it’s still good.


#9

I presume you mean the front driver’s side wheel well. Besides what’s mentioned above, all good ideas, take a close look at where the upper strut attaches to the body of the car, right at the top of the wheel well usually. Notice anything loose, bent, or otherwise unusual? Compare it to the other side if need be.

One other idea, especially If this is a transverse configured engine, take a look at the engine or transmission mount in that same area. It could be worn and getting loose. It’s usually easier to check by goosing the rpm a little and checking for an unusual amount of movement at the mount. That’s unlikely given the symptoms occur when turning, but it’s a possibility and is easy enough to do.


#10

The inner joint also articulates some, but the noise comes from the bearings on the tripod being pulled out of the grooves they’ve worn in their casing as the axle changes length. Outer joints will usually make a clicking noise as the little steel balls go back and forth in their grooves.

There’s no way of knowing what the OP’s problem actually is. All we can all do is offer possibilities and hope he takes it to a shop that can diagnose it properly. It doesn’t sound like the one he’s currently using is doing so. It sounds like they’re guessing and changing parts… starting with the most expensive one, the rack.

To help the OP understand my suggestion, I’ve taken the liberty of attaching a link to diagrams of the CV joints. Hopefully he can envision the inner joint’s innards sliding in and out as the steering knuckle moves around and changes the length of the axle.
http://www.bing.com/images/search?q=inner+cv+joint+diagram&qpvt=inner+cv+joint+diagram&qpvt=inner+cv+joint+diagram&FORM=IGRE