High air pressure in tires

[Caster]

So even on my truck calling for 60 in front and 80 in the back I should run that with no load? That's the max the tire will take.

 

 

 

On the subject of heavier trucks, I'm much more inclined to back off a bit.

 

E load range tires max inflation is 80 PSI but unless you are regularly hauling heavy loads, no way I'd run that much in the rear.  The front is different because the engine and tranny are weighing on them a lot more than the back. This is very important in diesel cause that thing is HEAVY.  I tell people in your case, unless you haul heavy loads, equal them out.  Run 60 in all four.  If you wanna haul a load of gravel or a couple dozen sheets of drywall, bump them up.  

 

Now, this is only conjecture from doing this for years, but I do not recommend running E load range tires much below 40 or so.  Most E load range tires have tall sidewalls and they were never meant to sag and flex like a standard load tire.  I have seen many of them wear prematurely from doing so.  A guy not long ago just HAD TO HAVE some 10 ply tires.  Well, first off, there's really no such thing for 99% of passenger vehicles and light trucks.  They are 10 PLY RATED.  Read the tire.  It'll say 10 PR but in fine print it'll say 5 or 6 ply tread with a 2 or 3 ply sidewall.  YMMV.  

Plys harken back to bias ply tires where the number ply actually meant something.  Now, materials are exponentially better and more can be done with less.  They didn't have rayon cord, steel belts and kevlar weave and all that crap.  

Anyway, this guy HAD to have them for a standard 1/2 ton truck (dumbass) but he couldn't stand the hard ride of 50 or 60 PSI and certainly not the 80 max, so he ran 35 like his door take says.  They lasted around 30K.  Should have run MUCH longer on a tight front end and properly rotated.  He listened second go around and got over 60K out his standard load tire.

 

Moral?  It's no different than hunting or reloading.  More ain't always less.  Match the components to job.  

 

 

And while I'm on the subject, people and these Z rated tires just kill me.  What a friggin joke that crap is.  When's the last time you ran 160 MPH continuous?  Most z rated tires have a tread wear of squat.  A michelin Pilot may have a 600-700 tread wear but crap like pirelli P zero and others have like 250-300.  They are NOT worth money.  It's all in your mind people.  Unless you're on the track or drive like a fool.  No one needs them things on a Mustang they depend on to get to the office.  ....Unless you just enjoy forking over money twice as much and then...by all means.  Us tire guys are laughing all the way to the bank.

Edited April 30, 2016 by Caster

[Sidecarist]

I drive a 2500HD with a diesel. Door placard says 65 front 80 rear. For day to day driving I run them all at 65, rotate them every 5k and got 65k out of the last set nice even wear.

When I hual the trailer the rears go to 80. If I don't the handling is awful. Empty if I run them that hard the rear skips and chatters.

This is my 4th HD truck and I learned this from following the advice of a good tire guy. He's seen more tires than I ever will...

Wife's car I run the door placard pressure and we are expecting 70k+ from those tires. Again I am following the advice of my tire guy.

The moral is in a good tire guy and follow his advice.

[NoBanStan]

Just keep inflating, it'll let you know when it's too much :D

 

Wait, we're in modern America ***warning, do not inflate tires until they explode, it is hazardous to your health and could cause injury or death***

[2.ooohhh]

I never use the door placard as anything more than a general guideline for stock vehicles. That said, NONE of my vehicles are close to what you might consider stock. I put new tires on and run a chalk test in combination with a non contact thermometer.

 

The chalk gets me close to the correct pressure, once I have the chalk wearing evenly across the tire I know they are contacting relatively evenly. Then I switch to the thermometer checking inside, middle, and outside temps. This verifies that while the entire tire is making contact that all the tread is being used as evenly as possible for traction. If the outer and inner are both lower or both higher I adjust the pressure in half pound increments. If just the outside or just the inside is hotter or cooler than the rest I check the alignment. Last set I set up was a set of a set of Bridgestone RE-71R they are technically a track tire, but I run them on the street. Since they are track tires they come with NO warranty for tread life. I still expect 24-30k out of the set due to the light weight of the car and the compound's wear thus far but to achieve that I have to actually monitor and verify my air pressures. (no .gov mandated tire idiot light in vintage BMWs)

 

$13 IR thermomoter

 

Good tire guage($42) If you spend the money on a good tire gauge and use it often it will pay you back several times that in tire longevity.