Question about using larger than stock tire diameters

I am considering using some larger than stock BFG's as of monday, however there are two problems:
Speedo will go out of whack
Odo will do the same.

How do you guys with larger than stock rubber deal with these issues?

 

like men..realize it's off and adjust accordingly.

 

really depends on how much bigger of a tire
im running 285/70/17 and my speedo is only off a couple MPH
Odo i think shouldn't change

 

it'll change, but for the worse. the spedo is going to read slow, so naturally the driver will drive faster..for example the driver will drive 55 according to the spedo but will actually be going 57ish, therefore the odo will turn over quicker = out of warranty faster

 

yeah, neither really change significantly unless you go huge with some 35" tires or something. some people claim that the speedometer is actually a few mph slower with stock tires and claim that it's right on with 265's or 285's.

 

i just put 2657017 bfgatko's d's and the extra 1" lift is cool..with the rear tsb and 5100s at 1.75" has great look..the easy lift...also just added trd exhaust..speedo is still corrrect, odometer is off 3-4%...has great look and ride is really sweet...i have run 5-6 sets of revos in the past and just wanted to try something different...always wanted to run bfgatko's...they are definately a 4wd tire..ride is different(harder) than revos...its ok...i just decided there are too many good tires out there not to try something different...ltxat2's will probably be next in 2-3 years...keeping my fingers crossed, sc next month...and mx grille

 

With stock size (265/70/16)the speedo is off but with 265/75/16 it is spot on. I have 255/85/16 (33") then the speedo is slow but at 50 im goin 52 and before (stock tire) when the speedo said 50 I was going 48. So this makes the warranty last longer not shorter.

 

Yeah the difference is so minimal, it's nothing to really worry about. I went up to a 265/75/16 and the speedo is pretty much dead on now.

 

When I switched to 285/75/16 my speedo was reading 65mph and my GPS is showing 67mph. As far as the odometer I drove exactly 1 mile on my GPS and my truck odo was showing .9 so do the math on that one.

 

I totally agree. Same here. Having the fastest color "Pyrite Mica" I still have to go into stealth mode at times when on the superslab. <grin>

 

1. Don't confuse speed and distance. If you drive faster, you still drive the same distance.

2. I'm confused. I thought the odometer read tire revolutions. The rest of the post is based off of that assumption.

• A smaller diameter (stock) tire 265/70/16 would make 659 revolutions/mile.
• A larger diameter tire 285/70/17 would make 616.6 revolutions/mile.

The odometer would know that the stock set up went 1 mile in 659 revolutions , but the odometer would think that my aftermarket (larger) tire would have only gone 616.6/659 = 0.936 miles when the vehicle actually traveled 1 mile. Thus my conclusion says that larger tires actually make the miles rack up SLOWER than smaller tires.

Is my assumption that the stock odometer measures tire revolutions correct?

 

you are correct. speed and distance are different calculations. i am pretty sure that the odometer calculates tire revolutions. so a larger tire would calculate to less of a distance.

 

That's correct. With a larger tire, you are covering more feet per rotation, so you will actually travel a longer distance over time without it actuallt showing up on the odometer.

 

so is there anyway to actually correct the speedometer- - ie change speedometer cable gear or reprogram the system- This is my first taco - have been a f250 guy forever so have alot to learn on this thing

 

You are pulling his _ _ _ _ aren't you?

 

Bang - now that's what I'm talkin about. Now this is a fun thread, good dialogue.