6 ply instead of 4 ply

[shooter]

Hey all; I thought I might go with the ( 30-9.5-15 ) tires for my truck, and when I asked about the tire size, the tire guy said they were 6 ply tires. Anyone else using 6 ply tires instead of 4 ply 235 75 15's ???

[Tink]

Not sure, but I think the 30s on the Blazer are 6 ply tires... ply is the same thing as load range... load range B is 4 ply, C is 6. The 6 ply tire is stronger and can handle higher air pressures... good for off-road use, where you may want to raise and lower pressure.

[shooter]

Is there a difference in ride comfort, or stiffness?

[Tink]

Not really, but if you do run them at a higher pressure then it will cause a harder ride.

[shooter]

Wouldn't happen to know if there is a weight,or engine performance difference that would be a deterent for me in deciding would you?

[Tink]

Larger tires will result in higher rpms, most noticably on the highway... but if you are running 235s now, 30s aren't much taller. I believe 235s are ~ 28.5".

[shooter]

Cool; Thanks my friend

[D-Caf]

Uhm, wouldn't larger tires result in lower rpm's? As you increase the diameter of the tire/wheel the fewer rotations the tire must make to cover the same distance (since there is a larger area of circumference per full rotation of the tire). So the plus side is lower rpm's at highway speed, the downside is more torque required to get moving in the first place.

[<-~Jo~->]

^^^ yeah and the engine will need more power to get it rolling .... you said it..

[shooter]

Damn; and I just put the K&N fipk on, and a new throttle blade in, lol. The extra fuel mileage is a plus though. I don't have a race truck, really don't care much about speed off the line. These tires are for a 4X4 crew cab, trailering and off roading, and I just want to put a little fatter tire under it. My intension with the fipk and tblade was assuming I was going to put bigger tires on it. Next will be dual exhaust.

Would I be wrong if I were thinking my speedometer will change a little with the speed being lower than true speed?

[jjwalker]

yes, it will be lower than the true speed.

Go on google and find a tire/speed calculator so you can just compensate. with that small of a difference I bet it will be maybe 1-2mph off.