Just got new tires and went from a 245 to a 265,the tire guy says I now have to take the truck back to the dealer and get the trans reprogramed?? I know the speedo/odo will be off slightly but is there anything else awry??? I should know better but he did put the tinge of doubt in my mind...

I don't know why you would have to take it to the dealer to get the Alli reprogrammed, driving it around should take care of that for you.

I can tell from my own experience with and without recalibrating it I saw no difference in driving and breaking (messing up antilock system) In my case I went with a even bigger tire too... from 245's to 285 and 315's.

I bet your speed is off by about 2-3 miles per hour at 60.
Actually going 62 -63.. You can check this with a GPS.

get a tuner to change that to get speedo in check .

x2, trans will do a bit of adaptive learning to adjust shift points for the larger tires, but your odo/speedo will be off unless you recal.

He was making it sound like it was a do or die situation. I didn't think so but I start doubting myself and what I've read here,just wanted to check with the experts.

THANKS Guys.

http://www.miata.net/garage/tirecalcold.html

http://www.4lo.com/calc/geartire.htm

I ran 265s from new on my '03 8.1/A, and 285s on '05 and '06 D/A from new and never had a problem with anything. He's misinformed. I just did the correction factor at fill ups for mileage calculation per the tire size.

Thanks again for the last 2 responses. It says 3.9% from 245 to 265, plus 3.9%,less 3.9%???? Confused again,sorry..:o:

Thanks again for the last 2 responses. It says 3.9% from 245 to 265, plus 3.9%,less 3.9%???? Confused again,sorry..:o:

Take the total miles traveled for the tank and times it by 3.9% then add it to the total miles traveled for the tank.

For example, take 200 miles times 3.9% and that is 7.8 miles. Add that to the 200 and you end up with 207.8 miles.

Or to add to the above: 200 x 1.039=207.8 then divide by gal = mpg

Thanks again....It's a wonder I made it to 41 years of age and am this stupid...

:rolleyes:

Thanks again....It's a wonder I made it to 41 years of age and am this stupid...

:rolleyes:

It's what we call at work..brain farts. Don't worry we all have them.:eek: Just some people have more than there share.

j/k
Before long you'll be helping others do their mileage calculations.;)

It's what we call at work..brain farts. Don't worry we all have them.:eek: Just some people have more than there share.

j/k
Before long you'll be helping others do their mileage calculations.;)



I am learning so much here that it's almost criminal that this site is free!:D

I am learning so much here that it's almost criminal that this site is free!:D
Shhhhhhhhhh...

I am learning so much here that it's almost criminal that this site is free!:D


I feel the same way.
Diesel Place gear and Donations here~ http://www.nicktane.com/dieselplacegear.htm

no trans reprogram. the only thing we do here is the abs system, so it knows how fast you were going. other than that it affects nothing.