Tire pressure on Bridgestone Ecopia EP422??

on my Leaf I have them at 42 PSI. i find that the ride harshness difference is difficult to quantify on most of the roads i seem to drive on, so that is not an issue for me. i also find that inflating them to near the max (44 PSI) seems to give me more even wear across the tread and more miles. on the 2006 with the OEMs it was 42/40 with tire rotations every 5,000 miles done myself and they were replaced at 53,000 miles (rated to 50,000) when most were replacing them at 30-40,000

 

Run them at either max (what it says on the side of the tire) or no less than -10% of that #. IE: max44 psi run at no less than 39.6psi. The tire companies spend millions on research and testing for each tire to insure even wear and durability. Always go by the tire manufacturer's recommendations and not necessarily the Nader sticker inside the door of the car. Toyota makes cars, not tire's. At max PSI you will have a bit of a rougher ride but get better mileage. At the lower PSI you will have a better ride but decreased mileage but if you keep it within the PSI range I stated above you will very likely not notice much of difference either way.

 

I recently had Costco put these on, ecopia 422. I went on a trip and mpg was down. I stopped in at another costco after I found my tires set to 30-32 all around, unevenly. The guy said we are told to set at the 35/33, but what do I want. I said 37/35, which has been my pressure for the five years of ownership. My Integritys were at 40k, at least 10k left before bars hit, but I got a side puncture so got a new set on the sale. It's a bit harder ride, but a good compromise I think. For me, any more than 37 cold is way too hard a ride. MPG seems to be back to about like the Integritys now. I don't subscribe to the sidewall rating which is a maximum rating for the tire. Harder tires put more stress on suspension parts. The car label is the one to go by and work up from there according to feel and how you think mpg is. I tried higher once saw no increase I could measure, in my use of the car which is a lot around town, and hated the car's ride. Pressure varies with temperature so it isn't all so exact.

 

Different tires (even the same exact size) by different manufacturers have varying PSI ratings because they use different compounds, radial materials and sidewall thicknesses. The goodyear integrity's I believe were 40 max PSI tires, therefore 36 to 37 would have been appropriate. the Integritys are much softer tire having only a 50k warranty, the Ecopias are a different compound (harder)
with a 65k warranty. Remember a few years ago when all the SUV's were flipping over? That was all because of insufficient tire pressure. Many tire shops put a standard 35 psi in every tire! They even did this to my truck tires which are designed to be run at a whopping 60psi!
I don't think you really need worry about your suspension...we have 160k plus on our Prius and the struts are still in excellent shape all the while running my 44psi rated tires at 42psi.

 

I have the EP422 for 2 months now. I run 40 on the front and 38 on the rear. I am comfortable with these pressures. I haven't noticed any mpg loss with the new tires. I hear that some do get an mpg loss with new tires. Thanks Mike Mc for your info- 160k is great. Now I won't lose any sleep worrying about suspension wear.

 

I decided to go back to 35/33 because I couldn't stand the brittle harsh ride. Ride is so much smoother and mpg's haven't suffered.

 

FYI, Costco has Bridgestones on sale - $100 off. Just spent $369 installed including tax for a set of four EP422's.