http://calid.gm.com/vci/VINEntryPre.do Run your vin here and it will show your information.

Here is mine can anyone tell me what the Speedometer one is for? My Truck is at the steeler now for the reflash, and a heavy kinda tire noise from the right front at about 60MPH sound like its in 4wheel except louder, except its not the tires as they are stock.:eek:

<TABLE width="100%"><TBODY><TR>VIN: 1GCHK23264F213995

</TR></TBODY></TABLE>

<!-- Display CALIBRATION_SELS_BLOB --><TABLE width="80%" align=center border=1><TBODY><TR><TH>Selected #</TH><TH>Description</TH></TR><TR></TR><TR><TD>15141668</TD><TD>Operating system</TD></TR><TR></TR><TR><TD>15245557</TD><TD>Service cal fixes: engine combustion knock elimination/reduction at 80 to 140 Mpa rail pressure under light to medium throttle driving, rough idling and white smoking condition elimination/reduction, low speed light throttle driving surge elimination</TD></TR><TR></TR><TR><TD>15245549</TD><TD>Service cal fixes: engine combustion knock elimination/reduction at 80 to 140 Mpa rail pressure under light to medium throttle driving, rough idling and white smoking condition elimination/reduction, low speed light throttle driving surge elimination</TD></TR><TR><TD>21996487</TD><TD>Engine diagnostic</TD></TR><TR><TD>15136389</TD><TD>Fuel system</TD></TR><TR></TR><TR><TD>15282640</TD><TD>New calibration to reduce the potential for the engine coolant hot temperature telltale coming on prematurely.</TD></TR><TR><TD>15087292</TD><TD>SPEEDOMETER</TD></TR></TBODY></TABLE>

This only tells you what is available, not neccessarily what is in your truck...

Exactly what I am thinking! Just check the info for 4wheel steering - its also available! But non of us has 4weel steering, its not available for the heavy duty truck.