I got rid of the original Bridgestones at 55k miles. They actually had a little life left in them at the time. The only reason that I replaced them was that I hit a curb and blew out the side wall on one of the tires. I replaced them with the Primacy MXV4's. To be perfectly honest, I can't tell the difference between the two tires after 15k miles. I don't think they're any more quiet or handle any better than the original tires.

 

Just replaced my junky Bridgestones (lasted 28K miles) with Michelin Primacy MXV4s. I have only driven 5 miles home on them, but have already noticed they are much quieter than the Bridgestones.

FYI, when researching this, I noticed that the P215/60R16 size (and only this specific size) in the Primacy is a Green X tire, which my understanding means it is LRR and reduced CO2 emissions (whatever they mean by that). Sure enough, I see a Green X symbol on the tire itself.

 

I decided to replace my oem Michelin Energy S8 tires. A few days ago I bought a set of tires from the TireRack.com/ people. I choose the new Michelin Energy Saver a/s tires. These also have the green x designation. I understand the green designation is a new rubber compound that improves the gas mileage.

My gas mileage this last year has been rather stable. I'm looking forward to seeing any increase in mpg over the oem tires that I have been using.

 

rburt07, yeah I looked at those too. Compared to the Primacy, slightly more bucks, slightly less tread life (and no warranty), and also Green X, so I went with the Primacy. But I would think they are very close in performance, and almost the same choice.

I had my first commute on the Primacys today. The car handles quite different, especially in corners. With the Bridgestones, there was a pronounced under-steer, and with the Michelins the handling is more neutral.

 

I don't think a Green X automatically mean the tire is extreme LRR. Reading up, it does seem to be Michelin's symbol to identify their lower rolling resistance tires, but still, without specific rolling resistance numbers, I would take it with healthy scepticism. Almost seems like a license to print money: Sales down? Put the Green X on a few more tires...

 

The michelin green-x is a improved rubber compound that improves the LRR tires. The energy saver tire includes a radial design that helps improve the gas mileage.

I also noticed no tread life warranty on the energy saver tires. I have had many sets of michelin tires with no problems. I did have a older set of michelin-x tires on my wife's car. They had small heat cracks on the backsides. Discount tire gave her a brand new set for about $80 to compensate for tread depth usage.