The truck is an '01 F-250 4X4 and the sticker on the door calls for 265/75/R16 and the truck currently has 285/75/R16. Are the 285's taller or wider? If they are taller, how far are they throwing the odometer off?

 

The 285s are taller then the 265s, I love how they give my 250 sits on the 285s but I am not sure how much they throw the odometer off.

 

A little of both, your 285s are an inch taller and an inch wider. 1-3mph difference...maybe.

 

Many thanks. That is the information I was looking for. I am going to take the GPS out in the truck on a 10 mile run to figure the exact difference.

 

Use this link. http://www.miata.net/garage/tirecalc.html

 

[QUOTE=NEWT92]Use this link. http://www.miata.net/garage/tirecalc.html[/QUOTE]
Geat tool there. Thanks.

 

Here is another one..http://www.csgnetwork.com/speedocalibcalc.html

 

The 265 is 31.65" in diameter.

The 285 is 32.83" in diameter.

Your speedo should read 3.73% lower.

I just recently went from 265/75 to 285/75 on my '02. My speedo went from reading high to reading exactly correct.

I just turned 100,000 miles indicated. Makes me wonder if I should have 3700 more miles on my engine warranty...

 

i am running 315/75/16 and my speedo is only off by 4-7 mph off depending on the speed i am traveling

 

Go here and use the info that others have posted.

http://www.ricksontruck.com/speedometer.html

 

Same deal as me.