Tire Guy Was in A GOOD MOOD

[luvrbus]

JohnEd, truck tires are measured on the sidewall measure the sidewall to outside edge of tire multiply by 2 then by 2 and you have it  11x2 = 22   22x2 =44  and believe it or they didn't teach me that in school lol

good luck

[JohnEd]

Thanks Clifford.....you always cut to the chase.LOL

[Melbo]

We are parked on the bank of the Mississippi River and the bottom half of the tires look like a BIG smile (the top half looks like a big frown).  Gotta run 7 miles tomorrow in spite of the invention of the internal combustion engine. Then it's time to get the inner tubes out of the tires for a float.

I will post some pictures when I get a chance.

Melbo

[robertglines1]

When matching tires I always used 3/4 inch in circumference allowance difference (runout). Must maintain equal air pressure.  Bob

[artvonne]

  With the advent of a cheap handheld IR gun, the answer to the question rests right in your hand. Short of measuring the inflated tire with something accurate, and even that means little after its mounted on the vehicle, if the difference is small, the actual running temp is going to tell you more than anything else. It likely impossible to expect the pair on a side to run perfectly equal, to the degree, but there should not be anything wildly different.

[Ed Hackenbruch]

The inside tire will run hotter, less air gets to it to cool it. if one side is running in the sun that side will be hotter than the other side. When all is said and done, you could have 4 different temperature readings on your duals. I have found 30 degrees or more difference from inside to outside tire. I have a lot more faith in my Pressure Pro than i do the temp gun because i can check my tire pressures as often as i want while going down the road. I use the temp gun when we make a stop to check tires, bearings, brakes, etc. but for some reason the wife refuses to jump out and do it while we are traveling.

[jackhartjr]

'Scuse me', am I right in thinking that if you bought 11 tires, (I run a Scenicruiser, it has 10 plus a spare) would I not be hard pressed to find several in that batch that are 2/32's or more different?
Jack

[Ed Hackenbruch]

I think you are right Jack.    When i bought 4 tires for the rear i was talking to the tire guy about balancing them. Now you would think that the tires would be real close to each other but he told me that only about one out of 100 was perfectly balanced when it came out of the mold. One of mine was perfect, the other 3 each took different amounts to become balanced.

[chev49]

Of course i'm an odd ball, and our business wholesaled tires for 45 yrs. but i am not afraid to have slightly different steer tire circumfrence, and as eugene john said, its the circumfrence that counts.. A mechanic i talked to yesterday told me that on a 4wd you have to have exact same tire sizes... and i told him that you can have 4 completely different sizes, as long as the tire circumfrence is the same... in fact you could have 4 different wheel sizes on a car, as long as the circumfrence is the same... i had to show him with a plate that the  same  outside tire curcumfrence equals same axle revolution.  This doesnt address the width,  heat or stability issues, just something l learned in the '70's driving on the sand dunes... All drive tires on trucks and busses should be close circumfrence...not to mention the DOT guys complain loudly if you get a small chunk out of your tread around here.. and don't dare have a strip of asphalt close to your wheel stud, or they will call it a crack (even if you wipe it off) and have u sit for 2 hrs waiting for another wheel...

[JohnEd]

'Scuse me', am I right in thinking that if you bought 11 tires, (I run a Scenicruiser, it has 10 plus a spare) would I not be hard pressed to find several in that batch that are 2/32's or more different?
Jack

\
You are correct from what I am hearing.  2/32(1/16) is well below the 1/4 (4/16) limit.  The other point that seems to be being made is that the "short" tire will wear at an accelerated rate even though the taller tire will run hotter due to its carrying more of the load.  I pondered exactly why a big rig trailer would have some tires with usable tread when most were bald...all the same brand....model....miles of use in the same identical conditions  and lot.  I heard recently that they cut mounted tires to the same diameter with a hot knife or grinder.  We did that on our race cars (puffery that) and I did it on my street cars but we did it to get the tire absolutely round. We also did it with the tire mounted to its "forever" position and with the studs marked.  Round AND the equal diameter should be worth the time....only the service charge is hanging out there.

John