Failed Wheel Balance

Has anyone else had the Hunter balancer fail their rims for balancing?

My dealer's mechanic showed me that the two rims he tested rotated out of "true". This is where the rim moves up and down on the vertical axis, but is perfectly "true" on the horizontal and was easily visible to the untrained eye.

I hate to drive the car, as the high frequency vibration hurts my hands, and causes them to numb out. I have had the dealer balance the tires twice before, and suspect that this problem existed previously, but their equipment could not detect it. I am concerned that I will get tire failures if allowed to wear in this unbalanced state.

Does anyone have a solution? I am about ready to buy my own rims and then bill Mazda?

 

When I bought my new wheels I had them mounted at a shop that used a Hunter GSP9700. After hearing all of the hype I figured that they wouldn't have any problems balancing the wheels with the tire pressure sensors.

They tried balancing them twice but the wheels would always start shaking around 70 MPH. I even brought in the Mazda balancing instructions but it didn't help.

In the end, I brought the car back to the dealership. They have an antiquated wheel balancer and where able to get everything spinning smoothly by following the instructions to the letter.

 

My problem appears to be that the drilling for the center hub hole that is used by wheel balancers is not centered. This causes the wheel to move up and down during rotation in the vertical plane. This lack of concentric drilling simulates out of balance shaking when in fact the Tire is perfectly balanced to the off center axis.

I plan on asking the dealer to replace the rims with properly aligned center hubs, this way I will not have trouble at some future point. These rims will wear out my tires prematurely.

So far my dealer has not returned my call to the Mazda Service Manager.

 

Are all of your wheels experiencing this problem? Ifso I would start to doubt the accuracy of the machine. I can see one wheel and possibly a second doing this but not all four. That violates the rules of probability (don't ask!). I would say there is a problem with the machine and not your wheels. Have him try a wheel of a car in stock, if that one is out of round then the dealer has a defective machine or he is not following the balancing instructions as outlined in the factory service manual.

The instructions have you use a calculation for placement and size of the weight. The tire may be in balance but the mass of the TPMS sensors will affect the CG (Center of Gravity) of the wheel making it seem like an out-of-round condition.

I have Speed Racer to thank for this as I ran into this problem back when I had my new tires installed. It does not matter what machine they are using. All those bells and whistles don't mean diddly squat if the operator is not following the directions correctly.

On an aside we do this all the time when figuring out CG during acft weight and balancing procedures. It is refered to "moment" and "arm". Moment is the weight and arm is the distance from the acft CG. as weight is placed farther out on the "arm" the CG will shift out towards the added weight and polar moment of inertia will increase due to Pendulum effect.

This has a very significant affect on the flight of the acft as many an acft has crached because of fuel being used up shifting the CG of the acft and causing the plane to be unstable. If this is not corrected by moving fuel from one tank to another to rebalance the plane it may cause a crash. The same goes for placement of cargo in the hold of the plane. Same thing the cargo is weighted and placed in strategic areas to even out the plane.

 

I just measured my wheels three times and found that the spacing from the lug nuts to the center bevel used for the wheel balancing is off by .001 to .0015" from being centered. The spacing of the lugs to the bevel used to balance the wheels is not the same. (symetrical)

I would ask that anyone else experiencing a balance problem or cupping of tires check the lug center spacing. I used one of my quality control tools accurate to 1/1000th of an inch to measure the spacing from the outside edge of the lug acorn. All acorns measured identical diameters in the "plane" used to measure the center spacing. If the lugs were drilled off center then the wheels would bounce down the highway no matter how good the balance. Balance will not improve an off center rotation.

When I go to the dealer on Wednesday - Thursday this week I plan on checking the rear wheels while the car is on the stand where the engine can rotate them in mid air, this should reproduce the same visual cue the balance operator and I noted when the last balance effort was aborted on the machine.

When the rim is off the car I should be able to get a better measurement of the actual hole to center bevel of the rim. I will bring my caliper with me to check the inside measurements.

(Center bevel is the lip which stops the mazda emblem from pushing all the way in. It is also the highest edge to make contact with the conical centering adapter used to mount the rims.)

My dealer appears to have the best balancer, however, I am not excited about multipliers being used to change the machines weight predictions. I think it is far more basic than that.

 

Brian the only proven way to check for an out of round condition is by using a run out gauge on the bead of the rim.

Check out some of these sites

Tire and wheel balancing

 

My concern is that the Radial imbalance is automatically corrected when the rim is installed on the balancer. This is fine for the machine, but I think my center of rotation using the lug mounting holes is bad.

Here is the Hunter link explaining the balancer's feature I am concerned about:

http://128.242.141.111/pub/features/how-4.cfm

If the operator installs the tire for true rotation and then installs it with the lugs in a radial imbalance rotation, then I still have a problem which this wonderful machine has failed to correct in three attempts. Remember "Sensitivity of a vehicle to vibration from radial run-out is four to eight times that of wobble from lateral run-out." Think of it as riding on 4 pogo sticks that are out of sync with each other.

I checked another rim and found it to be worse, similar to the first, but now the scale is 1/100th! 10 to 15 hundreths out of round, now that is serious.

I am a very technical person, and fully appreciate the difference a few thousandths can make in how a machine operates and how long it's components live. As an Apache repair person I know that you can appreciate what I mean.

I am about ready to buy my own wheels, but my research indicates that it is money poorly spent at this time. If my rims prove to be defective, I plan on kicking in a few bucks to upgrade them to aftermarket rims where the problem may be taken care of.

Thanks for the input. This is my second Rotary, and I absolutely loved my 7, 98,000 miles and it still used only 1/2 quart of oil per 5,000 mile oil change! If not for rust I would still have her, 4 sets of tires, and a clutch at 90,000 miles. So quiet most people thought the engine had stalled while it was still running! Smoooooth as silk.:D

 

Technicaly radial balance or concentricity is not determined by the lug nuts but by the hub centering ring on the wheel mating with the flange on the brake rotor hub. This is why you need to check run out while the wheel is on the car.

 

Smooth as a baby's butt even after I hit that damn curb. (Can I say damn?)

 

You need to follow Rotary Nut's instructions and check for rim runout on the car. Totally clean the mounting surface to the hub, TORQUE the wheel nuts on, and measure lateral and radial runout on both sides of the rim with a dial gauge. You will have to ask the dealer for specs, but I think you will be surprised - cars have much looser tolerances than helicopters. A 15 thou runout could quite possibly be remedied by wheel balancing...

 

I agree that more measurements are required while the rims are on the car. That is why I plan on being there when the measurements are made.

Does anyone know of a place that balances the tires while they are on the car? This would take everything into consideration.

I do not want a tire that has 10 to 15 hundreths of concentricity error balanced out of it. You can not take up that amount of movement with weights. The rubber or shocks would have to move that much each rotation and I prefer to live without the wear associated with it. The rims should rotate on the car without any "visible to the naked eye concentricity". If it is readily apparent to anyone, then it needs to be fixed. I can not stand to drive a vehicle with unbalanced feeling tires. I would like to get more than 10,000 miles out of the factory tires. I rotate my tires every 5,000 miles and have them check/balance each time. This may be why my tires are not cupped as another member ended up. I think the problem is in the rim not the TPSM which nothing more than a static weight problem easily corrected by any balancer. If the rims are defective, we can not use a rim from a new vehicle on the lot to check the machine. My measurements have indicated a very viable explanation for the axial woes I am feeling. I will test my hypothesis on the car at the dealer. I don't need any special tools, just a simple tape mesure. I will set it to contact the rim at any vertical point, then rotate the tire by hand, if the rim is out of radial alignment, it will show up. I don't need to know any numbers, I just need to show that all the rims have this problem. The axial alignment (left to right wobble) was perfect. The up and down was not.

 

The radial runout spec for the 8 wheels is 1.5mm (0.059"), and the lateral runout spec is 2.0mm (0.078"). Way over 15 thou...

If the wheels are out of spec the dealer will have to put lots of wheels weights on them to balance them. This of course, is not good. As a rule I try to put no more than 25g on any one rim (inner or outer). If any more than that is necessary then I spin the tire around 45 degrees on the rim. Did your dealer try this?

I can't believe that they could not balance the tires properly, and moreso that they are not specific about why. If the wheel is out of spec they should order you a new one, if the tire is wobbly they could still try swapping tires and rims. Tell them to balance your wheels whatever it takes! That's what warranty is for!

 

I worked for Sun Electric and Snap-Tools aka Snap-On-Sun Tech Systems. My Job??? Field Engineer, I repaired Wheel balancers, Engine Analyzers, Freon Machines, battery Testers, You name it. I also trained the grease monkeys errrr Mechanics errr Automotive Technicians on how to USE the Equipment.

They do have a wheel adapter that you actuall BOLT the wheel on to a HUB that is attached perfectly and correctly to the machine and is as accurate as the wheel being mounted on the vehicle and that will balance the wheel. Now that last thing I want to hear is BS about how the hole is not centered on the RIM., that is absolute BS. Cut and dried, did they tell you it was the MUFFLER BEARING causing the wheel to vibrate??,

I just heard something from my brillant brother who can't change a tire ., he had a mechanic tell him the catalytic converter on his car affect how the Brakes operates, and that if the catalytic converter is going out it affects the brakes!!! hahahah and dipshit believes him, and einstein is a republican, go figure, NOT! he is an ostrich with his head in the sand, hide your head from the truth, it stays the same!

The wheel or tire is defective, replace it and then see ,, Under warranty,

this is what happens when FORD's Bean counters stick their greedy hands into the engineering budget of mazda and forces them to use substandard parts, and we the consumer takes it in the ***, replacing those substandard parts AFTER the warranty expires!!

 

I had some major issues with wheels on my previous car which was a 2003 BMW 330i . . . it drove me crazy and no matter how many times I had the tires balanced on the Hunter, it never seemed smooth. BTW This was when I put aftermarket 18" wheels on my car to replace my factory 17's

My wife's Volvo XC90 with 18" tires came brand new with what felt like tires out of balance, after having them balanced at least 2 to 3 times on a hunter balancer I finally gave up and decided to live with it.

To my shocking surprise the car at around 5,000 miles became very smooth and the vibration was gone, now at almost 9000 miles it is smooth as glass. I ended up figuring out it must have been the drivetrain breaking in because as time went on the truck got smoother.

For you, one other possible solution might be that the tires are now balanced correctly but since you have been riding on unbalanced tires the tires were broken in unbalanced, in 1000 or so miles when the rubber re-breaks in with the newly balanced tire it will smooth out. I have found 18" tires and wheels are VERY sensitive to balancing


One other thing, my RX8 came with what what felt like unbalanced tires and the noise they made at 70mph actually hurt my ears, it sounded like a helicopter was in my car ... now with 2500 miles the car is much smoother now and I dont' get that affect . . .

 

I've been posting about my problem too but have no solutions.

When the dealer rotated my tires they were obviously noisier. Since then the noise, whine and thumping is almost unbearable. The dealer has checked alignment and balanced all of the tires but the problem remains. We spun the tires and can note a certain amount of tire movement (not wheel) our of perfect. THe dealer used his fancy laser reading machine to check tire roadforce and all 4 tires passed. Ideas?

 

You need to have the tires rotated on the rim, unmount the tire from the rim and remount 180 degrees from the original mount. It does work....if the tire is bad or out of round replace it, under warranty, yes We all seem to forget that the OEM times that come on ALL cars are cheap tires, and last maybe one year. Get some better dunlops, or yokohama or pirellis or kumholes the korean tires arent too bad,

 

my stock rims were smooth like butter, and my aftermarket rims and tires are also just as smooth.