Start at the sending unit on transfer case. Check for metal filings on tip, loose connection on wiring. Then the VSB, should be to left of glove box inside of dash. White plastic case about the size of a pack of cigarettes. You have to remove glove box to get to it. If it need replacing you can find the pinout to reprogram it for tire size changes. My 94 was reset to 3:73s to offset 285's with 4:10's.
"The Constitution is not an instrument for the government to restrain the people, it is an instrument for the people to restrain the government."
-Patrick Henry
A5150nut
2006 K3500 D/A
94 6.5 4x4 5spd Sold