4:11 richmond gears(how to fix speedo)

[TornadoSS]

Originally Posted by pouncer72

The odometer is run by the BCM, which receives its signal from the wheel speed sensors, not the transmission (which the speedo does). You can go so far as to unhook your speedo completely, and your vehicle mileage will still increase on the odometer. Tested and proven on my own car, multiple times, while I was figuring out how to wire speedo into a 4L80 swap

Interesting! That must be a little known fact around here! Good to be part of a forum with knowledge. Thanks for the info! :beer:

[fldrummer]

Originally Posted by pouncer72

The odometer is run by the BCM, which receives its signal from the wheel speed sensors, not the transmission (which the speedo does). You can go so far as to unhook your speedo completely, and your vehicle mileage will still increase on the odometer. Tested and proven on my own car, multiple times, while I was figuring out how to wire speedo into a 4L80 swap

Um, maybe, but how do you explain the fact that my odometer put more miles on than I actually drove before I had the speedometer corrected after my gear install?

[pouncer72]

Originally Posted by fldrummer

Um, maybe, but how do you explain the fact that my odometer put more miles on than I actually drove before I had the speedometer corrected after my gear install?

That's a good question, but a I said, the BCM does not care what your trans speed sensor says, which is what the cluster reads as mph.

[Higgs Boson]

Originally Posted by fldrummer

Um, maybe, but how do you explain the fact that my odometer put more miles on than I actually drove before I had the speedometer corrected after my gear install?

because you were driving faster than 88.

[fldrummer]

Originally Posted by Higgs Boson

because you were driving faster than 88.

Funny... If anyone doesn't believe me, just change your gears, leave the tune alone, then drive down your local interstate highway. Keep an eye on your trip odometer as you pass each mile marker and tell me what you see.

[Higgs Boson]

Originally Posted by fldrummer

Funny... If anyone doesn't believe me, just change your gears, leave the tune alone, then drive down your local interstate highway. Keep an eye on your trip odometer as you pass each mile marker and tell me what you see.

so you did this with gears and what wheels and tires? are you confident that the mile markers are accurate? try it also with a gps unit.

[fldrummer]

Originally Posted by Higgs Boson

so you did this with gears and what wheels and tires? are you confident that the mile markers are accurate? try it also with a gps unit.

I'm pretty confident the DOT's engineers & surveyors have the technology and know-how to accurately measure and stake out their mile markers around here, especially when the roadways are fairly flat and straight as they are here... My wheels and tires are stock, so that's a non-issue as well.

[pouncer72]

Its also possible that the early and later cars do it differently. All I know is what I experienced on my own car.

[bada450r]

ok i think a tune is in place,,,,,,,what tunner should i get?

[DandD]

I don't want to side track this thread but I have a question for you pouncer72, did you get the wiring figured out for the speedo with the 4L80E, as I am doing that swap myself this winter. If you have a diy on here and could direct me to it that would be great. I have put the 3.91 gears in my car and my speedo is off by 7mph, I'm just living with it for the time being.

[pouncer72]

Sent you a pm

[DandD]

Thank you I appreciate it.

[SUX2BU]

Originally Posted by pouncer72

No, they wont. Speedo has nothing to do with odometer, in this car.

Originally Posted by pouncer72

The odometer is run by the BCM, which receives its signal from the wheel speed sensors, not the transmission (which the speedo does). You can go so far as to unhook your speedo completely, and your vehicle mileage will still increase on the odometer. Tested and proven on my own car, multiple times, while I was figuring out how to wire speedo into a 4L80 swap

You my friend are incorrect. The wheel sensors are used for stabilitrak and ABS.

The transmission speed sensor is what the computer reads for the speedo and odometer.

[pouncer72]

Originally Posted by SUX2BU

You my friend are incorrect. The wheel sensors are used for stabilitrak and ABS.

The transmission speed sensor is what the computer reads for the speedo and odometer.

I don't have one. I can completely unplug my transmission controller (Stand alone) and take a video of the mileage increasing while the speedo reads 0 mph if it will make you feel better.