Just came back from a trip to Vegas with Continental ExtremeContact DWS 235/45-15 installed on the E430 a month ago.
I tried 42 PSI before the trip for a month, I felt that the sidewall is a little soft so that I inflated to 48 PSI with the max of 51 PSI on sidewall. It was a mistake to have that high pressure at 70F ambient temp. The temperature at Death Valley was 115F and 110F at Vegas, with about 40F more the tire pressure was above max pressure of 51, the car was not very stable with strong cross wind when I was around Death Valley, the ride was pretty hash aver the bumpy road, but the gas mileage was very good at around 24-25 MPG.
While we were at Vegas, I borrowed the tire pressure gauge and adjust all tires down to 45 PSI. The car was much more stable on the way back to California, even the cross wind was stronger. The gas mileage suffered about 0.5-1.0 MPG. The tire noise was very low with either pressure.
I am very satisfy with DWS, its performance is as good as Falken FK452, the ride is better at 45 PSI and the noise is lower. The FK452 lasted only 20k miles, it's too soon to know the tread life of DWS, but is is rated at 540 so that it should lasted more than 30-35k miles.
I tried 42 PSI before the trip for a month, I felt that the sidewall is a little soft so that I inflated to 48 PSI with the max of 51 PSI on sidewall. It was a mistake to have that high pressure at 70F ambient temp. The temperature at Death Valley was 115F and 110F at Vegas, with about 40F more the tire pressure was above max pressure of 51, the car was not very stable with strong cross wind when I was around Death Valley, the ride was pretty hash aver the bumpy road, but the gas mileage was very good at around 24-25 MPG.
While we were at Vegas, I borrowed the tire pressure gauge and adjust all tires down to 45 PSI. The car was much more stable on the way back to California, even the cross wind was stronger. The gas mileage suffered about 0.5-1.0 MPG. The tire noise was very low with either pressure.
I am very satisfy with DWS, its performance is as good as Falken FK452, the ride is better at 45 PSI and the noise is lower. The FK452 lasted only 20k miles, it's too soon to know the tread life of DWS, but is is rated at 540 so that it should lasted more than 30-35k miles.