Re-Torque Thrust Arms Properly?
 

I had my neighbor install new front, upper control arms (thrust arms), because the noise had returned when doing slow speed, sharp turns, as in pulling in or backing out of a parking spot or the driveway. I'm not sure how to describe the sound, sort of a thump or popping sound, and it is more pronounced on uneven surfaces. I had this sound 2 years ago and replacing the thrust arms made it go away. This time, it did not. I gave my neighbor the torque specs and showed him how it called for torqueing the bolt that goes through the bushing after the vehicle is back on the ground, but he said he didn't have any way to get to it after the vehicle was under load. I've got unlimited alignments at Firestone, so he said I might see if they can do it when it is on the alignment rack.

A little more history on my front suspension: As stated, I replaced the upper control arms and ball joints 2 years ago (Lemforder). When the sharp turn sound returned, I turned the wheel all the way and thought I saw cracks in the bushings. I bought the Meyle HD bushings and had them pressed into my original control arms and bought new Meyle ball joints as well. When he removed the Lemforder arms, there doesn't appear to be anything wrong with the bushings, but they were also torqued with it in the air 2 years ago.

About a year ago, I had other sounds on slight turns on uneven surfaces and vibration in the pedal when braking at ~ 50 mph, so I replaced the lower control arms and sway bar end links (Lemforder) and that seemed to take care of that.

About a month ago, when the sharp turn noise returned, I had him install new tie rods (Lemforder), but that didn't take care of the noise, and I still have a slight vibration in the pedal when braking. I had read about others with short life on their Lemforder thrust arms, so I figured it had to be that, and the sound was getting worse. The CV axle boots are fully intact on both ends and the sound doesn't appear to be CV joint related (I had that on another car a while back and know what that feels like).

I'm not sure if Firestone will want to re-torque these for me. If not, I may try to go to the DIY garage and do it myself on their drive up lift. Thanks for reading along - here are my questions:


*Do you think loosening the bushing bolt and re-torqueing it properly under load could fix this?


*Would I want to jack it up before loosening it or just loosen it under load, bounce it, then re-torque to 122 ft lbs?


*Does the splash shield or anything else need to be removed to get to this bolt, or are there any other tricks to getting a large torque wrench to this bolt?

Do you have ramps? That's what I use. Roll the car up on the ramps. The suspension is under load and you have access to the bolts. The splash shield needs to come off.

Your vibration could be coming from your lower control arms. How old are those?

That popping noise could also be worn sway bar links. I read somewhere you can tape them real tight with electrical tape and then drive it. If the popping noise goes away you have your culprit. Taping them isn't a fix it's just a way to test them.

I replaced the other control arms and sway bar links last summer.

I don't have ramps, but I can go to the DIY garage and put it on a drive up rack (where it would be under load). Do I need to jack it up to loosen the bolts or can I just loosen them while it is under load?

If they were torqued with the car in the air (no load) then used for a period, the bushes will be shot. Re-torquing them now won't change that. :-(

Torquing the bushes with no load creates a twisting offset on the bushes when the load is applied and this destroys them pretty quickly.

It was just a couple of days ago. Also, the ones that were installed this way 2 years ago and were removed the other day don't seem to have any cracks in the bushing rubber material.

If you drove it for a few days and not a long distance, you're ok. Just loosen the bolts when the vehicle is jacked up. Loosen until just snag. Drive it up the rack and tighten to recommended torque spec. Remember, sway bar links don't require loading to tighten. Control arms only require the subframe connections (inner connections) to be tightened under load.

Yeah, two days won't hurt them. :-)

BTW, the sound you describe doesn't sound like control arm bushing failure - which is normally a clunk when you dab the brakes. Odd sounds when turning at full lock could be the alloy reinforcement plate perhaps? Maybe check the torque on the six plate bolts (and no, we don't want to discuss the merits of replacing these bolts! ;) )

I do sometimes get a clunk when I press the brakes before taking it out of park, or before switching from R to D, etc..

Have never had the plate off. Judging by all of the maint records from the PO, they didn't either unless you need to remove it to replace transmission cooler lines. I want to take it off soon so I can change front differential fluid... There are no cracks in it or anything like that.

Also, did you do the sway bar bushings when you did the links? I experienced similar on a different car with new links and new everything else, new bar bushings happened to fix it.

Have not done the sway bar bushings. Will have to look into that.

Before, I read others said the full stop turn clunking was the thrust arms normally. Two years ago, mine definitely had cracked bushings and replacing them definitely got rid of the noise for a while.