Different tires size, pro's and cons?

You can feel the difference of 69 mph compared to 70 mph?

 

My GPS gives a readout of my speed.

The only other option is to time it with an accurate stop watch, and then do the math.
Your finger has to be accurate as well. Get it off by one second and you will get a different result.

 

I dislike different sized tires with a passion, I have recently been seeing nothing but low profile steers on the front and god only knows how small on the back. Those are not truck tires.

Give me a standard 24.5 and a patch of radial capable of taking a certain amount of weight all around and leave it be.

It aint hurt none 50 or more years and I don't aim to start putting cute little wanna be tires to try and save a penny here and there. It's not proper.

 

Wear of a tire changes the actual speed ur going for example if ur speedo is calibrated with a tire that has a od of 38 inches. The new tire measures 38.3 when brand new and 37.8 when worn and needing replaced. You will start out we’re 70 on ur speedo is 71-72 on ur gps and when worn speedo says 70 but ur gps says 67-68. This is how it all works in concept ur gps is using a math formula and gps position to figure ur speed and is actually a little slow to react to speed changes. Anywho the speedo is calibrated to have a happy medium of new tire to worn and be as accurate as possible. Cars stay more accurate due to less tire od change over the life of a tire we’re as big trucks have a larger change in the life of a tire. Hope this help thru my ramblings to explain the basic concept

 

What was the truck originally spec’d with? If it had 24.5 all the way around there’s a chance the speedo wasn’t recalibrated when the wide base tires were put on.

 

By the way, the size difference does not matter to the speedo.
It is all about what it is calibrated to.

Change the tire size of the axle that the speedometer is working with and the speed readout will change.
But change the size of a different axle and it won't matter.

Right now my GPS reports a speed of 64mph while my speedometer reads a true 65.
But, my drive tires are getting near their limit at the low end. They are worn.

That means that they have less circumference than new tires, so are not traveling as far for every rotation.
The speed sensor shows that I am going faster than my true speed.

And the rim size has absolutely nothing to do with it.
I could go from a 22.5 to a 24.5 inch rim, but if I keep the circumference of the tire the same the readout will be the same.

 

Use a gps app on your phone to see actual speed. Like everyone has said tires wearing down will change the circumference of the tires which changes your speed at any given rpm. Going from 24/32 down to say 4/32 on the tread depth makes a significant difference on a 40” tire.

 

you get better fuel mileage with 22.5 lopro tires ,