Questions with Tire pressure

[Torqueranger]

I am running 235/75/r15 on both of my explorers but my questions is what pressure do you guys run with that size tire on 15x8 rims ??? Cause I am having problems with wearing the outside tread out ..

Here is the tire I am using

 

[Dave 1955]

Might need a alinement.

 

[koda2000]

I run 32-35 PSI cold. No offense but Good Year Wranglers would be my last choice for Explorer tires. If you're wearing the inner & outer edges first your tires are under inflated. of course the inner/outer edges on the front tires will always wear more than the center. that's why you should rotate front-to-back around every 7,000 miles.

 

[Maniak]

I am running 235/75/r15 on both of my explorers but my questions is what pressure do you guys run with that size tire on 15x8 rims ??? Cause I am having problems with wearing the outside tread out ..

Here is the tire I am using

If your wearing the outside edge on both sides of the tire then your either doing lots of high speed cornering (doubtful with an explorer) or your tires are under inflated.

The correct way to set the pressure with new tires is to do the chalk test. Just get to a big empty parking lot, Draw a line across the tire, drive forward a bit and then look at the chalk. You want it to wear off evenly. If the center wears off first you have too much air pressure. If the outside wears first you don't have enough..

Otherwise, it really depends on the tire construction BUT, in general low to mid 30's works well on 235x75r15 tires as a starting point.

~Mark

 

[Torqueranger]

No offense but Good Year Wranglers would be my last choice for Explorer tires.

Why is that ????
The reason I am asking because I plan on buying my wife some new tires

 

[deweyville65]

I run 30-32 psi on my 235's, but on the factory 7" rims.

 

[DjDom]

Why is that ????
The reason I am asking because I plan on buying my wife some new tires

I ran Wranglers on my truck for most of it's life without any problems..
They are a bit rougher of a ride than other tires, I must admit.

 

[koda2000]

I find the Good Year Wranglers don't ride very well, don't handle very well and wear out too quickly. I prefer Michelin LTX M/S. they ride well, handle well and wear like iron. Granted they're more expensive initally, but worth it in the long run.

 

[Dave 1955]

He said he was just wearing out the outside tread..not the inside also.
But I'm sure he will get a alignment with new tires..but you would be surprised at the amount of people who wont.
The chalk thing does seem to work..I did it when I put my 31' on..good tip.

 

[dcdyd]

Wearing out one side of the tire is definitely the alignment issue. You should set the pressure according on what is on the label on the side of driver side door. On my 98, it says 30 psi code pressure for both front and rear. Ans I usually set the pressure between 30 and 32 psi.

 

[koda2000]

He said he was just wearing out the outside tread..not the inside also.
But I'm sure he will get a alignment with new tires..but you would be surprised at the amount of people who wont.
The chalk thing does seem to work..I did it when I put my 31' on..good tip.

it's not clear to me whether the OP is referring to both outside edges on one tire or just one edge, but if in fact it's just one edge, then yes he has an alignment problem.

 

[jadatis]

I am running 235/75/r15 on both of my explorers but my questions is what pressure do you guys run with that size tire on 15x8 rims ??? Cause I am having problems with wearing the outside tread out ..

Here is the tire I am using

That tire has profile blocks that cover a part of the sidewall, so stiffens it , and leaves less sidewall to flex.
I suspect the Firestone tires that courced the Ford Explorer/Firestone affaire, in wich more then 100 people died because of roll over accidents, mostly courced by blowing tire, to have such kind of profile too.
Those tires need higher pressure to give it lesser deflection.
This is all my own conclusion.
In the affaire 26 psi was used all around, and later highened to 30 psi , so probably that 30 is enaugh to cover the lesser deflection allowed.
But to be shure you have to calculate it.

Nothing wrong with these tires , as long as you use high enaugh pressure, wich lower the comfort and gripp though.

That needed tire -pressure can be calculated, but the given maximum load of the tire then needs to be lowered , mayby even by 10%.
Will show 2 pictures of such a tire in compare with a "normal" road tire, and an even worse off-road tire that needs even to substract 20% of the maximum load.

This is the compare and now the tire with even larger sidewall flexing reduction wich needs probably to reduce that 20% of the maximum load.

 

[Torqueranger]

The tire wear in on both sides of the tires .. Also I just had alignment done ..

 

[Flash]

Wear on both sides of the tyre almost certainly means under inflation.
Don't, as mentioned earlier, take notice of the tyre placard.
As also mentioned earlier, 100 people died before Ford changed the placard.

About 36psi would be good and higher if under load.

I don't like Wranglers because they feel "squishy" like they're under inflated but more inflation doesn't help.
I've used Firestones but didn't roll over but then I had 38psi in them.

I use a laser pyrometer to measure temperature across the tread and set my pressure that way.

 

[my98nnj]

I always ran 30 cold, never had a wear issue.

 

[Flash]

I always ran 30 cold, never had a wear issue.

What tyres are they?

 

[SoNic67]

I am running also 30psi on OE tires (Wrangler RT/S). They run rough even at that PSI, but they don't wear un-uniform.
Some level of wear on 'outside' of front wheels is expected even if the alignment is 'perfect' - this is because the front wheels are not parallel (toe in) per the factory angles to help with stability on straight line driving (this is valid for any car out there).
That's why we need to rotate the wheels.