Having a problem with 97 2500 5.7l 5 speed truck. If I put the truck in any gear and start to let out clutch it will move with the idle of the truck but as soon as I give it any gas something give out and you hear a grinding noise and the truck starts moving also shifting from gear to gear got hard as well

 

Check fluid level in the trans first...... Might wanna drain some out, and see if anything rude comes out with it.

Is the t-case (if you have one...) firmly in 2wd?