so i recently replaced the tranny but while it was in the air i decided to engage the 4 wheel drive only to notice the front tires did'nt turn no matter in 4 low or high its a manual shift on the floor. you know push the button down move the handle to high or low, old school. So in 2 wheel drive and neutral i can stop the front drive line by holding on to it with my hands, but put it in 4 high or low i can't. My manual doesn't really talk about this. so what might be the possible remedies for this problem?

89 blazer 4.3 v6 not sure type of transfer case

 

so, your transfer case and front wheels aren't connecting? front driveshaft locks when TC put in 4wd, but spins when put in 2wd, while trans in park? Front axle disconnect?

 

well i'm not sure by what you mean disconnect but i bet some where something is not connecting, reason for the question spider gears u-joints ? where should i start looking?