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Hello,
i am going to install larger tires(265/75r16) on my truck to replace the stock 255/70r16's. i have heard that the speedometer will be off approximately 5 mph. is there a gear to change or is the speedometer all electronic and needs to be reprogrammed? btw, i have a 4.2 v-6 and 5-speed.
It electonic controlled. The dealer can reprogram it (not sure if they all do it) or you can get a Diable/Hypertech type programmer and do it yourself. Although that isn't much of a difference in tire height difference. I wouldn't bother.
I did the same tire change. My speedo is off by 10%. I'm trying to figure out how to calibrate it ATT. I have a '98 F150, 4.6L with the 4R70W tranny, and am told that the programmers (Diablo and Superchips) only work on a digital speedo. Is the output of a 4R70W digital? If so, then the programmers should work?? If the output isn't compatible, then how do we adjust for tires and rear gear changes???
No, 97-98 cant be reprogrammed. As far as I know. Gears you can do but they kidna $$$. Only thing that I have found thats resonable is this thing Superlift has. its called TruSpeed. It installs "in-line" to the odometer. like $200. I also hear of people putting in a gear box or something?? not sure about that. But i know TruSpeed works. Starting in the 1999 year the reprogammers work.
I didnt mean odometer. Just check out what superlift has to say about it:
The TruSpeed module installs in-line with the factory electronic speed sensor and converts the wrong speed signal into the correct one for your vehicle's new tire and/or axle gear ratio combination. Because the signal is altered at its source, all speed-sensitive vehicle systems will receive the correct speed data, which restores all proper functions.