Reprogramming Speedometer?

[tom.boswell.79]

Changing my tires to a slightly taller tire so I could go to LTs. What is everyone's experience getting your speedometer reprogrammed? Is it worth it? Thanks.

[b1gted]

if you get the right programmer, it not only fixes the speedo, but also your shift points etc to accommodate the difference.

[tom.boswell.79]

if you get the right programmer, it not only fixes the speedo, but also your shift points etc to accommodate the difference.

is that something the dealer can do or does it need to be done by someone that specializes in it?

[b1gted]

is that something the dealer can do or does it need to be done by someone that specializes in it?

From my understanding, most dealers don't like to mess or won't mess with reprogramming because you changed the stock wheel or tire size out.

[Skelly]

From my understanding, most dealers don't like to mess or won't mess with reprogramming because you changed the stock wheel or tire size out.

 

Is it something a local shop may have? Seems stupid to spend 300+ on a programmer to reprogram it one time ...

[b1gted]

Programmer. It makes a backup of your original ECM data, then changes what it needs to. if you ever need to revert back, it has the data stored in it to do so. Once it makes the backup and changes your ECM to the new settings. The programmer is locked to the vehicle, so this isn't something a local shop could do. Your two choices are a programmer, or find a dealer that is willing to reprogram your ecm.

[Skelly]

Programmer. It makes a backup of your original ECM data, then changes what it needs to. if you ever need to revert back, it has the data stored in it to do so. Once it makes the backup and changes your ECM to the new settings. The programmer is locked to the vehicle, so this isn't something a local shop could do. Your two choices are a programmer, or find a dealer that is willing to reprogram your ecm.

 

Thanks for explaining. How necessary do you think this is? I'm about to get some 33" tires (32.8 to be exact) whereas the stocks are 32"... new tires are much wider though too

[tbarn]

From my understanding, most dealers don't like to mess or won't mess with reprogramming because you changed the stock wheel or tire size out.

CAN'T

[VinnyZ17]

 

Thanks for explaining. How necessary do you think this is? I'm about to get some 33" tires (32.8 to be exact) whereas the stocks are 32"... new tires are much wider though too

Lauras gmc puts 33x12.5 on their leveled trucks and they advertise they don't recalibrate for that size but will once they go above 34. I put 1in taller tire on my truck and via gps when my truck says 70 im about 73. Hope that helps. I did not do a programmer on my truck.

[BigBadSierra]

It depends on how much different they are I put on Goodyear Duratrac's and it only changed by 1/2 a mph so not even worth bothering for me.

 

Just FYI the gauges round it up so by the gauges it states 55 when in reality I'm going 54.5.

 

I have a good navigation GPS that shows decimal places. My actual tom Tom GPS wil show 54 to the 55 by the gauges.

 

I find the rounding little funny,