Replaced battery now speedometer acting up

Speedometer sits a zero when stopped but accelerates two times faster than I'm actually going. So at 40mph, it maxes out at 90.
On an '06 Columbia with a cat 15.
Anyone have any ideas?
Thank you!

 

Will do! Thank you.

 

Checked both in line fuses and they were good. Cleaned all the contacts for the wires and still nothing.
The truck is acting like it's governed now too.
Very strange.

 

I replaced one because it was leaking and bloated. The others were fine so I didn't mess with them. My cruise has never worked out of park, so I can set my rpm to charge the air tanks if needed but can't set for speed. Could this have reset the computer and be showing kilometers per hour maybe? It almost seems like that

 

Thank you, I'll give that a try. I wouldn't either but it actually adds up. I've driven without a speedometer before for a year and I got good at knowing my speed based off rpm. If the needle reads say 65mph but I'm actually going about 45mph, that's close to kph if not spot on when converted. I don't have any idea why it would do this though after replacing a battery. It also seems governed now when I'm up to full speed in 10th gear, the truck wouldn't add speed no matter how far the pedal was pressed, no added turbo, nothing... just like a governed company truck.

 

I would like to add, there were no insane sparks when I changed it out so I don't believe any harm was done like blown fuses or relays etc.
And the truck functions like always other than the speedometer and odometer.
I really appreciate the help though and I'm glad this will be posted here for anyone else with this issue should it arise because anyone looking for solutions about their truck realize the struggle of finding them online for big trucks.

 

Resolved, so the ecu was blank. It didn't have any information about the speed, what gear it was in, etc.
Actually had to have the ecu reprogrammed with the speed information. Had to figure out the gear ratio, count the teeth on the back of transmission, and the revolutions per mile for the tires to find the number to enter into the ecu.
Don't know why it happened from a simple battery exchange but hope this helps someone else in the future.