I wonder what is the best pressure in tires? I have a sign that 51 psi is maximum on my tires, and on the car itself I see 30 psi suggestion. What is the best pressure? The difference between 30 and 51 is pretty big. Now we have 40-41 psi in our tires. Any advice?

FoX,
40-41 sounds good, although there are others who have no qualms about going up to the max. I haven't heard of any of the max inflated people having blowouts, but I am still to chicken to do it myself.

Eric Powers

MHG Organizer - www.MadisonHybridGroup.com
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I've had mine at around 50ish for this summer which included a highway trip in a loaded car for 191 miles one way. Though my speed was low (around 50ish).

My hydroponics experiment

You ever notice how hard it is to lip read cartoon characters?
"Crazy is what the sane call Delta Flyer"

I've been at 49 PSI the last tank and a half and all has been well, but I'll admit the traction is an issue at times, be it extreme times. I spent 3-4 days a few weeks back in the rains and winds of Hurricane Ophelia when it was sitting stationary just offshore of me, and now the past 2 days have been all the nasty outskirts of Rita - when the road gets filled with water, I can feel a loosened grip and find myself taking extra precautions every second I'm driving.

My HCH tires have a sidewall rating of 44, and that is what I run them at.

I am just *very* careful in the rain.

-Charlie...

Listen to the tires not the manual, my tires say 44 psi max pressure, i just pumped mine to 42 (hot) dont max them out when they are cold and then go on a summer trip. The diff between a cold tire and a hot tire coulod be as much as 8-10 psi so i always check my pressures with the tires warm. So far i havent seen a big result in mpg over recomended pressures. Good luck. Dean

I have the Dunlop SP 20 FE (51 psi max). I've run them at 38, 40 and now 45. Since putting them to 45, my last 4 tanks have been 52, 48, 51 and 52 mpg. Lifetime average for the car (i.e. the 74 tanks before that) was 45.5. Now I raised the psi about the same time I got the computer upgrade, and refined some of my driving habits. However, I'd say that going from 38-40 to 45 likely made a 2-3 MPG difference. However, those tanks were all summer driving (70-80 degrees and dry). I have not driven in the rain or snow at that psi yet.

I need new tires in a couple months. Planning to get Continental ContiTouringContact CH95's which have a 44 psi max. I plan to run them at 40 psi.

Lastly, if I recall correctly 10 degrees of temp = 1 psi change up or down, so watch your psi as the seasons change.

*** Retired after 65,000 outstanding miles ***

I run 34 all around and get pretty good FE. I played with this and brought them up to 41 all around and noticed no difference in FE. The problem with running too much psi, is that you will wear out the tires in the middle more so then at the stated psi.

Hi All:

___I run a minimum of 50 #’s in all the vehicles except the MDX (Michelin X-Terrains have a max sidewall of only 35 #’s) so she sees 40 when I drive on vacations and 35 as my wife’s daily driver. I have been running 52 #’s in the Michelin MXV4’s on the Accord over the last month and fill ~ every 6 weeks as they bleed down to just below 50. 50 #’s in the Ranger’s Contitrac’s and Corolla’s Integrity’s … The last 3 automobiles max sidewall are all 44 #’s.

___Good Luck

___Wayne R. Gerdes
___Waynegerdes@earthlink.net

Probably worth a mention that burst pressure is much higher than rated PSI, so no worries if you go over a pound or two.

Safety issues with high PSI are primarily handling, and to a lesser exent treadwear, although if you rotate it usually isn't an issue even with running at sidewall maximum, especially with front wheel drive cars like ours.

I run my tires at the sidewall maximum of 44, haven't seen any rain yet, but rainy season is starting here. If it is the least bit squirly I will try dropping to 38ish which is what I ran all my previous cars at and never had any problems in rain (and we get lots out here in northern CA). High PSI helps prevent hydroplaning, but hurts traction in wet, so it is a tradoff no matter what you do.

These LRR tires we have should be pretty sticky, as softer compounds are usually needed to produce LRR. Traction A anyway.