My Hijet has a 4x4 button on the dash, no lever between the seats. No light has ever come on in the instrument cluster to tell me it was engaged. When the button is in the on position (out) I never really noticed a difference in the way that the truck drove (mostly driving on pavement). I began to question if the 4x4 was working. I changed all the vacuum lines and verified voltage to the vsv (?) under the passenger seat. Good vac a the solenoids and good voltage. Decided to jack the truck up on all 4 corners and put the truck in gear. The first time I tried it the rear wheels spun but not the front, put the truck in neutral turned on 4x4 put in gear and low and behold all 4 started spinning but still no light on dash, guessing it's burned out(?). So here is my question...what is the proper procedure for engaging 4x4? Have truck in neutral, hit button, put it in gear and go? or do you shift on the fly?