20" Wheels Vibrate At 100-120km/h

[Irv]

My new 09 Sierra with the new style 20inch wheels vibrate pretty bad at 100 to 120km's/H, it did it before I had my left front wheel replaced and now it is doing it worse?

 

I noticed with the new wheel, they put 2 huge outside weights on and the passenger side has 1 big one.

Anyone else have similar issues with the new style 20's? If so, was a simple rebalance enough to correct the problem?

 

Also curious why GM puts their weights on the outside of the rim, can they not use inside the rim stick on weights?

[androgelrx]

My new 09 Sierra with the new style 20inch wheels vibrate pretty bad at 100 to 120km's/H, it did it before I had my left front wheel replaced and now it is doing it worse?

 

I noticed with the new wheel, they put 2 huge outside weights on and the passenger side has 1 big one.

Anyone else have similar issues with the new style 20's? If so, was a simple rebalance enough to correct the problem?

 

Also curious why GM puts their weights on the outside of the rim, can they not use inside the rim stick on weights?

 

Sounds like you'll need road forced balancing.

[mtm700]

I second that........request stick on wheel weights.

[2004Yukon]

I second that........request stick on wheel weights.

It's actually more efficient to use weights on the inside and outside if needed, makes the tire easier to balance. With my 20's, I just had a new set of Goodyear LS-2 275x55x20 installed three months ago and I had a terrible highway vibration and "shimmy" that you could see in the steering whl. My previous set of tires were the exact same tire with absolutely no problems so I knew that it had to be in the balancing. It took two different trips back to the tire store to get it right. My whls don't have an outside lip, so it's inside stick-on weights only. If you have a vibration or can see a shimmy in the sterring whl, push to get the tires rebalanced. I second the road force machine if necessary.

[2004Yukon]

Also, my vibration was right in the 55-70mph range.

[Irv]

My new 09 Sierra with the new style 20inch wheels vibrate pretty bad at 100 to 120km's/H, it did it before I had my left front wheel replaced and now it is doing it worse?

 

I noticed with the new wheel, they put 2 huge outside weights on and the passenger side has 1 big one.

Anyone else have similar issues with the new style 20's? If so, was a simple rebalance enough to correct the problem?

 

Also curious why GM puts their weights on the outside of the rim, can they not use inside the rim stick on weights?

 

Sounds like you'll need road forced balancing.

 

 

Thanks guy's!

Can someone please explain what "road force" balancing is, I have never heard of it before?

 

I am debating to take it to a speciality shop only because I don't want to have to do multiple trips to my dealer, which is about 40 km's away? I know it is under warranty but I have no problem paying someone to do it as long as I know it will be done right and they use inside wheel weights.

[androgelrx]

My new 09 Sierra with the new style 20inch wheels vibrate pretty bad at 100 to 120km's/H, it did it before I had my left front wheel replaced and now it is doing it worse?

 

I noticed with the new wheel, they put 2 huge outside weights on and the passenger side has 1 big one.

Anyone else have similar issues with the new style 20's? If so, was a simple rebalance enough to correct the problem?

 

Also curious why GM puts their weights on the outside of the rim, can they not use inside the rim stick on weights?

 

Sounds like you'll need road forced balancing.

 

 

Thanks guy's!

Can someone please explain what "road force" balancing is, I have never heard of it before?

 

I am debating to take it to a speciality shop only because I don't want to have to do multiple trips to my dealer, which is about 40 km's away? I know it is under warranty but I have no problem paying someone to do it as long as I know it will be done right and they use inside wheel weights.

 

 

Here is how a guy on the Toyota forum explains it a while ago:

 

"You have to remove the wheel and tire from the vehicle to have it road force balanced. What the machine does is spin the wheel/tire slowly while pressing a roller against the tread with about 1400 pounds of force. It measures the "loaded runout" of the wheel/tire combination. Then it measures, using other rollers, the runout of the wheel where the bead seats. Then it instructs the user to mark the tire and the wheel, remove them from the machine, break the beads loose, rotate the tires on the wheel to match the marks, then re-inflate and re-mount the wheel/tire on the machine. Then it spins it again to measure the results, then spins it up so balance weights can be applied in the usual manner.

 

OK, now what's it REALLY doing?

 

It models the wheel bead mounting surface as a circle that is not necessarily concentric with the rotational axis of the wheel. For the technically literate, that's the first order radial harmonic. It models the tire as a circle that's not necessarily concentric with its beads. It then computes how to mount the tire on the wheel so that the "high spot" of the tire is at the "low spot" of the wheel. Again for the technically literate, it puts the first order harmonic of the tire out of phase with the first order harmonic of the wheel such that they cancel as much as possible.

 

What that does is minimize the net loaded radial runout of the wheel/tire combination. In layman's terms, it makes the tread surface, under load, as round as possible, relative to the axis of rotation of the wheel.

 

Does it work? Absolutely. Very expensive machines are used to do the same thing with the tires and wheels that are mounted on new vehicles at the factory. The Hunter GSP9700 does it just as well and it does it in a tire shop. Ask Michelin -- their engineers bought the first six of them Hunter produced.

 

You can road force balance wheels at any time. I've done it with my own tires at 50,000+ miles. Tires sometimes change their loaded runout with wear, and road force balancing can improve their performance."

[mtm700]

Warranty will cover road force balancing. We have a machine (Hunter GSP9700) and have no problems what-so-ever getting rid of vibrations using stick on weights and replacing bad tires/rims. The Chevy dealer sends all their trucks to us to cure vibrations with the 20" rims. For the first few years we had the machine, every dealer around was bringing us work. Once they realized the value and importance this machine offered, they all wound up buying their own.

[ShimanoFisherman]

I actually noticed a weird vibration the night I took my truck home. Brought it back in a couple days later so they could install an accessory and told them about it. Turned out, the right rear tire had excessive lateral run-out and they had to replace the tire.

 

I do notice the same weights around the wheel. I'm tempted to take it somewhere and have them use tape weights on the inside as much as possible. I know it can be done, b/c they had to do it with my JGP wheels on another truck.

[Irv]

My new 09 Sierra with the new style 20inch wheels vibrate pretty bad at 100 to 120km's/H, it did it before I had my left front wheel replaced and now it is doing it worse?

 

I noticed with the new wheel, they put 2 huge outside weights on and the passenger side has 1 big one.

Anyone else have similar issues with the new style 20's? If so, was a simple rebalance enough to correct the problem?

 

Also curious why GM puts their weights on the outside of the rim, can they not use inside the rim stick on weights?

 

Sounds like you'll need road forced balancing.

 

 

Thanks guy's!

Can someone please explain what "road force" balancing is, I have never heard of it before?

 

I am debating to take it to a speciality shop only because I don't want to have to do multiple trips to my dealer, which is about 40 km's away? I know it is under warranty but I have no problem paying someone to do it as long as I know it will be done right and they use inside wheel weights.

 

 

Here is how a guy on the Toyota forum explains it a while ago:

 

"You have to remove the wheel and tire from the vehicle to have it road force balanced. What the machine does is spin the wheel/tire slowly while pressing a roller against the tread with about 1400 pounds of force. It measures the "loaded runout" of the wheel/tire combination. Then it measures, using other rollers, the runout of the wheel where the bead seats. Then it instructs the user to mark the tire and the wheel, remove them from the machine, break the beads loose, rotate the tires on the wheel to match the marks, then re-inflate and re-mount the wheel/tire on the machine. Then it spins it again to measure the results, then spins it up so balance weights can be applied in the usual manner.

 

OK, now what's it REALLY doing?

 

It models the wheel bead mounting surface as a circle that is not necessarily concentric with the rotational axis of the wheel. For the technically literate, that's the first order radial harmonic. It models the tire as a circle that's not necessarily concentric with its beads. It then computes how to mount the tire on the wheel so that the "high spot" of the tire is at the "low spot" of the wheel. Again for the technically literate, it puts the first order harmonic of the tire out of phase with the first order harmonic of the wheel such that they cancel as much as possible.

 

What that does is minimize the net loaded radial runout of the wheel/tire combination. In layman's terms, it makes the tread surface, under load, as round as possible, relative to the axis of rotation of the wheel.

 

Does it work? Absolutely. Very expensive machines are used to do the same thing with the tires and wheels that are mounted on new vehicles at the factory. The Hunter GSP9700 does it just as well and it does it in a tire shop. Ask Michelin -- their engineers bought the first six of them Hunter produced.

 

You can road force balance wheels at any time. I've done it with my own tires at 50,000+ miles. Tires sometimes change their loaded runout with wear, and road force balancing can improve their performance."

 

 

Great explanation, thank you for your time typing it up!

 

Thanks for the other replies too, those are great as well.

I will first ask my dealer if they have this machine and if not I will phone around and see if other GM dealerships do,,,, if not, I will be sure to find a tire shop that does.

Any idea what I will be looking at cost wise, I guess they will be based on the severity of the tire/wheel or if they have to do them all?

 

Thanks again guy's, you have all provided me with some great info, I had never heard of a Road Force balance before and I consider myself somewhat of a gear head

[androgelrx]

Last time I had it done on the Lexus at a local shop cost me $40.

[mtm700]

I think we charge around $100.00, techs get 2.0 hours of labor to do it.

[Irv]

I think we charge around $100.00, techs get 2.0 hours of labor to do it.

 

 

I take it that is in American dollars? If so, I would be lucky to get away with $200-$250 up here! I believe shop rate at GM and other dealers is around $90 to $110 dollars an hour, depending where you go?

[mtm700]

If you wind up paying a non-dealer to do this due to no dealer in your area having the balancer, make sure you get all the printouts of what was done. Take them to the dealer and request to be reimbursed. Shouldn't be a problem.

[Irv]

If you wind up paying a non-dealer to do this due to no dealer in your area having the balancer, make sure you get all the printouts of what was done. Take them to the dealer and request to be reimbursed. Shouldn't be a problem.

 

 

Thanks, hopefully that is an avenue I won't have to take but if no GM dealers around have the road force equipment, then I will certainly give it a try.