4340 Shifting in/out of FWA

[saskatchewan]

I have a 1995 4340 with a forward/reverse shuttle transmission. I have notice that occasionally when trying to shift from FWA to 2WD, the transmission will not disengage from FWA.
I have to either move a short distance forward and reverse or reengage the FWA shifter several times before it will disengage and make the familiar clicking sound which indicates the FWA disengagement.

Usually I just have to move the FWA shifter to the 2WD position and move in a couple of meters in the opposite direction of travel to get the FWA to click off.

I notice this unwillingness to disengage is more pronounced after carrying a heavy load in the FEL - but not always.

Is this a symptom of problems to come or just the nature of the FWA shifting mechanism on the mechanical transmission?

Any insights appreciated.

 

[Renze]

The front axle runs 3% faster than the rear wheels. This is to be able to make a turn in 4wd mode, because the front wheels make a wider turn than the rear wheels.

So, when you're driving, there will be this 3% speed difference causing friction in the clutch, that makes it not disengaging. When you hit the brakes, or hold the throttle, the speeds of the shafts will synchronise and hte clutch will kick out freely.

 

[saskatchewan]

Thanks, but let me restate to see if I understand how to ensure disengagement to 2WD?

To disengage easily I need to move the shifter to the 2WD position, then move in the opposite direction for a couple of meters - then apply the brakes (tap the brakes briefly)?