Hello All,

I have a 2002 Screw. The stock tires were P265/70R17. I recently replaced my stock tires with BFG LT265/70R17 tires. I also have a SuperChips M/T. I wanted to set the computer for the new tire size. My new tires measure 30.25 inches. I did not measure my old tires before I had them replaced.

Is there some one out there that has the stock P-metric 275/70R/17 tires that will measure the back tires for me? I just want to know if there is any change in tire size...

TIA,

Brian

 

Mine is out in the parking lot now, but according to the calculator, http://www.onlineconversion.com/tire...conversion.htm the 275/70/17 is 32.2" tall
it also puts your current tire at 31.6"

then you have to factor in air pressure and loaded weight of the truck.


hope this helps...

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KingRanch-02, you changed tire sizes part way through your post - from 265 to 275. Assuming you are interested in the 265/70/17, which is what I have on my truck, I just measured them at about 31" - properly inflated and no appreciable load in the bed. Hope this helps.

 

Yeah, I should have proof read my post. I wanted the actual, real world measurement of the P265/70R17 tires.

Sometimes I am my own worst enemy.

I had thought that the LT tires would be bigger than the P-meteric based on calculations and BFG's web site. But it would seem that they are smaller.

Thanks for going to the trouble of measuring your tires!

Hope to maybe return the favor someday.

Brian

 

Your speedo will still off.

I put in my actual tire hieght and kept bumping it down in 1/4" increments until it was correct.

Local PD with a radar gun gave me a hand. Got it correct after the fifth pass.

FYI,

After I got it set.....my Garmin GPS was just a hair off. In case you or a buddy has one. If I ever set it again, I'd use the GPS to set it and call it a day.

 

Tire sizes have a mathematical calculation to determine theoretical dimentions including overall diameter. The actual tire lines have variances, but P and LT have nothing to do with the size. I suggest looking up the old tire and the BFG specs for actualy overal diameter to determine your difference. Or, a more accurate way is to use a GPS/radar gun. The speedometer usually off at highway speeds by a couple MPH on every vehicle I have used a GPS with.

 

I know that mathmaticly, the P-metric and the LT metric should be the same size (31.6"). Goodyear lists the Wrangler RT/S at 31.6" and BFG lists the A/T ko at 31.8".

I did not measure the rolling diameter of my OEM tires when I install the Superchips M/T. I selected "stock" for tire size. After I had the BFG's installed, I measured them to find the rolling diameter as referened my Superchips.

Because I never actually measured the stock tires and I no longer had them, I had hoped that some one would. I wanted to know if there was a real world difference in the rolling diameter of the two tires.

I agree that the speedo is off. I will attempt GPS or RADAR verification.

Thanks again,

Brian

 

With the SuperChips MT, you do not need to know your original tire size, so if you're unsure if you need to adjust your speedo, just input the new size and reprogram the computer.

 

I just used the Microtuner to adjust tire size and you are correct, you do not need the old tire size.

Measure your current rear tire height and enter it in the Microtuner at the closest 1/4 inch increment.