My '00 Blazer 4X4 won't shift into 3rd. Been having a few problems lately with the 4WD as well, it sometimes won't stay engaged and the lights will blink on the push buttons. Blazer has 270,000 miles on it so really don't want to stick any $$ into it if it would be the tranny. Looking for some easy fixes first. Also, I tried taking the fuse to the 4WD out to see if they were related somehow and the battery light came on and all my gauges went haywire. Take it easy on me...I'm a female with limited mechanical knowledge but am married to a mechanic