Tire/Wheel Balancing

<div class='quotetop'>QUOTE(EssD\";p=\"58496)</div>

I'm confident that every tire shop you visit will spin balance your tires off the car. I think many years ago you could get your tires balanced on the car but I don't think that is done any longer.

 

The computerized spin balance machines, such as the Hunter GSP9700 have been around for at least a decade and a half.

These are better than spinning the tires on the car since the machines tell the technician where to place the weights on both the inner and outer rims.

 

Not all shops spin balance.

Some still "Static Balance" which basically means the wheel is on a gimbel and they add weights til it's level.

But, either way, it's not done on the car.

Go for spin balancing, it's far superior, and make sure they run it up past 55 mph. If they only run it up to relatively low speeds, you can still have a wobble at higher speeds.

 

<div class='quotetop'>QUOTE(Tempus\";p=\"58516)</div>

Stay away from shops that do not have up to date equipment. You will be the one that pays at the end.

 

your looking for a dynamic balance not a static balance. As for the on car spin the last time I saw that was in 1967 after that we went to the dynamic balancer, Bear twin post, It was really good you could actually do a set of 16" duals together just like they would be on the vehicle and you could spin to actual road speed of 85 miles an hour, then just trim the position of the weights till all the jiggle was gone. I'd love to find one of them now as I'd buy it and mount in in my car port and do the odd balance job, for extra cash.

 

just pull the rotors and dynamically balance them as well. That was the advantage of the twin post balancer we had. On my camper truck ( one ton dually ) I pulled the front rotors and spun them. If I do recall right one was on and the other needed 2 ounces and what you do is add weight in the fins. Some of the guys I worked with drill the off side but I found it simpler to just add to the fins. Never had it come out, luck probably.

 

Some HD tire shops have a special dynamic balancer that actually forces the tire against a roller and applies pressure, typical of loaded weights at highway speeds.

I'm not sure if this equipment can be used for car-size tires. It apparently works wonders for HD trucks.

I recall seeing the ad in an older Trailer Life that featured replacing the factory tires/wheels on HD 3/4 ton and 1 ton trucks with line haul tires/wheels. Will try to fiind that ad and give you the URL.

 

You can find "match" balancing equipment at Hunter:

http://www.hunter.com/pub/product/balancer...5115T/index.htm

Hunter also has a simulated "road force" machine at:

http://www.hunter.com/pub/product/balancer/index.htm

As Frank mentioned, if you have an axle shaft or rotor out of balance, you will still have vibration.

 

The front rotors, and the rear drums, are dynamically balanced after they are fully machined. There is no need to balance them further, and unless you have a very sophisticated machine for micro-balancing and can accurately mill balance, you would do more damage than good if you actually found a balance issue. I can assure you that you will not.

 

This is really an issue for gen I or non-preloaded taper bearings. The Prius uses Gen III preloaded integral roller bearings and "loading" the bearing will not change its balance characteristics as there is no end play what so ever. Further, the hubs are already precision balanced during manufacture and assembly.