Intermittent steering wheel wobble at 5-20 mph

[TheBirdistheWord]

I have a strange wobble that is seemingly getting worse, and I can't recreate it at will to try and diagnose It. feels/looks like someone shaking the wheel back and forth an 1/8th turn.  The car drives straight while it's happening, but it also feels like the entire front of the car is rocking back and forth slightly.   

 

I thought it was the (zx front and rear disks) brakes at first, but after inspection the rotors aren't grooved at all and the pad surfaces are in tact and look okay with 80% life left on them. Have T3 gtx2 front hardware, stock steering link and tie rods, with coilovers on ZX struts, and a steering box brace.  

 

I'm just looking for some ideas on where I can start checking for loose stuff beyond the typical yanking on the linkage. 

[demo243]

Could be a number of things- when does it shake? Under braking? Under coasting?

 

Under braking indicates pad material on the rotors or “warped” rotors.

 

While coasting or under acceleration indicates something in the linkage- like worn tie rods.

[demo243]

Check the steering arm to strut bolts - especially if you are running bump steer spacers, if those come loose you will get play that could cause that wobble.

[datzenmike]

Rotor might have high spots which won't be visible as 'groves'. Raise each wheel and spin by hand looking for any tight spots.

 

Lift each front wheel and spin while looking at the tire tread for a bulge or high spot.

 

Idler arm bushings worn???

 

Wheel bearings properly pre loaded? Can you wobble the tire and wheel when off the ground?

 

Tension rod bushings worn or damaged.

 

 

[Crashtd420]

Also tire condition can be a factor....

Are they old or worn?

[TheBirdistheWord]

1 hour ago, demo243 said:

Could be a number of things- when does it shake? Under braking? Under coasting?

 

Under braking indicates pad material on the rotors or “warped” rotors.

 

While coasting or under acceleration indicates something in the linkage- like worn tie rods.

Coasting mainly.  Braking or accelerating doesnt seem to change the condition.   These tie rods are relatively new but I do have the T3 tie rods waiting to go in, this might be the time. 

1 hour ago, demo243 said:

Check the steering arm to strut bolts - especially if you are running bump steer spacers, if those come loose you will get play that could cause that wobble.

Copy that thank you!

12 minutes ago, datzenmike said:

Rotor might have high spots which won't be visible as 'groves'. Raise each wheel and spin by hand looking for any tight spots.

 

Lift each front wheel and spin while looking at the tire tread for a bulge or high spot.

 

Idler arm bushings worn???

 

Wheel bearings properly pre loaded? Can you wobble the tire and wheel when off the ground?

 

Tension rod bushings worn or damaged.

 

 

Idler arm bushing is new, tc rods are heim joints, federal fd2 tires have less than 5k on them.  I will check the other things. Thank you!

[Jesse C.]

Swap out the rims and see what happens, and yes, check the bearings. 

[datzenmike]

New is no guarantee they are good. Lift an spin tires looking at tread for humps or wobble. I had a rear tire develop a lomp the size of my palm and this explained a side to side slow shimmy as you roll to a stop. Rim may also be bent. Tug on all the steering components looking for looseness.

[TheBirdistheWord]

Thread revival. Changed the wheels/tires and had two separate alignments since I posted last.  Seems this problem WAS exacerbated by low tread/out of balance tires but it was not the cause.  While it's not wobbling as violently as it was with old wheels and bald tires, I can feel it "trying" to wobble and I'm guessing the sticky new tires are keeping it from breaking into an all out shake show. 

 

I can now hear an intermittent popping from the driver side while turning either way.  I've double checked the strut mount bolts, tie rod end nuts, and steering gear nut.  

 

what is proper preload procedure for the wheel bearings? There is no play in the wheel on the vertical axis when the car is in the air but I figure I should check this for process of elimination. 

 

Also, how does one check the health or straightness of a steering box/arm?

 

As always, any input is greatly appreciated.

[datzenmike]

Remove the wheel nut and pop the bearing out and inspect it for gross damage. Lube with wheel bearing grease and install.

 

Tighten the wheel nut to 20 ft. lbs.

Spin tire several times in both directions to seat against the new grease.

Check the 20 ft. lbs.

Loosen nut 60 degrees or 1/3 of a turn.

Install cap nut by turning nut to the nearest position where a new cotter pin can be inserted.

 

Lift and spin all the tires by hand looking at the tread for high spots (lumps) or the tread pattern squirming. Even if new tires. Rim may be bent.

 

 

[Stoffregen Motorsports]

Loose or worn control arm bushing, worn out TREs, even a loose crossmember (where it bolts to the body) can all cause death wobble on a 510. I deal with death wobble on 4x4s a lot and in the trucks it's usually not enough caster, combined with worn parts. Tire shape can also exacerbate the issue. I only once had death wobble in a 510, and it turned out to be worn control arm bushings, the rubber ones at the crossmember.

 

EDIT - I forgot to add wheel offset. Too much negative offset in the wheels can cause a jacking effect which can also cause the wobble.

Edited June 28, 2022 by Stoffregen Motorsports

[paradime]

Popping sounds like bearings to me. They're relatively cheep so I'd replace them regardless of not seeing ware. If the wobble continues, try pulling next to a curb until the tire touches so the wheel is held firmly straight. Turn the steering wheel left to right and listen for clunking and or feel a gap in the linkage. If nothing, do the same on the other wheel to be sure. My first 510 had a similar wobble and it was an unevenly warn tires from a missing balancer weight. Good luck and keep us posted.