I currently run 265/75/16s on my '02 Rodeo Sport, but I will be going up in size (again) to 285/75/16s this Spring. How can I get the speedometer calibrated properly to the new tire size(s), and how can I set the new shift points w/ larger tires for the automatic transmission?

Even with 265s, the shift points are off. I am using a K&N air filter and Flowmaster muffler, but those two combined should not make that much of a difference compared to the larger tires. The local tire shops say that I need to go to Isuzu to set it all up, but the Isuzu Service Dept. tells me I'm out of luck... Any help would be great!

A.M.

Here in Kansas City there is a company called Metro Speedometer, about all they do is calibrate speedometers. Possibly you have a company around you like them.

YOU NEED A DIFFERENT SPEEDO DRIVEN GEAR THE ONE THAT DRIVES THE ENG (VEH) SPEED SENSOR AND THEN YOU CAN GET IT TOO WITHIN ABOUT 3 MILES PER HOUR OF BEING DEAD ON, AND IT WILL GET THE TRANS BACK TO SHIFTING WHERE IT SHOULD , LEAVE THE TRANS CONTROL SW TURNED ON TO PWR DRIVE AND IT SHOULD BE FINE , MY TROOPER HAS THE SAME SIZE TIRES ON IT AND HAS THE TRANS POWER LITE ON FOR THE LAST 80000 MILES AND IT SHIFTS FINE TOWING A CAMP TRAILER , YOU NEED A 15 TOOTH DRIVEN GEAR AND THE SMALLEST ISUZU HAS IS A 16 TOOTH , A 15 TOOTH WOULD PUT YOU DEAD ON, JERRY

has any one tried to take the electronic route instead of the mechanical route for this fix i jsut got a dakota digital speedo interface and am going to be putting it on this weekned any one else used one of these?

http://www.dakotadigital.com/index....y_id=287/home_id=59/mode=prod/prd126.htm

I'm having the same issue after adding 3" Calmini lift and 265x75-16 tire. What was done to correct the shift point issue? Does anyone know of a place in the Phoenix, AZ area that could possible re-calibrate the computer if this is an option? Currently, my shift point is around 3000-3250 RPMs. <img src="/forums/images/graemlins/confused.gif" alt="" />

The shift points can be corrected electoniclly using a auto shift adaptor and computer re-program. I had my corrected at Dick's Speedo-n-Tach in Tempe AZ now my Rodeo shifts perfectly now and was well worth it. Dick's came highly recommened and was great to work with, and got me right in and out with no problems.