Can you eliminate a noise by just putting the car up on a lift?

Huskymaniac · #1 06-15-2011, 09:21 PM

I had this moderate knocking/rattling noise in my front end. It seemed to be worse at low speed over uneven bumps. It didn't go away when braking. My mechanic and his co-worker looked at the suspension components three times and couldn't find any issues with the usual suspects. When I had my tires changed over from snows to all-seasons and an oil change, I had him look again. He said he didn't see anything. When I drove the car home, I noticed the noise was gone! I asked him if he tightened anything or lubed anything and he didn't recall doing either. He suggested something may have shifted when the car was unloaded on the lift.

Well, over the past month or so, the noise has slowly returned. At first it was very faint but it is getting back to almost where it was before it disappeared. Does this point to any component specifically? What could shift when the car is on a lift and shift back slowly over time?

Hocrest · #2 06-15-2011, 09:28 PM

Strut top?

XT6Wagon · #3 06-15-2011, 11:46 PM

maybe the swaybar got moved a little to one side or the other?

Dunno. Don't forget to check the back suspension if it goes back up on a lift as sometimes sound wanders to strange places.

Huskymaniac · #4 06-16-2011, 05:22 AM

Quote:

Originally Posted by XT6Wagon

maybe the swaybar got moved a little to one side or the other?

Dunno. Don't forget to check the back suspension if it goes back up on a lift as sometimes sound wanders to strange places.

I wondered about that. Maybe I should grease or replace and grease the bushings.

Huskymaniac · #5 06-16-2011, 05:25 AM

Quote:

Originally Posted by Hocrest

Strut top?

I looked at the parts diagram for the front struts and I can't visualize what would have moved. The one thing that stood out were the upper and lower spring seats.

Hocrest · #6 06-16-2011, 05:50 PM

Pull the large "D" shaped plastic cap in the rear corners of the engine bay and you will see the top mounts. There is a metal ring that fits into the hole on the frame and then a rubber bushing between the ring and the bearing.
If that rubber is dried and cracked, jack up that corner and reach under the fender to shake the strut. You really shouldn't have any movement. I've had movement in there make occasional noises over bumps. It would vary with how things lined up as the strut loaded/unloaded over bumps and around sharp turns.

Be careful, if that is your problem you can pull the strut out of the top. Especially if you push down on a torque wrench trying to get 150lbs on the axle nut

alia176 · #7 06-21-2011, 09:41 AM

I have some inputs that may help the OP (original poster). Check the easy items first:

- remove both tires and disconnect the driver side sway bar end link from the driver front strut housing. Leave the other end link connected on the pass side.

- now, move the driver side end link up down, side to side and look for play.

In my case, I had play in the following two areas:

- the rubber boots on the end links were shot and this introduced play.
- the driver side end link is connected to the sway bar using splines. This connection came lose on my car and simply tightening the nut took care of it.

Even after replacing ALL front strut items (upper/lower rubber seats, upper strut mount, new strut cartridge), I STILL had a crazy clunking. This was due to the two items I mentioned above.

So, check the easy stuff first. Maybe remove the sway bar end links from the struts and move the sway bar out of the way and then go for a careful drive to see if the noises go away? Just a suggestion.

Good luck.

Huskymaniac · #8 10-14-2011, 05:55 AM

Update on this.

The knocking noise has slowly come back over a four month period. I was just starting to hear it again when Nate came through our area and now it is almost back to where it was before the car was put up on a lift.

One new observation is that I can actually feel the knock with my left foot. I noticed that yesterday when I was pushing down on the floor (just behind the wheel well area) to scoot myself up in the seat while driving. When I heard the noise I could feel it under my foot like something was knocking the other side. I haven't noticed it with my right foot but, then again, that foot is usually on the gas.

Would that point to something specific? I was thinking the sway bar bushings were sticky and the bar was shifting over too far over time, as one person had suggested. It doesn't look like it has but it is hard for me to judge how close is too close between the bar and the mounting hardware. I don't know how much it moves while driving.