Michelin Hydroedge tires

The tirerack.com site says 11/32 for the hydroedge. Should be the same all the way across I would think. IMHO the difference you are seeing isn't enough to worry about. The higher pressure (42/40) should not cause any more wear in the center than it does on the outside. With bias ply tires it did but the radials we have today don't seem to do that.

However one thing that will cause more wear on certain parts of the tire is alignment. If you have not done so I would suggest having a 4 wheel alignment. It's a lot cheaper than tires and if your car is less than a year old Toyota may do it for free.




edit: Ops, I see your car is more than a year old but an alignment should only cost $70 or so.

 

<div class='quotetop'>QUOTE(tumbleweed @ Jul 26 2006, 06:52 PM) [snapback]292818[/snapback]</div>

Over inflating a tire will cause wear just as much as it being out of alignment. Just in different spots of the tire. Usually an overinflated tire will wear alot in the center.

 

<div class='quotetop'>QUOTE(tmorrowus @ Jul 26 2006, 04:47 PM) [snapback]292780[/snapback]</div>

I have not measured the tires, I have 20,000 miles on my Hydroedge tires. I have bumped the pressure a little bit to 37/35 recently. I was hesitant because the sidewall notes a 35 PSI maximum.

 

<div class='quotetop'>QUOTE(jfschultz @ Jul 27 2006, 08:18 AM) [snapback]293105[/snapback]</div>

Then you must have a different size. The standard for Prius has a 44 PSI maximum.

 

The tire PSI on the sidewall is the maximum amount of PSI for that tire. That doesnt mean you should run that all the time because it wears the tires down faster. Anything higher than the 44 can create an explosion hazard, that is why Michelin put that on the tire, just like the many other brands. Also max PSI depends on load of a tire as well.

 

I think modern tires do not wear faster in the center when they have higher pressure in them as long as the maximum on the sidewall is not exceeded. There have been a lot of posts from people here who noticed the edges wearing faster even when the tires had spent their lives inflated to 42 pounds cold. Mine have worn evenly both on the Prius and my Accord despite having them at 42 or 44 pounds.

Bias ply tires were about the same strength all the way around from bead to bead and when the air pressure increased they tended to deform and bulge a bit in the center of the tread. This caused the center to wear faster and the tire would even grow a bit in circumference. Radial ply tires have more flexible sidewalls and a stiff belt under the tread. The tread does not deform as you increase the pressure within the specified limits and the tire's circumference does not change, or at least not much.

Increasing the tire pressure from the recommended 35/33 to 42/40 or 44/42 will make the car ride a bit stiffer. Traction on dry pavement will be slightly less but resistance to hydroplaning will be greater. The big plus is lower rolling resistance which does a lot for fuel mileage. The car should also track better and drive better because there will be less flex in the sidewalls.

 

<div class='quotetop'>QUOTE(tumbleweed @ Jul 27 2006, 02:11 PM) [snapback]293303[/snapback]</div>

My experience says otherwise and have seen it plenty of times with my customers. Ask any tire shop technician about it and they will concur that overinflating a tire will cause premature wear in the center of the tire. Even all the major tire companies post useful tips on their site and that is one of them.

This is also true with radial tires as well. You over inflate them and you decrese the "footprint" commonly referred to as the contact patch because the tire has a higher psi. Bias Ply tires were tougher as that is why they are recommended for trailers and such. Actually Bias ply are stiffer not softer and keeps the tire from "wondering" on the road. Have you ever been behind a truck towing a trailer and the trailer is swaying back and forth in its lane? That is because they are using radial tires and not Bias ply tires.

Yes at the cost of the tire wearing out alot faster than when set at normal pressure. We set them around 36 psi.

I am not going to harp on this because working in the tire repair and sales business as a certified Michelin and BF Goodrich representative and now for Toyota as an ASM I have seen enough to comment on this. It is up to the consumer to take it.

 

OK thanks for the discussion. I don't agree with some of what you say but I will keep an open mind and try to check it out.

 

<div class='quotetop'>QUOTE(tmorrowus @ Jul 26 2006, 02:47 PM) [snapback]292780[/snapback]</div>

All I'll say is that even if a tire is rated for a higher max psi than what you have it inflated for, I still think that 42/40 is a little excessive.

I'd drop it down to 40/38 or 38/36 and go from there. You'll notice an immediate improvement in ride and no noticably loss of MPG. I know, I started out high like you were and gradually let the air pressure down and found the the lower pressure, which is still higher than factory spec, works just fine.

 

We set the tires around 36 when they come in for service.

 

A little off topic but ... when looking at replacement tires, would the one with the highest mileage warranty be considered the hardest compound (and thus, have the lowest rolling resistance)?

 

<div class='quotetop'>QUOTE(McShemp @ Jul 27 2006, 07:24 PM) [snapback]293529[/snapback]</div>

Not necessarily, but some of the time yes. I think the hydroedges have the 2nd highest mileage warranty out there with a 90k warranty.

Also you can not compare the threadware rating(part ot the UTGQ scale) among different brands either. There test tires are different so you can only compare the same brands.