My newly acquired used 2004 HIHY has "4WD" label on the back lift gate. Other HIHYsI have seen say "AWD." What is the difference? I looked in the manual for instructions on how to engage/disegage 4WD drve with no luck. Is it different or the same? If the same Is it automatic engage/disengage or fulltime? Thanks to anyone who answers!!! from 86 year old in Spirit Lake Idaho.