Hi all, last night I replaced the front sway bar bushing and end links on my 2012 G37x sedan (58k miles) because of some front end looseness noise over road imperfections. The bushings were okay but I swapped them anyway, and the links were sloppy although little to no detectable play. Anyways, the looseness noise remains however more noticeable at higher speeds. I got back under tonight to confirm everything is tight, and everything is. If I bang up and down on the sway bar with my fist, there is no noise, but if I bang laterally on the bar with my fist (towards the back of the car), I can hear a faint rattle looseness, even though everything is tight.

So I start to think back about something I did and wasn't 100% sure was right, and if it would even matter... the upper portion of the original links had a washer sandwich between it and the front side of the lower control arm (as can be seen in the factory service manual), and weird only up top and not at the bottom also. The new Moog's (K750209 and K750210) didn't come with that washer, so I installed the new Moog's using the original washers. Is it possible this is the source of the noise and I shouldn't have installed the washer. I wouldn't think, but curious what you think.

Thanks,
Mike

 

Pretty unlikely. Sounds like you had noise prior to the install and the noise still exists after the install. I would imagine its just something else loose on the car. What type of noise is it? Do you only hear it at higher speeds?

 

Everything else I bang and pull on is tight.
I only hear it when I bang on the sway bar from front to back. And its not like I'm hammering on it hard enough to transmit the force further into the suspension, and I can feel it there.
Sound... that's a tough one... a subtle single rattle like you'd normally hear in a worn link. Sorry, not trying to sound like a smart a$$.
Initially after install there didn't seem to be much noise evident at speeds under 45mph, but tonight it seems to be evident above 20mph, which led me to double check the tightness and all hardware was tight.

 

Oh ok, so you have confirmed the noise is from the front sway. Got it. Sounded like you were unsure in your first post.

That said, do you have a pic, or can find a pic of the part(s) you omitted when you did the install?

 

On page FSU-9 of the 2012 G37 sedan manual, if you look at the link, there is a washer that goes on the top stud of the link. I used that with the new Moog links that did not come with them.

 

Maybe another better way to describe what I hear/feel when driving is... picture driving your car with your tire pressures at 50psi. Every slight imperfection in the road would be amplified in feel/sound.

 

I would look at other parts since you are certain the bar is tight. Control arms, struts, etc. Maybe the noise was not coming from the sway bar to begin with?

 

I may be on to something. Two things... 1- I just had another look at the FSM and saw the recommended torque specs for the links, and given my contorting act under the car, and admission of not having looked at the specs in advance and not using a torque wrench, I may not have achieved the required spec. 2- there are conflicting torque specs for the links depending on the page you look at in the front suspension section. In all places it shows the lower nut to the sway bar being 62 ft/lbs, but for the upper nut to the lower control arm the spec on some pages it shows 120 ft/lbs whereas other pages show 74 ft/lbs. The 120 ft/lbs seems outrageous given the size of the nut, and considering its the same size nut as the lower that only requires 62 ft/lbs. So I'm taking the 120 ft/lbs as a misprint, and will be getting under the car tonight and cranking them to 62 and 74 respectively.

 

Well that was a waste of time. Got under there and snugged this up (they were pretty much there already), and no difference. Took one off and removed that washer, and no difference. But I'm still convinced I hear/feel it in the bar, at the links. Will eventually get another set of eyes/ears on it. Its subtle, but I'm convinced, shouldn't be there. Thanks for your input.

 

What kind of noise?? Video clip of it?

 

I'm back with an update. I believe I've found the real source of the noise while driving. I found that my calipers have a little wiggle to them and they rattle over bumps. Will start another thread. Thanks to you that contributed on this.

 

The replacement pars I have, Beck/Arnley, also don't have a washer for the top stud. Not sure if I should use the OEM washer or not.

-Eric

 

I doesn't make a difference from a noise point of view, and I don't suppose it makes any difference from a function point of view. Also, I wouldn't use that 120 ft/lbs spec on the upper bolt... it must be a misprint.

 

Agree - that's how I damaged one as the threads stripped. Am planning on 80 ft. lbs. for top and 62 on bottom.

-Eric