gear swap=ABS light+speedo off GRRRRRR!!!!!!

[BOTTLEDZ28]

So I did a gear swap at the same time I did my RCX lift. Went from 3.42 to 4.56 and now the freaking ABS light is on and the speedo is off about 20 mph! The speedo being off has caused a side issue too! When the speedo sees about 100mph, the governor kicks in and the truck falls flat on its ass.

Is there some type of speed sensor gear in the trans that I can change to correct the speedo and ABS light? I do plan on doing the 0411 swap but I wasnt going to get into that until next year. If tuning the black box ecm is the only way to correct the speedo and ABS issues, then I might as well just do the 0411 swap now.

Also, I had a buddy check the truck for codes today to see if it had any stored and it had a U1041 code. (Loss of EBCM/EBTCM Communications.) Could this be related to the ABS light being on? I only ask because I do have an intermittent transmission issue where the converter unlocks once in a while while cruising on the highway. When it does it, its raining out. Not sure if changing the gears will fix that since the truck will be running at a slightly higher RPM now. Basically closer to where it was stock.

 

[bluex]

It has to be adjusted with a tune or a handheld tuner

 

[BOTTLEDZ28]

handheld tuner as in one of those Hypertech power programmers? myh buddy tried changing it with his Snap on scanner but it didnt work. His scanner had a bunch of different tire sizes that he could apply to the ecm and the one closest to my tire size didnt even change the speedo. I figured it would make it closer but nothing changed. We both have no idea what the change even does in the scanner.

 

[95C1500]

or DRAC or VSSB mods?

 

[df2x4]

or DRAC or VSSB mods?

For older trucks yes, according to Z28's sig though he has a '98 which would require a tune.

 

[95C1500]

you're right, I forgot it was pre-96 trucks

 

[bluex]

handheld tuner as in one of those Hypertech power programmers? myh buddy tried changing it with his Snap on scanner but it didnt work. His scanner had a bunch of different tire sizes that he could apply to the ecm and the one closest to my tire size didnt even change the speedo. I figured it would make it closer but nothing changed. We both have no idea what the change even does in the scanner.

Ya I believe a hypertech programmer can do it. The last one I had could anyways. You need to change both the tire size and gear ratio to get the speedo back to reading correctly.

 

[BOTTLEDZ28]

Ya I believe a hypertech programmer can do it. The last one I had could anyways. You need to change both the tire size and gear ratio to get the speedo back to reading correctly.

Im just going to do the 0411 swap now. I cant see paying all that money for one of the handheld programmers when I can spend the same money if not less and do my 0411 swap this year.

 

[bluex]

Im just going to do the 0411 swap now. I cant see paying all that money for one of the handheld programmers when I can spend the same money if not less and do my 0411 swap this year.

I dont blame you there. The 411 will give you more tuning capability and options anyway.

 

[BOTTLEDZ28]

0411 is in and the speedo is perfect now along with no ABS light.