how can i simulate wheel speed with my front wheels to see if my rotors are out of balance? ive road force balanced and conventional balanced 3 times,balanced driveshaft , new shocks, and steering links. only thing left is rotors. its definately in front.

 

have rotors turned , like $10.00 i'd just do it , check your wheel bearings while you have them off .

 

Have you done a run out check of all four wheels while on the truck, Side wall & tread face??
I would think you would have an out of balance rotor, but a bent wheel, or axle. or even a front u-joints ,or carrier bearing if it has the 3 piece drive line. And lastly go to a different tire shop to get balancing done. If a shops balance machine is off balance by even by as little as 1+oz your tires will still be off. Most vehicle this may not be noticed but the bigger tire the more noticeable. Also how big are your tires and how old and type load rating??
orich

 

3 different shops did the balancing. the tires are new 25 70 15.wheel bearings are new.i wanted to simulate front tire speed to see whats going on. ive done the back and all seems smooth.the vibration is at 43 mph dead on everytime then comes back at higher speeds.ive swapped front to back side to side no change. the rotors are omly thing left and even their new. i did a disc brake swap several years ago but the truck sat off and on for 2 years while i worked on it. so im not real sure when this developed. i think i will have them turned just to see what developes even though they dont need it. the rotors are wagner and they are smooth during braking.

 

FLN, The only thing that I can suggest ; Take it to a truck or motorhome shop that can spin balance "on the vehicle". This will prove if it is a tire and or rotor balance. Kenny Nunez

 

I'd lookfor a shop that still does old spin wheel balancing then. They run each tire up and balance the whole rotor/drum,axle/tire at one time. Static balancing Not many shops around these days. So do a search in your state. what ever that is..orich

 

Now I'm assume you had the front end alignment checked after you completed the conversion to disc-brakes? If not then you should get it checked... my 2cents
orich

 

yeah i had front end aligned. I didnt think you could get tires balanced on the vehicle. that would definately be the way to go. whats it call? static?

 

Static balance

Static balance can be measured by a static balancing machine where the tire is placed in its vertical axis on a non-rotating spindle tool. The spot on the tire with the greatest mass is acted upon by gravity to deflect the tooling downward. The amount of deflection indicates the magnitude of the unbalance. The angle of the deflection indicates the angular location of the unbalance. In tire manufacturing factories, static balancers operate by use of sensors mounted to the spindle assembly. In tire retail shops, static balancers are usually non-rotating bubble balancers, where the magnitude and angle of the unbalance is observed by looking at the center bubble in an oil-filled glass sighting gauge. While some very small shops which lack specialized machines still do this process, they have been largely replaced in larger shops with machines