What could be this knocking noise

[bowlofturtle]

I got this knocking noise in the front passenger side. I've given the car a good shake and looking for the obvious stuff like torn/bad boots or excessive play. NOTHING. Car doesn't pull or have anything weird issues. Held the wheel at 12 and 6, 3 and 9 wiggled everything and didn't see play.

Knocking noise happens at very low speeds over bumps and normally heading straight. Speeds of 7-10mph, no noise at all. Drives silent as can be. I can cruise on the highway with no noise at all but once I exit and roll into a residential street it happens.

This is on the infiniti, it has an upper and lower bolt joint setup, similar to most hondas. I've replaced upper ball joints a few years back. Lower arms about a year ago due to bad bushings. Had a shop look at it while doing an oil change and they suggested a bad strut mount. I replaced the strut mount and strut, no dice.

 

[Black Thunder]

possible sway bar link thats broken?

 

[Snagglefoot]

Possible play in the sway bar links.

 

[Propflux01]

Sway bars will clunk over bumps like you describe even if bushings 'look' good.

 

[mattd]

Check sway bar links and bar bushings

 

[RAR]

All of the above replies.. my Dodge Charger had new suspension put in the front (by me). The sway bar links were included in a kit I got so I ran them.

A month later, I got the knocking at low speeds on bumps. I thought maybe the kit parts were faulty, or the strut assembly I got had a cheap, failing strut mount. But then I got down under there and evaluated everything again. All was tight, except the links: they would move around easily and I could pull them up and down by hand.

Out they came and I put a set of Delphi links from RockAuto in (all of $30 shipped), and the Charger rides great, even over the washboard gravel road I take once in a while. No clunks, thumps or rattles. For these cars, that is an accomplishment.

 

[bowlofturtle]

Thanks guys.... I'll definitely look at the end links over the weekend.

One part that bugs me is why only at low speeds. You would think at high speeds more flex would happen. It bugs me that on the highway the car is dead silent.

 

[spasm3]

Make sure your lugnuts are tight.

 

[Danno]

Thanks guys.... I'll definitely look at the end links over the weekend.

One part that bugs me is why only at low speeds. You would think at high speeds more flex would happen. It bugs me that on the highway the car is dead silent.

It's the slower, speed sharp bumps where the noise would be loudest, highway bumps don't have the same effect on the end links.

 

[bowlofturtle]

Well it’s definitely not the sway bar. I bought new links as they were only $20 each.

when I went to install it seemed easier to pull the whole bar off and do the end links off the car.

I drove around the block without the front bar and the noise was still there. So 100% not sway bar related.

I had the pass sided up and had my brother put a pry bar under and moved it up and down while I was under the car. To look for any. Nothing, I even held on to tie rod/ lower ball joint / upper ball joint rear control arm to see if I can feel it. Nada. So lost.

 

[bowlofturtle]

Make sure your lugnuts are tight.

That was my first instinct. Since then I've checked them like 4 other times.

 

[ollie]

Your symptoms describe a bad motor mount.

 

[oggb]

So did you replace both the front lower control arms AND the compression rods, or just the control arms?

 

[bowlofturtle]

So did you replace both the front lower control arms AND the compression rods, or just the control arms?

Just lower control arm. The common issue with this chassis is the lower control arm bushing tearing. One was torn, I replaced both arms.

compression rods bushings looked good.

 

[The Critic]

Probably the compression rod bushings or the joint itself.

 

[bowlofturtle]

Probably the compression rod bushings or the joint itself.

It's on my list of likely suspects (since its very common on these cars) but I can't make the noise the happen on jack stands to confirm nor is the bushing torn.

 

[carviewsonic]

How about the struts themselves? My '05 Park Avenue had the same knocking sound you described, but from the back. I just replaced the rear shocks, and problem solved! I didn't suspect them from the start, because the car has low mileage (24k miles). The knocking sound was really annoying to me, so I went through everything I could think of, except for the shocks. Wish I had tried the shocks earlier, it would have saved some frustration.

 

[bowlofturtle]

How about the struts themselves? My '05 Park Avenue had the same knocking sound you described, but from the back. I just replaced the rear shocks, and problem solved! I didn't suspect them from the start, because the car has low mileage (24k miles). The knocking sound was really annoying to me, so I went through everything I could think of, except for the shocks. Wish I had tried the shocks earlier, it would have saved some frustration.

The side strut and everything associated was swapped out, the only thing kept was spring.


Moved around wheels today. Noise still there Still just find it odd that on the highway its dead silent.

 

[HoosierJeeper]

I've had that happen on my Liberty and my 15 Cherokee. It was like a loud knock/pop that you could feel in the floor over bumps. Never noticed anything when going faster. For the Liberty, I even asked on here and quite a few people said motor mount.... turned out to be a bad ball joint or tie rod end. Took it in for an alignment after not being able to find anything wrong myself. Replaced the UBJ, LBJ and tie rod end on the passenger side.

Clunk from driver's front - only going over driveway curb

Update: took it in for an alignment, on the passenger side it needed: an UBJ, an LBJ and a outer tie rod end. I replaced all that stuff and it's gone. So this one was suspension related.

bobistheoilguy.com

On my Cherokee....same noise, I checked everything for play, nothing at all. Took it to one of my friends that used to own one of the larger shops in town that's a local legend in automotive circles (he's retired now and just plays in the garage all day), he put it up on the rack and was able to find one angle and with a 3' pry bar where there was some play in the passenger side lower ball joint. Replaced it and was good to go. Moral of the story, really double check ball joints and tie rod ends. I've had so many suspension noises over the years that drove me nuts and were hard to diagnose and they turned out to be ball joints. The shock mounts I've had go bad didn't clunk at all, they just chirped.