Hello,
I have a 2001 Toyota Prius (4cyl. hybrid, CV transmission) with 138,000 miles. I just put 4 new General Altimax RT tires (175/65R14) on it, and the handling is very different. The car seems to dance or jitter just a bit on the road at highway speeds, as though the tires are too responsive. At the same time the tires seem to grip the road very well. The problem is particularly noticeable on grooved or rough pavement. It is close to normal on smooth asphault. It still has the original struts and shocks, and I will get those checked. The previous tires were Michelin Harmony, and the handling seemed normal with those. Are these the wrong tires for this car?
Thanks,
Pat
First check the tyre pressure. Often they over inflate the tyres intentionally and are planning on adjusting it later. They could have missed the last part.
Having different feel is not the same as bad feel. The old worn tyres may have been somewhat like the new tyres when they were new. Now after all those miles, they changed slowly and you did not notice. After checking the tyre pressure (use the pressure on the sticker in the glove box or under the fuel filler lid, not the one on the tyres) if you fell they might not be right, start by taking them back to whoever mounted them.
Did you get them aligned and/or balanced when you bought them?
I agree that the reported symptoms are similar to what would happen with overinflated tires. Check the pressure when the tires are cold (before being driven more than a couple of miles at low speed), and adjust if necessary.
This, in my recent experience, can happen. I just bought two new tires for my VW Golf. The highway steering stability is not what it was before. The handling did get just a bit more stable after the tires had eight thousand miles of wear but are still not what I would like. I certainly do have a tire pressure gauge and an air compressor but have not attempted pressures other than specified to repair the situation.
Balance and alignment are not a factor in my view; it’s the design characteristics of the tires.
The tire pressures are 35 psi front and 33 psi rear as specified in the owners manual. They are Standard Touring All-Season, which is higher performace than the Michelin Harmony, with a 70,000 mile warranty. They got surprisingly good reviews on tirerack.com. They seem to be properly balanced. I do not feel any shaking in the steering. I also had the car aligned when the tires were installed.
The key to solving this puzzle is: “…The problem is particularly noticeable on grooved or rough pavement…”
What you have is commonly called “Groove Wander” or “Tramling” (I prefer the first term - more descriptive!
The cause is the grooves in the road lining up with the grooves in the tire. It is aggravated by overinflation and alignment (toe out really seems to accentuate this.)
As suggested, check the inflation pressure. If that doesn’t solve the problem, then check the alignment. It’s been my experience that most published alignment tolerances are too wide - by about half. If the toe isn’t within the inner half of the spec, then that could be contributing to the problem.
And lastly, the tire. Per Tire Rack’s photo, this tire only has 2 circumferential grooves, so it would be a surprise to find this tire with groove wander problems. So I suspect the real source is somewhere else - the pressure or the alignment.
It’s also possible the problem is nothing more than the new tires having a different feel as compared to the oid tires.
Some people also become acclimated to worn shocks/struts and notice after a shock/strut replacement the ride seems to be “stiffer now”.
(I’m not too keen on General tires anyway after having owned a couple sets of them many years ago (bad handling and premature tire wear)
Actually, my tires only have one circumferential groove. The Altimax has one or two grooves depending on the width.
I had it aligned when the tires were installed, and:
Toe: 0.07/0.07 (range -0.05 - .15)
The tire pressure is 35/33 per the owners manual. If that is wrong for these tires, how do I determine what it should be?
Since we’ve elimnated both the alignment and the pressure, That would leave us with the tire.
And since the tire only has a single groove, I suspect the difference is just the way it feels. You might try a bit more pressure, but under no circumstances try less.
But I don’t think there is anything to worry about - you’ll get used to the difference in feel.