I have a 99 ZR2. When i push the 4 high button the light flashes, the transfer case shifts into 4 wheel drive, but the hubs don't lock. Same thing with 4 low. Is it vacuum or electric or what? What locks the hubs? its cold and my garage isn't heated, so I wanted a little info before I go crawl around in the snow.
Thanks

 

hubs??? no hubs on this, case has to engauge front driveshaft and then front axle has to engauge, the assembly for that in on the passanger side axle by oil pan. u may have a vacume problem or the cable on the axle is bad, look in the diy section for testing info. got to get up on all 4 and check it all out, let us know what u find and we can help alot more