Tire width changes over time

[bigrig]

Hey FRF'ers check this out. After too many beverages on memorial day I decided it was time to post a random thread to the tire forum. In the picture below, a stack of used 35x12.50R17 Toyo MTs (about 3000 miles) against a new set of 37x12.50R17 Toyo MTs.

I found it interesting that the old tires were wider overall. Can I assume that riding on low pressure over extended periods of time and jumping the truck stretches the rubber so the tire becomes slightly wider?

I sort of expected that rubbing and tire clearance issues would be reduced over time since the tire would become smaller when the rubber wore off, but this adds a different dimension to consider since the tires appear to get fatter over time.

 

[two0seven]

What is the measured width of the new vs old?

 

[Ruger]

I don't buy it.

 

[Deleted member 17706]

I don't buy it.

Neither do I. I just switched my tires. My 37s were still bigger than 35s.

 

[Deleted member 17706]

Maybe the 35s in the picture above are 13.5” wide. More matter just doesn’t magically show up. You ought to have less matter because you wore down the tire tread.

 

[two0seven]

After studying the picture some more you can definatly tell that the used tires are sticking out more look at the gaps between the treads on the left vs the tread on the right being much closer together between tires. There appears to be some sideways stretching of the tires.

Wonder if OP has woken up from his drunken slumber yet.

 

[squeak]

Hey FRF'ers check this out. After too many beverages on memorial day I decided it was time to post a random thread to the tire forum. In the picture below, a stack of used 35x12.50R17 Toyo MTs (about 3000 miles) against a new set of 37x12.50R17 Toyo MTs.

I found it interesting that the old tires were wider overall. Can I assume that riding on low pressure over extended periods of time and jumping the truck stretches the rubber so the tire becomes slightly wider?

I sort of expected that rubbing and tire clearance issues would be reduced over time since the tire would become smaller when the rubber wore off, but this adds a different dimension to consider since the tires appear to get fatter over time.

It's the bulge in the sidewalls that makes them appear wider.

Sent from my SM-G950U using Tapatalk

 

[bigrig]

Sorry for the delay, it has been a rough morning.

I measured the width and the old tires are indeed 12.5" wide. The new ones are 11.5"

I will measure them again after I mount them on the wheels, perhaps the stretching that happens once the tire is seated on the bead will push out the sides a bit.

 

[Deleted member 17706]

After studying the picture some more you can definatly tell that the used tires are sticking out more look at the gaps between the treads on the left vs the tread on the right being much closer together between tires. There appears to be some sideways stretching of the tires.

Wonder if OP has woken up from his drunken slumber yet.

Yea, I see some wear too. But 3000 miles on the tire is nothing. Those TOYO MT are robust. I couldn’t imagine hard off-roading would make a tire expand in its mass to that degree.

I went to Baja in March (from Tecate all the way to Cabo). @RDFTS had a slow leak in one of his tires after doing 5000 plus miles driving from Missouri to Baja and back to Missouri. When the leaking tire was exchange for one of his new full spares, the leaking tire—that was put on a couple months before the Baja trip and had less than 10,000 miles on it—had less tread and looked smaller than one of his new spares.

It should be noted he had KO2s.

 

[Ruger]

https://en.wikipedia.org/wiki/Conservation_of_mass