Shifting on the fly

[Murf]

2003 Duramax with Allison.

When shifting on the fly from 2 to 4wd iits making a grinding noise and then engages - is this common or what?

Thanks, Murf

[Lenl]

I have a 2001 and mine never makes any noise during the shift in either direction, thinkin you gots a problem

[drwoodchopper]

Not normal. Were your reel wheels spinning by chance, then it could happen?

[More Power]

At what speed are you engaging/disengaging 4WD?

You can disengage at any speed, but I always slow when engaging (less than 20-mph). I can feel/hear it engage (clunk sound). And, I test it a bit before adding power. (Especially after twisting a shaft in two pieces on Lil Red :D )

Jim