42/40 = uneven tire wear or unsafe?

I ran 40/38 on my '02 for 54K mi. and the wear was perfectly even. Those were Bridgestone Potenzas, too, not a very good tire otherwise.

And yes, technically safety could be a slight factor---mostly, I think, in the event of having a slight bounce if you drove over something, thus temporarily losing grip with that wheel, instead of "squishing" over it.

 

nope... on LRR tires, pressure has to be much much higher before crowning becomes a problem

 

It's a non-issue.

Pressure all the way up to the maximum is what a good quality tire will maintain its shape at nowadays. After 30,000 miles with my HydroEdge tires running at 44/42, the wear is still even all the way across the surface.

The days of rounding tires are just bad memories from decades past.

 

I'll second Evan's response - I kept my stock Integritys at 42/40 for 50k and they still wore out on the edges first. Started to become evident at 25k or so. I was scared to go higher, but wondered if I could even out the wear.

 

edge wear is normal under all conditions if the tires are not properly rotated and balanced. front tires will wear on the edge faster and this wear is FASTER for underinflated tires. normal for ANY other pressure. that is why front to rear rotation is critical. a rebalance is recomended for each 25-33% of usable tread wear loss.

edge wear occurs while turning and can not be avoided. for most tires, a small amount of overinflation will slow the wear down. the rears because they are pulled around the corner with minimal weight on them, dont distort and dont wear on any spot unevenly

 

Edge wear on front is now more related to hard/fast cornering than to pressures within the tires rated ranges. That is, if you don't have a alignment problem.

 

I got 40k miles at 38-36 to 42-40 psi ranges.

Tread_Depth_(mils)____Integrity_after_40,080_rotated_every_10k
_________FrontLeft__________FrontRight__________RearLeft_____________RearRight
Inside_____14___________________15_______________17__________________13
Middle____12___________________15_______________16__________________13
Outside____10___________________11_______________12__________________12

 

LRR tires? What's that Dave?

 

Low rolling resistance.

tires specially designed to keep their figures in a manner of speaking. iow, they stay round. this reduces the flexing of the rubber as the tire spins, (the flat side is not very flat) which reduces heat caused by friction and increases tread life and decreases comfort.

at work we share our parking lot with the WA state dept of Health. few years ago, WA State mandated that all state funded fleet vehicles (if they wanted their funding to continue) had to upgrade to alternative fuel vehicles that reduced polution (if such a vehicle existed). The Prius is still the best choice going. so there are a BUNCH of Prius state vehicles there.

i have had several opportunities to talk with employees there and their reactions to ride comfort ranges from

"rides fine. no complaints"

to

"i would never spend my money on it"

i talked to this one lady who, by far, had the strongest opinion on it (i think she has control issues...seemed very nice though) who said that if riding in the back seat, in less than 10 minutes, she had a pounding headache. she surmised it was either the vibration or some subsonic frequency that did it (she claimed to be sensitive to that). but she also said she liked the vehicle and didnt have any issues if she was driving...

i have never riden in the back of my Prius so i cant say, but i have had a lot of passengers and all are totally impressed with the leg room of the back. only average comments about comfort. i do know that more than a few were jealous that the front seats reclined back to nearly any position.

now with the DOH people, i also noticed a very very obvious general disdain for fleet cars in general. there is only 2 non Prius cars i have ever seen over there besides vans and they are very large 4 door sedans. boat types, i call em. dont know if they just want to drive a car that gets 12 mpg without having to pay for the gas or they just want to drive them because they seem much more exclusive.

 

I run my tires at 37/35. Based on posts on PriusChat I tried 42/40 for several weeks and then reduced them to 38/35. I thought that both the ride and handling were improved and I saw no change in gas mileage.

 

I have settled on 36/34. Higher pressures may give better mpgs, but the ride is harsher and I feel that this contributes to rattles appearing before they should.