For GMC Sierra pickup trucks back in the old-body style late 1990s (1996, 1997, 1998) (not the new-body-style and more recent from 1999 onwards), what features made up the Z71 package? I always thought the off road package entailed four wheel drive, but in looking at classifieds, some Z71's seem to be 2WD, not 4WD. I suppose the suspension was different. How about the differentials? What else?
As explained here, lots of people add aftermarket Z71 stickers to their truck to artificially increase the value. If the truck truly is a Z71, it would be listed on the RPO ("regular production options") sticker, which I believe is in the glove box for the Sierra.
The real Z71 package had the following (copied from the link):
- Z71 Off-Road suspension
- 46mm twin-tube high-pressure gas-charged shocks
- Skid Plate Package with a frame-mounted shield
- GM segment-exclusive automatic locking rear differential that provides added grip when you need it
- Available Z71 Appearance Package: 18" aluminum wheels, body-color mirrors and door handles, body-color grille with chrome insert, and Rancho® shocks
Here's a different source for a different answer.
This seems to refer to the late 90's models and lists a different suspension and some skid plates. They do specifically list the differential as being a standalone option, and I've seen (Toyota) pickups marked as off-road but only had 2WD, and it was FWD too. Again, check the RPO sticker to make sure it really is a Z71 and not just an aftermarket sticker on the side of the truck.