After checking the tires on my 4 Runner and reviewing Rich's threads as well as other sources on the subject, it looks like I have classic indications of both under inflation - heal/toe wear - and over inflation - center tread wear - at the same time. They do have 43K on them so is this just due to the miles or do certain types of tires have inherent wear issues. These are Bridgestone Blizzark snow rated (per CALTRANS & CHP standards) tires.
They own the snow by the way.

 

Do you run them year round? Snow tires are made of a softer material and running them in ambient temps over 40-50 degrees can make them wear very irregularly.

 

Yes I do run them all year. They are supposed to be a highway tire as well but have the correct symbol on the side wall to get though a chain check point.
Also forgot to mention that alignment was done when shock & struts were replaced ~7-8 K miles ago. Everything feels tight in the front end as well. My shop would have made an issue of it if it was not.

 

Ah, the mountain peak with the snowflake... I know it well. I ate a set of those in less than 20 K miles. You are doing better than I was, and the rubber is soft on those - so they are not a long-lasting tire. That's not to say you can't improve things in regard to tire wear. I learned (the hard way) that these front-end guys that work on cars are not experienced with a 4500-pound nose, and even less so with the solid axle of 4X4. They frequently don't even have the equipment needed to do a proper job with our behemoths. All my front-end work is going to be done by the truck shop from now on.

 

Rich,
I have been using a shop in Redding that specializes in large rigs. Buses, motorhomes and semi trucks. They do good work but they are not a cheap date.
That being said the specs that I have from my last alignment on the F250 are similar to those you have posted. I did have improved stability from wandering when I increased front tire pressure to 65 psi, but I am still playing with it. Don't drive it that much so any adverse tire wear has yet to surface. The issue at hand was on my 4Runner.

 

If you want a no-BS way to check for proper inflation:

- Drive the truck until the tires are fully warmed up (10 minutes at 55mph does the trick easy enough).
- Take kids sidewalk chalk and draw a dark straight line across the tread.
- Drive forward for several revolutions until the chalk starts to wear off.

If the chalk wears in the middle first, you're over-inflated.
If the chalk wears on the outside first, you're under-inflated.
If the chalk wears evenly, you are properly inflated.

This is your HOT inflation temp. Once you get the hot inflation to wear the chalk evenly, let the tires cool for about an hour. Then come back and check the air pressure again. This is your COLD inflation temp.

Write them down and keep them handy. Check your cold inflation periodically.

For towing you'll want rear tires inflated to the specs on the door. If you aren't towing, you can let a little air out for comfort, but the chalk test isn't the best idea for the rears. Back end is extremely lightweight compared to the front, and you'll end up running very low pressures. Plus when you throw in a load or hook up a trailer and forget about your air pressure, you're now severely deflated and can run into rapid tire failure. Keep the pressures up in the rear and rotate regularly to even out the wear as best as possible.

Chalk test has worked pretty well for me on the fronts because my cold inflation pressure is usually fairly close to the specs on shown on the door sticker (within 10 psi). It does vary a bit when you change tire brands.


As for alignment, your best bet is to find the one person in town who actually knows what he's doing. You can go from one shop to another, one machine to another, and they will all tell you something different. Ask around for recommendations, you'll find the guy eventually.

 

^^^^^
Great advice Thanks! Reps sent

 

4Runner - that tripped me up. Sorry. It's my understanding heel-toe damage can be underinflation, camber, or a combination of both.