vibration

[diegokid]

After taking the tires to Andy for the road force balance the culprit was found. This balancer assigns a tire a number depending on how much force it takes to make the tire spin without vibration. I was told that a good tire for a car should be 6 - 9. The tire I had that was .090 out of round had a road force of 48! He laughed and told me that he has seen mud tires for 4WD trucks with numbers not that bad. The machine then found the high spot/low spot of tire and rim. These marks were where I had marked them using the dial indicator. The tire beads were broken and the tire moved on the rim and rechecked. Best we could get out of that tire was a 31. He said it would help but may not clear it up, he recommended replacing it, no he doesn't sell tires. The other BFG scored a 13, the two Kuhmo's on the rear scored a 5 and a 6. Suprisingly he told me that tires that fell in the 9 or less range could actually be a little out of balance and still roll without vibration.

Its a sigh of relief and was actually glad it was a tire because after checking drive shafts, axles, rotors ect and the way the vibration was acting the tire was my last try. I just didn't want to believe that a tire with less than 750 miles was bad. Another interesting note was after writing this down in my log yesterday I found where I had checked this before tearing the car down for paint. The reading then was .120 @ 32 PSI vs .090 @28 so the extra PSI must have an affect.

On the upside this gives an excuse to buy a new set tires instead of just one, that way I can have spares! So who has the best deals on the Shelby rims and has anyone tried the Mickey Thompson Sportsman S/R Radial ?