All new suspension for steering shake

[dlink]

So I’ve officially lost my mind from this steering wheel shake that I’ve lived with for 1.5 years on my 45th anniversary LS3 car and basically decided to replace the entire suspension (almost). One day around 75k miles I had my car aligned and new tires mounted and balanced at a tire choice & since then it has had a steering wheel shake under acceleration/cruising between 50-80mph and even more vibration when braking at those speeds. At first I blamed the tires and had sent them back and got a new set of Firestone firehawk indy 500’s but didn’t get better. Had them re balance the tires I’m not kidding 6 different times between 2 of their shops including road force, still shaking steering wheel at 50-80. First thing I did was change my front rotors and pads, no change. Chevy charged me $400 to tell me it was the center support bearing. I changed the entire driveshaft, center support bearing and giubos, no change.

The car is on stock suspension with BMR lowering springs installed since about 10k miles. Car now has 95k miles and is turning 13 years old with a notably weak driver side shock / spring and as of the last thousand miles or so a clunk has developed in the passenger rear when going over bumps / turning to park.
Figured I’d share what I’m installing now to upgrade my old suspension and (hopefully) fix my problem for anyone in the same boat.

Pedders extreme XA coilovers
Pedders sportsryder front & rear adj. sway bars
Pedders rear subframe bushings poly inserts
Pedders rear sway bar end links
Detroit speed HD front sway bar end links
BMR non adjustable toe rods
BMR trail arms
BMR poly trail arm knuckle bushings
BMR rear upper control arm poly bushings
BMR front radius rod poly bushings
Moog upper & lower front control arms
Moog inner / outer tie rods
Indy 500 ultra performance summer street tires

I’m also replacing my original fluids for:
Redline D4 ATF transmission fluid
ACDelco LS Differential fluid (OEM)
Motul RBF 600 DOT4 Brake fluid
ACDelco Radiator fluid (OEM)

And have already changed out Injectors, spark plugs, wires and coil packs. Going to seafoam spray the intake, clean the MAF sensor & clean out my air intake filter, clean the engine bay and install a new air cabin filter.

Did I miss anything? Thinking it should more or less feel like a completely different car once I’m done.

[gtstorey]

Warped/Bent Wheel?

[dlink]

Originally Posted by gtstorey

Warped/Bent Wheel?

Well we put the car up on a lift and spun all 4 corners, none looked loose / wobbly from what we could tell however don’t recall if we checked the inside of the wheels while spinning potentially we only looked at the outside. You think a bent / warped wheel you’d feel only at mid - high speed and not consistently at any speed range?

[KillboyPowerhead]

Could swap wheels front to back and see if anything feels different.

[Mr_Draco]

Originally Posted by dlink

Well we put the car up on a lift and spun all 4 corners, none looked loose / wobbly from what we could tell however don’t recall if we checked the inside of the wheels while spinning potentially we only looked at the outside. You think a bent / warped wheel you’d feel only at mid - high speed and not consistently at any speed range?

Possibility.

Many many years ago a member had the same issues but couldn't find it. Come to find out it was a rim that was just slightly out of round. They was brand new aftermarket rims. It wasn't noticeable by hand spinning the wheels, they had to spin at driving speeds. The only reason I remember this is because he made a post about breaking his finger while trying to stop the rim from spinning .

[dlink]

Originally Posted by Mr_Draco

Possibility.

Many many years ago a member had the same issues but couldn't find it. Come to find out it was a rim that was just slightly out of round. They was brand new aftermarket rims. It wasn't noticeable by hand spinning the wheels, they had to spin at driving speeds. The only reason I remember this is because he made a post about breaking his finger while trying to stop the rim from spinning .

Well I guess if after the suspension work the issue persists I would have to consider the wheel hub being out of balance or a distortion in a wheel.

Something else worth mentioning is when coming to a stop at a light, it feels like the car shimmies back and forth slowly until I come to a stop which seems potentially suspension related. I know for a fact my spring / shock on driver side front is very weak. Radius rod bushing maybe? Seen that bushing can cause issues on our chassis G8’s.

[dlink]

Originally Posted by KillboyPowerhead

Could swap wheels front to back and see if anything feels different.

Staggered setup

[SummitWhite11]

Originally Posted by dlink

So I’ve officially lost my mind from this steering wheel shake that I’ve lived with for 1.5 years on my 45th anniversary LS3 car and basically decided to replace the entire suspension (almost). One day around 75k miles I had my car aligned and new tires mounted and balanced at a tire choice & since then it has had a steering wheel shake under acceleration/cruising between 50-80mph and even more vibration when braking at those speeds. At first I blamed the tires and had sent them back and got a new set of Firestone firehawk indy 500’s but didn’t get better. Had them re balance the tires I’m not kidding 6 different times between 2 of their shops including road force, still shaking steering wheel at 50-80. First thing I did was change my front rotors and pads, no change. Chevy charged me $400 to tell me it was the center support bearing. I changed the entire driveshaft, center support bearing and giubos, no change.

The car is on stock suspension with BMR lowering springs installed since about 10k miles. Car now has 95k miles and is turning 13 years old with a notably weak driver side shock / spring and as of the last thousand miles or so a clunk has developed in the passenger rear when going over bumps / turning to park.
Figured I’d share what I’m installing now to upgrade my old suspension and (hopefully) fix my problem for anyone in the same boat.

Pedders extreme XA coilovers
Pedders sportsryder front & rear adj. sway bars
Pedders rear subframe bushings poly inserts
Pedders rear sway bar end links
Detroit speed HD front sway bar end links
BMR non adjustable toe rods
BMR trail arms
BMR poly trail arm knuckle bushings
BMR front radius rod poly bushings
Moog upper & lower front control arms
Moog inner / outer tie rods
Indy 500 ultra performance summer street tires

I’m also replacing my original fluids for:
Redline D4 ATF transmission fluid
ACDelco LS Differential fluid (OEM)
Motul RBF 600 DOT4 Brake fluid
ACDelco Radiator fluid (OEM)

And have already changed out Injectors, spark plugs, wires and coil packs. Going to seafoam spray the intake, clean the MAF sensor & clean out my air intake filter, clean the engine bay and install a new air cabin filter.

Did I miss anything? Thinking it should more or less feel like a completely different car once I’m done.

Something must've happened at the tire shop when you had your new tires installed and the alignment done... Especially if there was no noticeable problem before you had it serviced.

[dlink]

Originally Posted by SummitWhite11

Something must've happened at the tire shop when you had your new tires installed and the alignment done... Especially if there was no noticeable problem before you had it serviced.

Agreed, just don’t know what exactly. I haven’t taken it anywhere since to get it realigned but both shops said the alignment was good. Each time they’d rebalance the wheels there would be different amount of of weights in different spots. It just seemed to me that an alignment wouldn’t cause all the vibration & ruled out in my head a bad tire balance since I had rebalanced 6 times.

[1JEWLDSSRS]

I'm thinking you might have a slightly bent/warped wheel, or one of them isn't seated properly on the hub causing it to wobble. Hence the shimmying back and forth when coming to a stop. Are you running any spacers with the wheels? I had some on my mustang back when, and they were not completely flat, and would make the car do the same thing. Finally I just took them off. You can check your wheels on a high speed spin balancer without the tires on them, that would let you see the wheel in its entirety whild spinning. Just something to consider from past experiences.

[dlink]

Originally Posted by 1JEWLDSSRS

I'm thinking you might have a slightly bent/warped wheel, or one of them isn't seated properly on the hub causing it to wobble. Hence the shimmying back and forth when coming to a stop. Are you running any spacers with the wheels? I had some on my mustang back when, and they were not completely flat, and would make the car do the same thing. Finally I just took them off. You can check your wheels on a high speed spin balancer without the tires on them, that would let you see the wheel in its entirety whild spinning. Just something to consider from past experiences.

Certainly is a possibility, we did spin all 4 and put a straight edge against the outside of the wheel as they were spinning and we didn’t see any unordinary movement. If all this suspension work doesn’t fix the issue I’ve basically narrowed it down to wheels, wheel hub, rack & pinion or brake caliper(s).

I just took a look at Tirerack to see what kind of wheels they offer… think I’ll have to stick with searching for a replacement 45th anniversary set.. best looking option on my car imo especially for the $.

[1JEWLDSSRS]

Originally Posted by dlink

Certainly is a possibility, we did spin all 4 and put a straight edge against the outside of the wheel as they were spinning and we didn’t see any unordinary movement. If all this suspension work doesn’t fix the issue I’ve basically narrowed it down to wheels, wheel hub, rack & pinion or brake caliper(s).

I just took a look at Tirerack to see what kind of wheels they offer… think I’ll have to stick with searching for a replacement 45th anniversary set.. best looking option on my car imo especially for the $.

Well here's hoping you get it figured out. That would really bother me! Good luck with it.

[dlink]

Originally Posted by 1JEWLDSSRS

Well here's hoping you get it figured out. That would really bother me! Good luck with it.

Thank you! Since we were talking about it I checked it out and found a guy local to me selling 45th wheels for just $200 for the set….. think I may have to grab that deal in case I do have a warped wheel.

[SummitWhite11]

Originally Posted by dlink

Thank you! Since we were talking about it I checked it out and found a guy local to me selling 45th wheels for just $200 for the set….. think I may have to grab that deal in case I do have a warped wheel.

Now that's a steal!