so on my dodge it has some kind of economy tire and says max tire pressure is 51 psi and the sticker on the door says 30 psi. anyone have any ideas on what pressure i should run?
Funny, I just talked to my mechanic about this 5 days ago. He said most tire places inflate the tires to vehicle recommendations, not the tire. Especially since tires have gotten much better than they were in the past, he likes to go about 10% less than max tire pressure on the front, and maybe 12-14% less on the rear. I have Michelin tires on my wagon with a max PSI of 50. He said he likes to go at about 44/45 on the front, and maybe 42/42 on the back.
This question was smack dab in the center of the Explorer tire debacle, and from the things I read from the SAE and the ASE on the subject, here are what I do: 1) any vehicle with RABS or without any ABS system gets a higher pressure up front, 10% of max pressure, than the rears, 15%, unless the vehicle carries or tows a load, then max all around. Even a 3/4 or 1 ton with work tires weighing in at 80 PSI gets that treatment; 2) vehicles with 4WABS gets 10% all the way around unless fully loaded (my Exploder carries a few hundred pounds of tools and materials, so it gets 35PSI on its highway tires); 3) always remember, the car company will want a more compliant ride to please the owner/driver, but the driver MUST remember the tires require full inflation before carrying any load; 4) the only exception to these are cars with LRR (low rolling resistance) tires, which must always be inflated to full pressure. Any danger of a catastrophic blowout is outweighed by the car's extreme light weight.
The answer is subject to change if you wait a little while. Remember when they recommended new tires went on front, now they recommend they go on the rear. The only vehicle I run at max psi are the rear tires on my dad's 3500 which usually has a gooseneck trailer or a load in it, I run his steer tires at 65 psi, 80 will beat you to death on Louisiana roads. I run other tires at pressure recommended on the placard of the vehicle unless towing. Ask 100 people you will get 100 different answers. Most tire manufacturer advise tire be inflated to auto manufacturers recommended psi for that specific vehicle.
On a car I always start at 32 front and rear and adjust from there. Some of my cars were best at 28 front and 32 rear while some liked 34/34. My Caprice wagon has 32 front and 35 rear but I haven't driven it enough to form an opinion, started it at 30/30 because that is what it had when I got it but felt mushy at times and bad mpg. I NEVER use max tire inflation unless fully loaded inside and pulling a trailer at the same time in whatever car I have. Do that on an empty 1 ton truck and you won't have any kidneys after a short time!
Hi, personally, I never use max tire inflation. According to my understanding the max tire pressure reading on the tire is an information about the max pressure the tire can bear. This does not consider driving comfort, road grip and tire wear. I definitely would follow the cars manufacturer advise and go a little bit higher (appr. 3 psi) from there to reduce tire heat up on long distance high speed travel. It may save a very little bit fuel too. If tire pressure is too high, the tire tread will bulge outwards, resulting in higher tire wear in the midlle of the tread...at least that´s what I learned some time ago... it may be different with fuel saver tires. And of course when changing tire size you have to start from scratch. The point is only, a too low pressure you may notify by the driving feeling, a too high maybe too, but to find the best compromise considering uniform tire wear... just my thoughts... Matt
Retired and tired. Seems like all of my vehicles end up with tires a few sizes larger than factory original. So I use a scientific approach. I go to the tire store of my choice...... which varies as I decide which may be cheaper or who's adds look the fanciest at the time. They put tires on, air them up, and I drive off. I usually ask the tire pressure and check it some morning while they are cool. Every now and then, or before a long trip, I check them and make sure they are close to that reading. If I had a Chrysler product, like my Dodge truck, I'd ask each mechanic, shop forman, secretary, salesperson, and the janitor how much air those fancy eco tires should have. Then I'd average it out or go by what the owners manual says.
Crownvictoria, the max pressure is calculated for use, as the maximum load weight is calculated at that pressure. If a truck tire has a 50 PSI max pressure, and is rated to carry 2200 lbs at that pressure, you can load the vehicle so that each tire carries that, and inflating the tire to that pressure ensures the tire won't overheat and fail at highway spped under that cold pressure. Which brings the other point: tire pressures are marked and checked "cold" because the tire makers ensure that it can expand under friction during highway driving to prevent overinflation failure. Boyle's Law does apply to tires.
Thanks for that, Silvertwinkiehobo! you are so right, I just checked the readings on my trans sport tires, they say max inflation pressure 44 psi or 3.0 bar. Typically I inflate the tires to 2.6 bar / 38 psi, Pontiac recommendation is 2.4 bar / 35 psi. So in fact there is not much room for incresing the pressure. Totally agree with your second point too! Thanks again, Matt
