Tire Pressures

Here's a dumb question folks?
My summer tires are P215/70R15.Toyota says fronts at 29psi,rears at 32.Thats What I have them at in the summer.
I now have my Bridgestone Blizzacks on for Winter. 215/70R15.Are the recommended tire pressures from Toyota the same for my winter tires?
Thanks for your attention!Any help is appreciated!

 

29/32 only applies to the OEM spec. tire.

The OEM tire should be a P-metric...P215/70/15/97.
Can you confirm?
At 29/32 psi, it gives you an inflated load capacity of 1,488/1,554 lbs.

The Blizzak are euro metric...215/70/15/98.
For 1,488 lbs of inflated capacity you need 32 psi.
For 1,572 lbs of inflated capacity you need 34 psi.

 

Generally I put more air pressure in the front tires. The weight is up front with the engine, unless you have a reason to put more pressure in the rear.

 

2WD truck? I would run 29 front, 27 rear. For winter only. If you do any hauling go back to 32psi in rear.

 

I put whatever the engineers at Toyota recommend. (per the placard)

 

Thanks everyone for your replys!Youve been a huge help!

 

Yes the size I quoted is the Oem size.

 

Most folks need pressures that promote good tire wear over load capacity.

Start with the placard rating and do a chalk test. Then adjust pressures 1# at a time, repeating the test, until just right.

 

285 75 17 's E loads

Did the chalk test on mine, 32 front 31 rear with a full tank of gas and the matching spare in the bed.

I also have an ARB front bumper and run with my front plate skid on all the time.

 

The number on the door jamb is for best ride with factory tires and no cargo in the truck. The number stamped on the tire is for hauling heavy loads. Somewhere in between will give you the best fuel mileage and still have an acceptable ride. An extra 5 psi can mean 2-3 mpg. If driving off road or where traction is needed about 1/2 the number on the door jamb. Of course this only applies to factory tires. If you're using a different size or if you're running LT's instead of P's you're working off the charts and need to experiment.

But the number on the door jamb is a good place to start for general driving. Most LT tires are rated for 80 psi with heavy loads. On a Tacoma you don't need anywhere near that. Closer to 40-45 PSI is about the most you'll ever need with LT tires on a Tacoma.

I tend to run my tires a little closer to the max listed on the tire than what is on the sticker on the door for a couple of reasons. I actually haul stuff in my truck fairly often and I don't have to take time to air up before loading my truck and let the air out again after I'm finished. Most people who have more than a driver and passenger in their trucks don't have enough air in the tires and that can be dangerous. Plus it gives me a little better fuel mileage. But there is a fine line between too much air and just right. Too much and you wear out the center of the tread before the outside. I've always gotten 55,000-65,000 miles out of most tires so I must be doing something right.

 

The tire placard is GVWR x DLF.

 

All good!Thank you guys for your help!It is appreciated!

 

I was wondering if one can use a non contact IR non contact temp. gun to read temps across the tread to determine air pressure. Has anyone tried with this?

 

Low 30's for pressure. Do the chalk test to be the most accurate.

 

Don't know what the chalk test is?Please explain

 

A test to determine your 'optimum' tire pressure; for your particular weight and it's distribution.

The tire placard is basically GVWR x DLF(dynamic load factor).
For example;
3rd gens have a engineered DLF of 1.535
GVWR is 5,600 lbs
Recommended tire pressures have a load inflation capacity of 8,596 lbs(4 tires x 2,149 lbs) for P and euro metric tires.
8,596/5,600=1.535

If using an LT, the DLF is 1.396.
4 tires x 1,954 lbs=7,816 lbs
7,816/5,600=1.396

Anyway...
The popular method is to chalk the tire, drive forward a short distance on a flat surface and look for lateral wear pattern.
Less chalk on the outsides; needs more pressure.
Less chalk on the center; needs less pressure.

There is a more advanced method, that takes into account DLF.

https://www.4wheelparts.com/a/tire-wheel-package-guide-tire-pressure-checker

Let the chalk tell you

You can also “calculate” your tire pressure with the chalk method. This involves coloring a section of your tire with chalk to see how much tread is making contact with the ground. Start by finding a flat road surface. Concrete is actually the best choice, but you can also do this on asphalt. Make a mark with soft chalk that goes all the way across your tread. Then, gradually drive your truck forward about 50 feet and then backwards 50 feet.

Analyze the chalk on the tire. If the chalk is only worn off on the center of the tire, reduce the tire pressure slightly and go through the process again. With the adjustment, you should see the chalk wear off more broadly. Keep making tiny adjustments in the tire pressure until the chalk wears off evenly and all the way across the tread.

You will have to complete this process for each of your four tires. Once you’ve found the right street pressure, add 10% to all four tires. Then, measure the tires and add pressure to balance them. As explained above, you need to measure from the wheel to the ground. Start by balancing the profiles of the front tires with each other. Then, balance the front tires again with the rear tires. Always adjust the tires with the smaller profiles by adding air.

The advantages and disadvantages of this method are the same as those involved in the second method above. If you go through the process correctly, you end up with the ideal tire pressure. But, this method is tedious and there’s a reasonable chance that you will make a mistake.

 

Dam! Physics is mind blowing,till I have to do the chalk test !Ha!But I'm going to do it!Running 32 in the front,and 34 in the back,with my blizzacks.Ride is great!These tires love snow.Thank you very much for this explanation!Ive copied it,and will share with friends!Im a novice gearhead and love learning this intell!

 

I will report back on my chalk test !Thanks guys!And especially slipknot for that great explanation!