tire pressure for 225/35/19?

[00000]

i know there are tons people using 225/35/19 tires in this forum
wat is your tire pressure?

[crossbow]

Search for posts by Toyoguy. And list your load rating of your tire.

[Stretch]

Crossbow, the post you're asking him to search for is stickied.

The problem is that his tire size isn't listed in ToyoGuy's list of recommended tire sizes and pressures.

Why?

Well, because 225/35/19 is not a safe tire size to run on the Mazda6. Even with a reinforced sidewall, the load rating is only 88. Without, it's a dismal 84.

Sorry man, there is no safe tire pressure for those tires.

[Tire Guy]

Put the max the tire says (probably 50 psi) and say a few Hail Marys.

[Stretch]

Might as well order a spare set of shocks, too. They don't last long with rough-riding tires (even with stock springs), and I think a 35 profile at 50psi certainly qualifies as brick-like.

[00000]

thank you all for the great advice!

[mazda6guy]

Originally posted by 0@Jun 9 2005, 12:45 AM
thank you all for the great advice!

[snapback]427433[/snapback]

I'm curious as to what "load rating" is? Does it mean the lower the load rating, the higher the chance that you could suffer a blowout if you take a corner to hard of hit a pothole? Or does it mean that your tires could blow if you have extra weight in your 6, such as a full load of passengers and luggage?

What does it mean and is it overated? By that I mean, by going from a 93 load rating to a 88 load rating, does this increas your chance of a blowout my a huge percentage (say 5-50%) or is it an insignificant increased chance, such as 0.5-4%?

[crossbow]

[BangHatch]

hey cool... my forum colors are different.. i didnt know it could be changed..

[Tire Guy]

Originally posted by mazda6guy@Jun 9 2005, 09:21 AM
I'm curious as to what "load rating" is?* Does it mean the lower the load rating, the higher the chance that you could suffer a blowout if you take a corner to hard of hit a pothole?* Or does it mean that your tires could blow if you have extra weight in your 6, such as a full load of passengers and luggage?

What does it mean and is it overated?* By that I mean, by going from a 93 load rating to a 88 load rating, does this increas your chance of a blowout my a huge percentage (say 5-50%) or is it an insignificant increased chance, such as 0.5-4%?

[snapback]427580[/snapback]

Gather 'round, kids. Time for a history lesson.

Before the early '90's, the European Metric Sizing System looked like this:

205/60HR16

Notice the speed rating (H) was placed before the R(radial) designation. Unfortunately, this system gave no information about load carrying capacity of the tire. That is, how much weight could this tire support and at what air pressure? You had to look at the microscopic print on the sidewall of the tire to find that out. This could potentially be important because certain sizes came in extra load rating.

For example, the 185SR14 came in standard load and Load Range C (extra load). Lots of regular European cars could use that size, but the Volkswagen Vanagon (which came with that size, too) needed the extra load tire. Probably due to some misapplications which resulted in tire failures, it was decided a new sizing system was needed.

Enter the ISO Metric System. This sizing system looks like this:

205/60R16 91H

Notice the speed rating is now outside of the size with the load index (in this case 91). The two characters (91 & H) together are called the service description. The 91 corresponds to a load rating on a load rating chart. Since it's not really necessary for you to know what 91 equals, this easy system allows customers to quickly identify if a replacement tire meets the original equipment requirements. You should never go lower than the original equipment load rating. For the Mazda6, the minimum is 91 (even though cars equipped with 17 inch have a 93, other similar models in the lineup have 91, so the lowest denominator is acceptable in the case of the Mazda6).

To satisfy everyone's curiousity, here are the load indeces mentioned:

91 = 1356 lbs @ 36 psi
88 = 1235 lbs @ 36 psi
93 (reinforced) = 1433 lbs @ 42 psi

The Mazda6 requires minimum 32 psi. A 91 load index tire can carry 1224 lbs @ 32 psi. That covers you, another passenger and a full tank of fuel. If you put luggage, subwoofers, 5 passengers, etc., you're supposed to increase the pressure in your tires which will increase the load carrying capacity of your tires (more air = more load capacity).

But, guess what? If you have 88 load index tires, you have to have 36 psi just to carry the same weight as the 91 @ 32. Put some friends, luggage, etc., and now they are overloaded. Overloading creates lots of heat in the tire, which can result in catastrophic tire failure. It will definitely lead to very short tire life. So, there's no good reason to put an 88 load index tire on your car. It's not b.s., all those numbers on your tire are there for good reason. Your safety. Ok, class over!