Speedo Recalibration

[TxDoc]

"Before I let you go, I should mention a neat feature on the Chevy. If tire size or rear axle ratio is changed (not an uncommon situation on trucks), the RWAL and the speedo can be easily recalibrated using a service kit comprising a special connector and clip. First, you plug the connector into the back of the instrument cluster and touch its leads to the battery terminals to erase the original calibration. Look up the new tire size or axle ratio in a chart, which will tell you to remove certain pins from the clip. Install the clip in the cluster, and you're in business."

 

From this page:

http://www.autosite.com/GARAGE/encyclop/ency14l.asp

[Shaners]

That's interesting info.  I'd like to read more about this, but they say nothing else about this "service kit" ...  ???

 

I wonder where you get one and what is the cost?  That could be very helpful if it's inexpensive, because alot of guys change tire size...