Terry Apple

Does anyone know if a 4L80E transmission on a 1994 suburban can be calibrated. I went from the factory 245/75R16 to 35X12.50X17 Toyo open country M/T''s. My speedpmeter is 8Mph off. And I'm not sure but we went on a 900 mile.trip and I think it put more miles on it than I accidentally drove. I've read and talked to people who say that it can add 10 miles per every 100 miles you drive.

tech2

if you go to a larger tire the odometer would accumulate less mileage not more.


1999 and newer allow you to go into the ebcm and choose different tire construction and sizes. Check if this option is available for your truck. a full function scan tool that can access ebcm/chassis is required.

Terry Apple

Oh ok thank you. When I change my differential gears from the factory 4:10 to the 4:88 next month will that effect the speedometer or odometer?

tech2

yes, it will need to be addressed. There may be a function in the ebcm to address this also but I have not done this so I am not sure.


there are companies who sell speedo calibration software for newer models. this may be another option. they may have a compatible product.