New tires YOKOHAMA AVID ASCEND . Loss about 1-2 mpg. Not upset.

Did you get regular YOKOHAMA AVID ASCEND or newer YOKOHAMA AVID ASCEND GT? Both are similary priced and have similar specs. The older ASCEND maybe going to be discontinued soon? I had ASCEND on my older cars, and liked it, but thinking of trying ASCEND GT.

 

I got the GT version and I love them. They did great in heavy rain. Not sure about fuel economy since I got them just as the summer heat hit.

 

I went from the Pirelli Cinturato P7 A/S to the Avid Ascend GT at the beginning of April (April 8th to be exact). The initial hit with the new tires was a loss of 2-4 mpg for the first 1,000 miles or so but by 3,000 miles the tires were already delivering about the same gas mileage as the older tires. I expect them to get even a bit better as the tread wears down over time. The last five tanks have been calculated as 44.11, 42.33, 43.86, 43.3 and 45.12 mpg, right in line with or a hair better than the car's 42.89 lifetime average. I'll know a lot more about them when we return from driving to the East Coast and back in July..

 

As the pressures go up, center tread wear also goes up and you beat up your suspension components a lot more. The savings in fuel at these pressures may be more than offset by these costs.

 

Even radials will narrow the tread pattern at high pressure.

"Excessive air pressure will cause the tread face to bulge, reducing the contact patch."

 

I think several not so good things can happen at extreme pressure:

1. Increased suspension/bearing wear. (mentioned by @jb in NE)
2. Punishing ride. (more so with the low-profile 17's)
3. Maybe more tendency got lose lose grip over little bumps, especially when cornering?

 

I'm not sure there's anything to be gained by pumping them over 38-40 psi. If there's any increase in mpg, it'll be well within the range of other influences like weather and traffic, so not enough to be a clear measurement. And the Prime already gets such incredible mileage that I don't fuss about a couple psi and would not want to run my tires close to max psi.

Another thing I've noticed is that at high pressures the steering gets kind of touchy since the car's weight isn't as even distributed across the tread. It may not wear faster in the middle, but radials don't completely eliminate the tires' tendency to get rounder at higher pressure.

 

I hope you get lots of miles. Very few get close to the rated mileage claims.

Making a mileage warranty claim is next to IMPOSSIBLE and oftentimes worthless b/c of the fine print. The biggest impediment against owners, in making a mileage warranty claim, is the requriement of even wear across the tire tread.

Why Tread-Life Warranties are Next to Useless - Consumer Reports​

That's some punishing PSI! You have a pretty high pain threshold?

 

Why? No change in mpg... or you bottom hurts?

 

Boosting it high doesn't make a lot of sense in my driving conditions. I spend my summers running through the Mojave Desert at 65-75 mph. There may be a 40 or 50 degree difference in the morning between the air temperature in my garage and the highways I'm driving. Driving those conditions adds a minimum 4 or 5 psi. I just try to set them at 38 psi front, 36 psi rear and enjoy the drive without rattling my teeth or facing a blowout. Destroying the suspension, tires or my family is not worth a few mpg.

 

I have the same tires. Still love them. Had a temporary small reduction in miles/kWh. They are wearing great and still give superb wet weather traction after about 25k miles.