Tires: Low rolling resistance vs longer life?

I faced the same dilemma. I chose the X-Radials for the reasons you stated, plus the fact that they are better rated for safety in almost every area.

Most reviews I see of the MXV4+s say around 40K for the tread life, and since the X-Radials are less expensive to start and last longer, I figure from a cost (to me) standpoint there's no way the slight mileage increase for the MXV4+s would outweigh the higher initial cost plus the earlier replacement cost of the tires.

CR rated the X-Radials excellent on rolling resistance in their previous review, and though I suspect the MXV4+s are in fact better, I don't think the Xs are terrible.

That being said, I do have a noticeable mileage decrease with the Xs, but I've only had them on a short time, and I put them on at about the time of the shift to Winter Fuel, so sorting out just how much is the tires, and how much they may improve as they break in will take some time.

And, as you said, from an environmental standpoint, putting 4 extra tires in the trash has to outweigh the few gallons of gas they may save over their life.

So, I fell down on the side of the Xs. YMMV.

 

I'm putting a set of MXV4+s on our 2006. I'll let you know what I think after I drive with them for a while.

Tom

 

<div class='quotetop'>QUOTE(prberg @ Oct 19 2006, 03:18 PM) [snapback]335203[/snapback]</div>

Used tire disposal is an environmental problem, and tires take resources and energy to manufacture. I can't imagine that buying tires that last half as long but save say 4% on gas mileage (about 2 mpg in Prius which is what I have been told) is a good environmental or economic decision.

Doing a bit of math, assuming 48 mpg with "regular" tires and 50 mpg with low rolling resistance tires, gas at $2.50 per gallon, tires at $120 each (mounted and balanced), and 40k vs. 80k mile tire life yeilds this:

Drive 80,000 miles with "regular" tires
Gas cost: (80,000/48) * 2.50 = $4167
Tire cost: 4 * 120 = $ 480
Total = $4647

Drive 80,000 miles with LRR tires
Gas cost: (80,000/50) * 2.50 = $4000
Tire cost: 8 * 120 = $ 960
Total = $4960

Savings using "regular" tires: $313

Based on this, I just replaced my original Goodyear Integrity tires (worn out with 37,000 miles on them), with Michelin Hydroedge (80,000 mile warranty). It is too early to give a report on mileage, but the Michelins are quieter, have a better ride and handling feel, and much better traction (we had a blizzrd here in Denver Tuesday!).

 

I used to run Xs on my Honda CRX. I never got anywhere near 80,000 miles with them. The tread would still be good, but the sidewalls cracked long before that from sun and age. Maybe if I had driven more miles per year the sidewalls and tread would have worn out together.

Tom

 

<div class='quotetop'>QUOTE(kingofgix @ Oct 19 2006, 04:51 PM) [snapback]335244[/snapback]</div>

Having had a set of MXV4+'s on my previous car, I'm planning on a set on my Prius when the Integrities wear down some more. I just can't quite bring myself to buy new tires when these are still servicable. Once poor, never rich. A few questions for you: Are the Hydroedge's and the MXV4's the same price? Is there really only a 2MPG difference? It does rain here a bit, and most of my refresher courses on the laws of physics have involved hydroplaning or not stopping in time in rainy weather.

I can't fault your math, but my experience with tire warranties is usually something like this: The tires wear out at 80% of their life, so they'll give you 20% off on a new set. But the car has by that point something like 100K on it, and I don't want to spring for another set of top of the lines for a car I'm only going to keep another year or two.

 

<div class='quotetop'>QUOTE(prberg @ Oct 19 2006, 11:15 PM) [snapback]335385[/snapback]</div>

They had 45K on them when I traded the car in, not quite down to the wear bars, but getting close.

<div class='quotetop'>QUOTE(prberg @ Oct 19 2006, 11:15 PM) [snapback]335385[/snapback]</div>

For some reason, I was thinking those hydroedges were much more expensive. Thanks!

 

<div class='quotetop'>QUOTE(kingofgix @ Oct 19 2006, 04:51 PM) [snapback]335244[/snapback]</div>

I also replaced the original Integrity tires with the Michelin Hydroedge. It rains alot here in Oregon and I figured the added traction would be a bonus. They are very quiet and a good ride, but I seem to have lost about 3 mpg out of the deal. I have about 2500 miles on them now and would highly recommend them to others.

 

<div class='quotetop'>QUOTE(Beryl Octet @ Oct 19 2006, 10:50 PM) [snapback]335376[/snapback]</div>

They were about the same price at discount tire. John1701a at John1701a.com put Hydroedges on his Prius some time back and reported a 1.5 mpg drop, so I used 2 mpg to be conservative.

As far a tire life, I'm can only tell you this. My brother had Michelin tires (don't know which specific model) last for 100,000 miles on a Toyota Camry. And I had a set of Michelin Hydroedge tires on a volvo that got totalled when the tires had 60k on them. I believe they would have made it to 80k or beyond. I do not know how long the MXV4's will last.

 

<div class='quotetop'>QUOTE(kingofgix @ Oct 20 2006, 10:09 AM) [snapback]335509[/snapback]</div>

Thanks. I'm going to have to look into a set of those then.

 

as i understand it, LRR v longer life is an oxymoron. less rolling resistance means less wear meaning longer life. any decrease in tire life would be more contributable to lesser quality or design life more than anything else.

i suppose the smaller footprint of an LRR would cause the existing tread to have a higher contact time, more rotations per mile, etc. but if everything is equal, i would have to say the LRR would always last longer.

i think the issue here is getting a better quality LRR tire.

 

<div class='quotetop'>QUOTE(kingofgix @ Oct 20 2006, 10:09 AM) [snapback]335509[/snapback]</div>

I have the MXV4+ (185/65R15) on my 2004 Prius. After 25,000 miles (the OEM Integrity tires went 45,000 for me), they are wearing reasonably an should hold up for 50 to 60 thousand miles. I run my tires at 42/40 PSI which does make for longer tire life (as well as better MPG).

JeffD

 

<div class='quotetop'>QUOTE(DaveinOlyWA @ Oct 20 2006, 10:19 AM) [snapback]335520[/snapback]</div>

I'm sorry but your understanding is somewhat flawed. LRR tires generally achieve lower rolling resistance by reducing the energy lost when they flex. They are not inherently stiffer tires. The reduced energy loss is achieved by replacing some of the carbon black with organo-silicates in the rubber compound. This also tends to improve wet and snow traction so premium snow tires also use similar rubber compounds.

Since organo-silicates cost more than carbon black, LRR tires tend to be more costly and due to the stickier rubber compound the tread wears somewhat faster.

I have documented a measurable MPG improvement in MPG (especially in cold weather) using the MXV4+ tires versus the OEM Goodyear Integrity tires on my 2004 Prius (see attachment)

JeffD[attachmentid=5398]

 

I'm in LA area. Based on My 2004 users manual I think I would like to buy these instead of M+S. I haven't found any dealer who sells summer, only M+S.

Any summer recommendations?

I subscribed to Consumer Reports and will prob buy one of top rated H tires if I can't find summer.

Any suggestions?

Thanks

doug

 

Don't have them yet... but looking forward to my ordered 2007 Touring with Bridgestone Turanza P195/55R16 86V tires on the 16" wheels. They claim LRR - 70K mile limited treadwear warranty - 3 yr Platinum warranty.

Sounds like a giant step *UP* from the Integrities provided on my 2004 Prius. The tires alone are worth the ~$142 more I'm paying for the Touring version vs. the standard Prius.

*SIGH* I need to exercise my patience during the wait. :mellow:

 

<div class='quotetop'>QUOTE(dahprius @ Oct 24 2006, 03:26 PM) [snapback]337520[/snapback]</div>

Good idea. I loved buying summer tires when I lived in Phoenix. When you have no need for snow or ice traction, using a summer tire dedicated to dry and wet traction performs much better.

The Sumitomo HTR 200 is a low rolling resistance tire according to Green Seal and the Transportation Research Board. According to user surveys at tirerack.com, its a great high performance summer tire. It's also competitively priced. They don't make it in an OEM size 185/65r15, but they do make it in sizes 195/60HR15, 195/65HR15, and 205/60HR15, which will work on your Prius.