WE JUST HAD OUR FIRST SNOW FALL IN PA. IT SNOW LESS THE 2 " AND I PUT MY 2003 TAHOE INTO AUTO 4WD BUTTON ON. WHEN I GOT HOME ,LESS THE 3 MILES I PUT IT BACK INTO 2WD AND A SEVICE 4WD CAME ON THE DASH THAT I TO SEVICE THE 4WD.. WHAT DOES IT MEAN? AND WHAT DID I DO TO THE TAHOE?

VINCE