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2nd Gen Non-Engine/Transmission Speedometer calibration

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Engine/Transmission (1998.5 - 2002) Need a refresh

2nd Gen Non-Engine/Transmission Back in a dodge

I ordered a superchips spedo calibrator. According to the company it's supposed to work on my truck. I get it, update it, hook it to the truck, and my truck isn't an option. The company is sending me a new one. They think the wrong one got shipped. I've been doing some looking around and nearly every other site says it's not compatible with my truck. In fact, it appears the only option is the hypertech inline unit.

I know the Smarty can change the speedo. Is that the only one able to flash the computer? I know the dealer can too but trying not to go there.
 
You should say something about your truck like the year and transmission. 1998.5 and later use the ABS sensor in the rear differential for the speed. Changing the speedo calibration is a software parameter change. Older trucks use a gear and cable from the transmission. You change the gear to change the speedo calibration.
 
You should say something about your truck like the year and transmission. 1998.5 and later use the ABS sensor in the rear differential for the speed. Changing the speedo calibration is a software parameter change. Older trucks use a gear and cable from the transmission. You change the gear to change the speedo calibration.

Truck info would be helpful. It's an 02 cummins 6spd. I was able to borrow my buddy's snap on scanner and do it that way. I'm going to return the flashcal.
 
Very small nit to pick. '98 and later; my '98 12V uses the rear diff sensor.
There's a rear sensor for the ABS but I thought the 12V had a mechanical speedometer and instrument cluster. You could unplug the rear diff sensor and see if the speedo works.
 
There's a rear sensor for the ABS but I thought the 12V had a mechanical speedometer and instrument cluster. You could unplug the rear diff sensor and see if the speedo works.
When I installed the 19.5" TY303s, I originally used an Abbott and later switched to a TruSpeed to adjust the speedo. Both of them sit between the VSS in the rear and the CAB (Controller, Antilock Brake) under the hood; adjusting the frequency of the differential signal the VSS produces. (Technical detail: the wire from the VSS to the CAB is twisted pair for noise immunity.) The CAB then sends a normal single-wire signal to the PCM.

The speedo is fed from the VSS. The wire cuts I made in the line to the CAB made the speedo a little wonky when they corroded or got loose. And later when the speedo was intermittent, I finally traced the problem to the VSS' pigtail, where one of the wires had broken inside undamaged insulation.

I suspect this change happened when the 47RE was introduced.
 
Interesting. My 98.5 gasser used the rear diff ABS sensor for the speedometer. The calibration was done using an engine tuner connected to the OBD2 port.
 
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