Hello all,

Late last year I went with bigger tires on my 01-150 4x Lariat. I had the stock GY Wrangler and replaced them with the BFG 285's.

Of course since then my mileage has been off.

My question is what is the formula to see what my "actual miles" is. For example, if I reset my trip odometer when filling up and 5 days later I get gas and the odometer then reads 270 miles, how do I determine the true mileage?

Thanks,
David

 

Find the percentage difference in overall height and then add that percentage to your shown mileage to get actual. So if you increase tire height by 8% and you travel 270 miles then you've actually gone 291.6mi.

 

and to find your correct mph -

actual mph = (new tire diameter/old tire diameter) x indicated mph

 

I think it should be circumference rather than diameter, as that gives you the distance the tire is traveling with every revolution.

 

Thanks.

I've checked the GY web site and they do not list the overall height of the tire on the web site.

Does anyone here by chance have the height of the GY tire?

Furthermore I jst checked the BFG site and the data is missing there as well. So I would need the height of those tires as well.

Thanks,
David

 

The sizes for those brands are on
http://www.tirerack.com/
an advertiser of this site.

David, I guess you also know you're speeding.

 

Call me stupid but I do not see the "height" of the tire. I see diameter, but not height. Is this the same for this purpose?

 

Diameter and "height" would be the same so long as we are talking about a circle.

 

Why not just use the last column, "Revolutions per mile".
Find the (RP MIle) for your old tire compared to the new tire.