Tranny Or Transfer Case?
 

Someone help! i need advice! i got a 82 Chevy 1/2 to 4x4! just recently i notice that when my truck is in 4Low and im in reverse if i gas it it make an ugly gringing sound, so thats how it started now ive notced that when im Drive its also starting to Gring when the RPMs get high! does anyone know if this is my Transfer case goin out? Tranny going out? Bad U Joints? or something simple? any advice will help! thx!!!:chevy: