1994 full size blazer which has a maual floor shift for the transfer case. when I try to shift from 2hi to either 4hi or 4lo the gears grind. the owners manual says to be moving forward 1-3 mph when shifting to 4lo and it still grinds. I can get it to go in but it grinds. It is even worse coming out of 4lo back to 4hi. The transfer case oil is to the top of the plug hole. any suggestions? Thank you.

 

my suggestion would have been check the case oil but since you've already done that you may want to get the opinion of a mechanic. i encounter no such sounds when shifting my truck.

 

It is my best knowledge that you dont want to stop in N on the floor shifter. You must make these moves from 4hi to 4lo and back with one fast smooth motion ortherwise I know it will grind. It says so in my owners manual (although myne is a 87s10 blazer).