Posted by Steve in ID on April 30, 03 at 22:21:30:
In Reply to: Need help with conflicting info about tire size recalibration posted by ChicagoMike on April 30, 03 at 18:26:36:
What MattR said. Going from 245's to 265's on my '98 K1500 fixed a speedo calibration issue from the factory. My truck is absolutely dead-on at all speeds. Verification includes an AR state trooper's radar gun, the troopers calibrated speedometer, calibration rollers at a speedo shop in AR (I took traffic school), and two separate gps receivers. Make sure you're not as accurate as you desire before spending the money at a dealer. To digress, are you sure you speedo is correct now??
Steve
: I have a 1999 Tahoe with the 5.7 liter engine and P245/75R16 tires. I'm planning on switching to LT 265/75R16 tires in the very near future. I've read several posts about recalibrating the engine/transmission control module and the ABS control module when changing tire sizes. The service department at my local Chevy dealer where I have all my work done says they can recalibrate the ABS control module but the engine/transmission control module does not have a tire size calibration function. I've read previous posts where the writer says they had the engine/transmission control module recalibrated. Did the writers have 95-99 Tahoes/Suburbans or 00-03 Tahoes/Suburbans? For a 1999 Tahoe, what exactly should I tell the service mechanics to recalibrate on the engine/transmission control module?