The new July 2010 Consumer Reports has a few pages titled, Gas-Savings Tires. The tires are rated for dry & wet braking, handling, hydroplaning, snow traction, ice braking, ride comfort, noise, rolling resistance and tread life.

CR rates each of the above as excellent, very good, good, fair and poor.

I'm using the michelin saver a/s tires. I only have about 7000 miles on this set. When I try, I can get 6 to 7 mpg (no AC) better mpg over the original energy tires that came with the car. With near normal driving with the AC, I get around 3 mpg better. These results were from testing last last summer and recently, may 2010. The temperatures in southern new mexico have been around 90 to 95 degrees with humidity down to 9% most days.

I have nitrogen in the tires, at 44 psi cold pressure. I doubt the nitrogen helps the mpg any although their are some advantages. I have found the 44 psi nitrogen rides about the same as 41 psi when using air in these same saver tires.

It's now a night later and was 101 degrees today. The tires not driven and sitting in the shade read 44.5. Tonight at midnight the temp was down to 80 deg. I decided to let them down to 42 psi cold. Now when driving in 101 to 104 degree temperatures they should not grow over 45 psi.

I did a tread depth test at 42 psi if that matters. The center read only a fraction under 9/32 and the side treads at 8.9/32. When new, the center was 9/32 and sides at 8.95/32. This saver a/s tire looks to be a long wearing tire. I'm using the Longacre micro dial type gauge I bought from Amazon.

 

Thanks to all who replied. When I went to Sam's the first time to order tires I told them what car I had and they only wanted to sell me the same speed-rated tire. I went back and simply ordered the tires I wanted in the correct size. They were not in stock but arrived in a few days and they installed them with no problems. I got the Michelin Energy AS with discounts that almost paid for one tire. So far I am very happy. The reviews I saw for the tire are very good. They may be a touch noisier at 65 mph and above.

Due to concern about the lowered speed rating (from V to T) I checked various websites: Michelin, Goodyear and Edmunds. They all indicated that downgrading the speed rating would not be a problem so long as the tire speed rating is not exceeded. I also learned from a Michelin publication in the store that actually obtaining the tire's published speed rating requires increasing the tire pressure by three pounds. In other words, the standard air pressure results in a speed rating less than the maximum rating for the tire (according to Michelin). A good tip to know!