[WardL]

Thanks for the suggestions. I'll work on the front wheels on-the-vehicle spin balance. I think I can really tell the rear wheels are smoother riding since they were balanced. This is a shimmy and not a shake. The shimmy seems to come from the front of the Cobra causing the steering wheel to move back and forth very quickly. Wonder if the rears will fit up front if I don't turn sharply? The tires are 335/35 ZR 17 and 275/40 ZR 17. I would do this to check if the rear tires are any smoother than the rear. When I bought the Cobra (used) the front was too low and the tires would scrape on the body. If the fronts have balance issues, the scraping could be a cause.