Ok my first post on this site so i just bought this 2008 silverado Vortec Max 4X4, its also my first gm truck ive been a toyota guy since i learned to drive, sold my crewmax to buy this silverado cause it was really good priced, the thing is that my 4wd is not engaging. i turn the dial to 4h and it hesitates for about 5 mins and then the light go the the 4h but i still dont feel or see my 4wd working. i want to see if i can tackle this myself b4 i decide for the dealer, where do i start on trouble shooting the 4wd system? New to silverado so really hope yaw can help :?: