01 2500hd wont engage 4x4 til high rpm.

[sanders71]

01 2500hd, 8.1L allison auto, push button 4x4. wont lock in until its about 2000 rpm then will release just fine. Just not sure of where to start looking for the problem. Actuator on the axle or in the transfer case or something else?

[j cAT]

Originally Posted by sanders71

01 2500hd, 8.1L allison auto, push button 4x4. wont lock in until its about 2000 rpm then will release just fine. Just not sure of where to start looking for the problem. Actuator on the axle or in the transfer case or something else?

what is the fluid condition of the transfercase. color ?

[sanders71]

Originally Posted by j cAT

what is the fluid condition of the transfercase. color ?

Looks like a frothy tan color. The truck has over 200k on it and to my knowledge its never been changed. With that kind of mileage, what is the best fluid to use?