i just got my lift and tires. I am wondering what tire pressure is recommended for everyday street/highway use? I have Pro Comp All Terrains in 315/75/16. Please help

 

Can't anyone with 35 inch tires tell me what tire pressure you are running for everyday driving in the city?

 

35 front and back -

Mike

 

Are they LT (Light Truck) tires? What load range? What is the "max cold" psi listed on the tires?

My Michilen LTX A/T's are a LT type, load C, 50psi max cold tire.

I run 50psi all around when loaded down, when empty ... 45psi front, 40psi rear for a comfortable ride.

LT Load C, 50psi max cold, 6 ply
LT Load D, 65psi max cold, 8 ply
LT Load E, 80psi max cold, 10 ply

 

I just talked to a friend recently who has been a tire monkey for Costco for the last five years...he says for everday use AT's should be at 40 or even 45 PSI if you want to maximize their tread life.

 

Well, I did the contact patch test. The one where you run your tires threw water to see if the entire width of the tire is touching the road. Well i had to air down to 25 PSI in the front to get the water completely acrross the width of the tire and the rears are at 20 PSI and not even the entire width of the tire is touching the ground. I still have 3/4 of an inch on both sides of the rear tires before they come in full contact with the road. I am stumped? And the top of the tires still have a curve, they are not flat.

 

Likely difference would be made with wheel size

Are you running stock wheels?

If you rolling wide tires on narrow wheels, you will be pulling the sides in a little and thus pulling up the outmost edge of the contact patch.

For street use, you likely want more air pressure so you have less drag

Less drag equals less heat, tire wear, and better mileage

Only air down for the trail.

 

Hey man, sorry, I just saw this thread. I had the same problem and made many posts about it almost exactly a year ago. I spent lots of time on the phone with Pro Comp, and lots of time out there with a tire pump, guage, and chalk. I have a 2001 F-150 4x4 ext. cab with the stock 17's. I had the Pro Comp AT's in a 33x12.50x17 installed. To get everything running "right" I have been running 34 front, 24 rear for a year now and all seems good though I admit, I hate the idea of not being able to run at a higher pressure, and the tires are real sensitive to temp changes due to pressure increase / decrease of more than 2 lbs. or so. I figured they'd eventually wear flat, but so far I'm not seeing much tread wear. I rotate about every 8K mi. I love my ProComps but hate the bowed tread. Probably due to squeezing 12.5" wide meats on a 7.5" rim. Oh well, at least they are waaaay more "stabe" than the ConiTrack 31's I had put on my 98 Ranger 4x4. I'd also like to try out some of the Trxus AT's.

BTW, these damned ProComps weigh about 65 lbs. a pop and they are only like 28.25" tall rather than a true 33" but I guess that's pretty common with all 33's.

P.S.S. at this setting I get wear all the way to about half of the outer lug...I worry about too much heat, resistance, poor mileage, etc...but to the touch these tires stay really cool, and I haven't noticed the mileage change much...probably better if anything but I Superchiped at the same time I got the new meats.

-AR

 

Thank you so very much for the responses. And no i am not running the stock wheel, i thought that was dangerous in itself. Well i have 16X8 wheels. And Jackel, are you sure that your tires only measured 28.25" tall? My 35's measure just at 35 inches. And your rear tires seem really low at 24 compared to the front tires. So these tires are really that sensative to weight?

 

It seems so...the front end is so heavy, the rears have to be at 24 or even 22 to run the same. I may be off, but Im pretty sure they are smaller than 29" tall...I have my MicroTuner programmed at 28.25" (took from measurement) and they are dead on. I could probably get another inch if they had 55 lbs. in them.

 

Maybe ProComp designed them so they do not run on the outer lugs?

 

Sorry man, I'm retarded...just found this post I made a while back.

"Well, I just scanned again, after clearing and I still get the same code. I measured again. My height at rest (on the ground) is 31.125". My top side rim to sidewall distance is 6.75", and my bottom side is 5.875", so this leads me to believe my tires are 32" tall off the ground and I have 7/8 th. of an inch of "squish" all around the tire. This makes my total "functional" height 30.25", which is what I have it set to. If I set the value to 31", my speedo is off by about 4 mph. at 50 mph. Just out of curiousity, what is the stock value of a 265/70R17?"