For 3 years ive owned my 85 cheby K20, I have been plauged with a bad shaking/ vibration at highway speeds. I have run 3 sets of tires each being balanced at least 3 times each, still the problem exists. It aggrivated me enough that this is what instigated buying my 93 CTW, I kept it for a spare. I finally talk to this guy who tells me that that vin of Cheby PU had serious brake drum issues, balance to be specific. so I buy two new drums for the rear and slap them on, holy sheet ,it shook so bad I couldent see straight doing 60 mph. I put on a floor jack under the pumpkin and run it up to 70, aimed it at a big oak tree just in case, and began eliminating parts until the shake was gone. ended up with 1 factory drum and 1 of the newbies. although I found info on balancing drums on the net ,all my local shops think im crazy asking for the service of balancing drums. The truck rides like a Caddy now. If I could just find a CTD to shove in it!!!!!!! ;D

 

Try and find a tire store that has the old fashioned type of wheel balancing. The one where they attach a doodad to the front door and spin each wheel up to speed and balance the rim/tire/brakes as an assembly. This has always cured any balancing problems I have had and the difference is truly amazing. Just remember, if you do this and then later remove a wheel to mark how it came off so that you can reinstall it the same way it came off. If you rotate wheels you have to rebalance everything.

 

In these parts not many shops have them but, I thing I might be able to locate somebody, am concerned reguarding the fact that my Cheby has a factory rear locker in the corp 14 bolt diff. The build sheet does not specify which type although Im pretty sure its a clutch type. When jacked up and if you spin one wheel the opposite still spins the other direction, i have never tried to hold it while spinning one side only. I know the locker works though, iIjust tested it while it was jacked up on one wheel only and it would drive off the jack. im afraid to damage it or??? spinning one side at speed.

Thanks, Apache.

 

You will not damage it. The balancing speed is not that high. Just imagine what happens when you have one wheel on a slippery surface and the other with good traction. Is this not the same as jacking up one wheel? Just warn the shop to chock the vehicle extra well. It may cause them a slight problem but if they are careful I don't see why it should not work OK. If it is a problem they may be able to jack up both rear wheels and then try and figure out where the vibration is coming from. In that case suggest to them to attach their doodad to each wheel well instead of the door and try it that way.