Nokian WR 5K review

Richard has it right. My 2004 Prius now has 104k miles. The Integrity tires were poor in all aspects (even inflated to 42/40 psi) and I took them off at 44.5k miles. The Michelin MXV4+ "Energy Saving" tires (H-rated) I put on next were much better:

1. Great handling
2. good traction dry/wet, but only a little better in snow/ice
3. About 0.5 MPG improvement over the Goodyear's.

But are no longer available in our size (185/65R15).

I took them off a little early (55k miles of wear, they could have safely gone 60k miles) as winter was approaching and put on the Nokian WRs (H-rated, they are also available as T-rated for $5-$7 less per tire - get the H - stronger tires). My results to date are similar to yours (also at 5k miles) so I am very pleased with them (my son-in-law just put a set on his 2005 Prius as well).

It is early to quote accurate data, but the WR's appear to be getting better MPG than the Michelin's (both also inflated to 42/40 psi). So they are indeed LRR tires.

JeffD

 

I'm intruiged by the MPG gain. Are you guys being very careful to account for any climatic, road surface, and driving technique changes that may have influenced the mpg difference?

I know the Nokian NRT2 were rated pretty well for LRR according to Green Seal's .pdf but since the Integritys were not listed I couldn't compare. The Bridgestone B381s had a very low RR rating but I didn't see them in our size.

 

If you read my spreadsheet carefully, you will see a side analysis that compares the Integrity's to the Michelin's over a full year of use (each tire's last year - November through October). My driving habits are reasonably consistent year to year and I took into account each tire's revs/mile when new and adjusted for their tread wear (increases revs/mile in a predictable way, I am an engineering professor ). Averaging over a full year does tend to average out the uncontrollable variables so the 0.5 MPG improvement is real.

The use of organo-silicates (and vegetable oil in the WR's?) in the rubber compound seems to indeed reduce rolling resistance (especially in cold weather) .

JeffD

ps:
1: This November was actually colder than last November (I track degree days in CT) and I took one of my regular trips to Chicago during a winter storm this month (December) which drove my MPG down so it does indeed look like the WR's are going to perform well in saving fuel.

2: You can get relative LRR readings directly from Nokian technical support (at least between their tires). For example they told me that the WRg2's have the same rolling resistance as the WR's in response to an email query.

 

Sorry i didn't read the spreadsheet Jeff, I clicked on it and my WinZip program popped up and I was reluctant to add the file to my computer. *looks embarassed*

Thank you for the detailed info.

 

Would it be worth asking Michelin (email) why this size has been dropped as it would find a market among Prius owners as it has shown to be a better tyre than the OEM tyre? This may influence them to restock them.
Or are they available in 195 / 60R15? which has the same rolling radius near as sh** is to swearing anyway.
Although I think the 185s would perform better in snow and ice than 195s, yes? no?