I ran through the steps to update my wheel size in the BCM, PCM, and TCM modules when I changed wheels and tires from 18" to 20". No issues at all. Later on browsing through the FORScan spreadsheet I ran across a "tire size" related field in the ABS module (760 -02 -01). I tried changing the value from a (1= 17/18) to a (2=20). Seemed logical since I now had 20" wheels. Immediately after I wrote the new value, this caused multiple errors in traction control, hill descent control and PAM / IPAM modules pop up. I restarted the truck and none of the errors went away. I quickly set the value back to 1= 17/18. Can any one explain what this ABS field is for and why it freaked out when I changed it from 1 to 2?