Help with Speedometer adjustment.

I've just had a go-around with my company shop about this. All of our fleet is set at 63 (yeah I know) but actually only manages 59-60 on GPS and radar signs. Most of our fleet is Freightliners with Detroits but my assigned truck is a Sterling with a Cat. I requested a speedometer recalibration (which I'd gotten done in my previous FL) on the Sterling but was told by the tech that Cat software doesn't have an adjustment for drive tire circumference or revolutions/mile like the Detroit does.

I call BS, anyone know for sure? Its a 2005 A9500 with a C11 ACERT.

 

if u can get me the tire size, make and model of tire, and rearend ratio or last 6 of vin i can get you dip switch settings. and as far as warranty goes, they will use ecm mileage as it is supposed to be more accurate if it is close to being out or is out by a little

 

OFF, OFF, OFF, ON, OFF, OFF, OFF, OFF, ON, ON

i have attached the instructions and a picture of how to do this.. i don't know if you have a new style or old style speedo head. if its way off when u calibrate it set then set the switches the opposite way.

i have also attached the spec 400 sheet that shows what to set the dip switches at...

 

I was first!

Glad it's fixed!