I just bought a 1989 chevy half ton 350 2wd 5 speed and i just noticed when i put the truck in reverse and when i start to let out of the clutch and the truck starts to roll the shifter literally slides itself out of the reverse slot making a grinding noise as its doing it. I worked the shifter a little bit and finally "unbinded" it and it finally stayed in reverse. Is this anything I need to be concerned about. Im totally new to chevy trucks. Thanks. Justin.