Transfer case use

[MarkD]

Are there speed tolerances for changing from 2HI to 4HI to AUTO?  Is it different between the 1500,2500,3500?

[mka18]

Here's some info from the manual, page 2-50...  No minumum speed for shifting to 4wd high though.

 

Shifting into 4HI or AUTO 4WD

Press and release the 4HI or AUTO 4WD switch. This can be done at any speed (except when shifting from 4LO), and the indicator light will flash while shifting.  It will remain illuminated when the shift is completed.

 

Shifting into 2HI

Press and release the 2HI switch. This can be done at any speed (except when shifting from 4LO).

 

Shifting into 4LO (Use the same procedure shifting out)

To shift to 4LO, the ignition must be in RUN and the vehicle must be stopped or moving less than 3 mph (4.8 km/h) with the transmission in NEUTRAL (N). The preferred method for shifting into 4LO is to have your vehicle moving 1 to 2 mph (1.6 to 3.2 km/h). Press and release the 4LO switch. You must wait for the 4LO indicator light to stop flashing and remain illuminated before shifting your transmission in gear.

 

If the 4LO switch is pressed when your vehicle is in gear and/or moving, the 4LO indicator light will flash for 30 seconds and not complete the shift unless your vehicle is moving less than 3 mph (4.8 km/h) and the transmission is in NEUTRAL (N). After 30 seconds the transfer case will return to the setting last chosen.