I rotated my wheels after approx. 20,000 miles. I should have done it sooner. I noticed the tread pattern was considerable different when rotated. It has been about 6,000 miles since the rotation but I get high vibration noise when I'm around 30-40 mph is when it is most noticeable. I'm assuming this is probably exacerbated even more due to the harder rubber tires for the Prius. Is this just from not rotating sooner even after 6,000 miles or an actual tire problem ? Has anyone else experienced this ?
Do you see any signs of cupping or other abnormality on the front tires? If so, this can be a cause of vibration. If there is even tread wear you may want to have the tires balanced. Unbalance is the most likely cause for vibration especially at higher speeds. Also my OEM Yokohama tires got progressively more noisy as the tread depth decreased. When they were at 4/32" they were really bad.
If it were me I would have the tires balanced and the alignment checked. They should wear pretty evenly with the fronts wearing a little more quickly due to front wheel drive. If everything is correct you should not need to rotate your tires very often. I rotated my OEM tires (Toyo Proxis) at 10K miles then again at 30K. At 40K they had been on the front and rear for the same number of miles and needed to be replaced, approximately 3/32. When I replaced them (41K miles) they were worn evenly across the tread with a little more wear on the outside due to cornering forces. For my new Michelins I bought a tread depth gauge and I will rotate them when the fronts show several 32nds more wear than the rears. If your tires are bi-directional (I think all OEM Prius tires are) you can rotate them in an X pattern. This may be of questionable value though, the outside will still be on the outside.
Thanks for the replies. There was cupping initially. After about 6,000 miles it has started to diminish. The tread had a cupping pattern because the rear wheels slightly pull when stopping and after 20,000 miles the guy at the dealer said that it created a slight cupping pattern. I'll have the alignment checked however the car does not really shake the steering wheel or veer hard in either direction. The steering wheel feels slightly off center by 1/8-1/4" or so. I will probably have my car realigned next oil change and have the steering wheel recentered. The road noise though in general and vibration is very noticeable at midspeeds. How perfect should the steering wheel and alignment be ?
Steering wheel centering can be right on, if you show them where you want it they can adjust the toe to make that the straight ahead position. 1/4" to an 1/8" isn't to bad but I would have the alignment done, things can be off that cause tire wear and not many other symptoms. If you have it done at least you will know it's correct. I think you should have the tires balanced also. It has been reported on this site that some of the OEM tires had a cupping problem even though balance and alignment were OK. But having those things checked is the only way to tell if they are within specs.
I rotated my tires after 8K miles and found that it created a lot of tire noise--which is more pronounced on a Prius since it is a quiet car. What a nuisance. I endured it for about 1K miles, brought my car back to the dealer last week, and unrotated the tires. My Prius is quiet again. My conclusion: don't rotate tires on a quiet car like the Prius, or any hybrid. Don't waste your money. Wear the tires down and buy a new set.
Even if the tires really don't need rotating every 5K miles like the manual says, you should probably, at minimum, rotate the tires once halfway through their life and make sure the tire balance and wheel alignment are correct.
