Prius Fast Tirewear - Important Update

Higher psi tends to reduce rolling resistance and thus increase gliding ability and MPG. It also stiffens up the sidewall which allows me to corner a bit harder. Higher pressures also (within reason) reduce tire deformation which reduces heat buildup so you are less likely to experience tire failure.

Many people run very high pressures in their stock Integritys with great results and no abnormal wear. I've read of pressures up to 70psi and one bloke who runs 100+psi. We've had a lot of discussion on this subject and with the number of people running these high pressures and the fact that burst pressures are so high I feel safe enough to continue doing it. I never recommend it to anyone however. In the end I am pushing the pressure higher and higher till it seems I've reached a point of diminishing returns. I htink I'm near that point and I do not intend to go any higher. I may drop it back down a bit.

Here is a poll on tire pressure on CleanMPG.com

Awesome information contained in the article below.

Tires and Passanger Vehicle Fuel Economy (.pdf) data below is from pages 63-68 or so.​

"Only about 12 to 20 percent of the energy originating in the fuel tank is ultimately transmitted through the vehicle’s driveline as mechanical energy to turn the wheels. Rolling resistance consumes about one-third of this mechanical energy output. Rolling resistance, therefore, directly consumes a small portion (4 to 7 percent) of the total energy expended by the vehicle. However, reducing rolling resistance, and thus reducing mechanical energy demand, by a given amount will translate into a larger reduction in total fuel consumption because less fuel energy will need to be sent to the engine in the first place. The effect on total fuel consumption will depend on a number of factors, including the efficiency of the engine and driveline as well as the amount of energy used by accessories. As explained later in this chapter, for most passenger vehicles, a 10 percent reduction in rolling resistance will lead to a 1 to 2 percent increase in fuel economy and a proportional reduction in fuel consumption.
​

Tire Operating Variables and Hysteresis (pg 68)

Inflation pressure affects tire deformation. Tires with reduced inflation exhibit more sidewall bending and tread shearing. The relationship between rolling resistance and pressure is not linear, but it is consistent enough for rules of thumb to be applied. Schuring (1980) observes that
for conventional passenger tires, an increase in inflation pressure from 24 to 29 pounds per square inch (psi) will reduce rolling resistance by 10 percent. For a tire inflated to pressures between 24 and 36 psi, each drop of 1 psi leads to a 1.4 percent increase in its rolling resistance. The
response is even greater for pressure changes below 24 psi. Maintenance of tire pressure is therefore important in preventing excessive deformation and hysteresis, as well as in achieving intended wear, traction, handling,
and structural performance.The temperature of a tire is affected by ambient conditions, tire design and materials, running time, and speed. Higher ambient temperatures are
associated with reduced rolling resistance because the amount of energy dissipated when the rubber is subjected to repeated deformation declines moderately as temperature rises, which is a commonly observed behavior
of viscoelastic materials. Accordingly, the length of time a tire has been running since the last cool-off affects rolling resistance, which declines until the passenger tire has been rolling for about 30 minutes."​

Tire Design and Hysteresis (pg 67)

On a side note, I found this information regarding rolling resistance changes over the lifespan of a particular tire. ​

"Related to the effect of tread mass and volume on hysteresis is the effect of tread wear on rolling resistance. As tread depth (that is, the depth of grooves in the tread pattern) diminishes with wear, a tire loses about 15 percent of its mass—since the tread band typically accounts for about onequarter of a tire’s weight. The moderating effect of tread wear on rolling resistance has been examined and quantified to some extent. Martini (1983) compared the tire rolling resistance occurring when the tread was new (100 percent) with that occurring when the tire was buffed to various stages of wear (75, 50, 25, and 0 percent remaining tread). These experiments suggested that rolling resistance declined by 26 percent over the entire wear life. After reviewing many similar experimental studies conducted before 1980,
Schuring (1980, 683–684) concluded that rolling resistance declined by an average of about 20 percent over the tread life, dependent on design details.​

 

Larry, are you still getting the kind of milage that was listed at the time of your post here? I think it said your overall average was about 70. What are you doing to get that kind of milage? BTW, I have about 26,000 on my 07 and the "lack of" Integrity tires are about worn out.

Thanks

 

I doubt the OE tires on a Prius are any worse than most cars in this price range. At least they install all-seasons. Some cars have summer OE tires which are useless in the winter. The Integrity is a cheap OE tire used in a lot of new cars. It is a medium-wearing tire. 25-30K miles is the normal life of such tires.

 

My average since I bought the car 5-19-08 is 72.3 mpg. My current tank is running 86-87 mpg after 672.9 miles with 4 pips showing on the guess gauge. My signature has my latest stats.

To get this mileage I do as much pulse and glide as I possibly can. Again, I drive on county/rural roads whenever possible to stay away from traffic so I can keep my speeds at no more than 40 mph. I try to plan my trips ahead of time and to combine trips and to make sure that I'm not rushed for time.

Contrary to what has been alluded to in a couple of other threads, I don't drive this way to just brag or show off to others. It's about saving money, producing less pollution, exploiting the car's capabilities to their fullest, and constantly trying to improve myself every time I get behind the wheel; and not necessarily in that order. As I've mentioned before, I'd be happy to answer any PM's anyone wants to send or arrange to meet in person or talk on the phone to try and answer questions about how I do what I do.

My original Integrity's are looking great after 19K miles and have been at 70+psi since last October.

 

In my experience, OEM tires have always worn out early. Auto Manufacturer's as a whole, do not put good tires on new cars. Its just a fact. I tried the premise of this thread with my dealer and they balked all the way. So did Toyota. I currently have about 23K on the Goodyears and based upon the wear pattern, I would expect to get just over 25k on them before they have to be replaced. This to me, is typical of my experience with OEM tires. I have read all the threads on replacement tires, done my research on Tire Track, and talked to my Toyota Dealership. They are recommending Yokohama tires of the same size as comes on my 05 Prius.

I am strongly leaning towards the Michelin Primacy MXV4. I feel even going to the 195 size has a potential to reduce my mileage. If I can improve ride, traction and wet pavement grip, my goal will be attained.

 

so what is a good alternative tire for the Turanzas from a touring?

 

IMO, Nokian WRG2 if you need to drive in Winter and don't need ultimate winter performance, but do need snowflake certified and also want to run same tires in summer. That's my plan...

 

I stopped at a station 2 blocks from the dealership last September when we picked-up my wife's 08 Touring and put 50psi in the Turanzas. We just complete about 1800 miles rt to VA and back with it cram packed loaded with 60 psi in them. 13,000 miles and still look good.

 

With 70 lbs plus, isn't the tire tread wear considerably more in the center, compared to the edges

 

i get fast wear on the front right tire and cupping on the inner rear right tire. i read a thread where someone mentioned that several prius owners stated a need for shimming the rear tires... assuming the right side... something about being tied down while shipping.

I was waved to at a light the other day where an older gentleman mentioned he is having a tire wear problem and was riding on his spare after only 30k miles.

My last set of tires 215/45/12's only lasted 20k miles or so...

 

thanx, but being in california, is there more of a "summer" tire i could use, that allows higher grip???

 

Nope. Guess I'll have to take pics of mine so people will put that idea to rest.

 

08 here, Rural mail carrier 50% of the miles, 40% average 2 lane, 10% expressway, 12,000 miles and the tires look worn. The dealer has done all the oil changes (for free) and we have had the tires rotated at ea. oil change (we paid for that part). 1/2 of the posts seem to say 20-25K is normal.

So here is the question,
Is there an argument to be made to the dealer, (before the warranty runs out), for new tires, or at least a full alignment @ N/C?

 

In case Tim(brick) doesn't get a chance to post his pics here, take a look at these pics of his Integrity's at 27K miles.
Tire pics: GY Integritys @27k mi, 44psi - CleanMPG Forums

 

Here are my Integritys with over 35k and 50psi+

http://priuschat.com/forums/care-ma...24-integritys-over-35k-miles-50-psi-pics.html

 

I have 30,000 miles on the original tires and there is still plenty of tread on them...I will replace them with the same tire. I suspect the people that get less are normally hard on any tire.

 

KANDYREDKOI - hey my fellow asian brother......................i opted with the BRIDGESTONE POTENZA'S G019'S. they are handling awesome! i live in sunny so-cal and so far, minimal mileage hit....................i went from 47.7 with the stock INTEGRITY'S, to 47.0 with the potenza's. MAJOR traction addition too. Yes, i tried a set of turanza's, not mine, a buddy's. I pumped them up to the maximum psi that the tire stated, which is 44 psi. yeah, i'm a chicken, but oh well, such is life. Such a difference when i used to run 20 psi's in my CHEATER SLICKS!

 

Gee My brand new 2008 has the 2006 navigation software in it? whats with that so much for being upto date. Toyota can build a Great Car but can't install updated software.

 

I saw a set of Integitys on a year old Ford commercial van that looked about half worn with 70K miles on them. The driver thought they were great OE tires.