Differential lock solenoid

[AlexS]

If anyone could help me understand it would be appreciated. I have a m1094 fmtv, runs and drives great.

When I was fixing my CTIS system under the passenger side kick panel, I also noticed it had a “differential lock” solenoid in tandem with the fan air clutch solenoid on my truck. I traced the line and it enters the front axle next the to axle breather. The solenoid operates when the mode button is activated for the “off road mode”. Does this actually lock the front axle or is it part of the 50/50 power distribution. I’ve looked high and low through the manuals and on this site and can’t find anyone mentioning it. I know I have a very oddball truck.

I’ve attached a picture of the air line from the solenoid. The one line is a axle breather and the other is an air supply from the “differential lock” solenoid.

If anyone has any idea to prevent me from opening my front axle to see what it’s doing, it would be great.

Thanks much folk

 

[Ronmar]

It locks the power divider, which is basically a center differential between the axles, like the center diff in the transfer case is a differential between the front and rear axles on a 4X4(or a 6x6). Basically when not in mode if you lift any single tire, all the torque can escape thru that one spinning wheel. When in mode, with the transfer diff and the power divider diff locked, you would have to lift/spin 3 tires(one on each axle) to loose all your torque/thrust…

 

[AlexS]

Thanks for the response!

 

[aw113sgte]

I'm away from my computer and truck, but if I remember right, those lines are vents, not diff locks? There is a 1/4 line to the power divider on the middle diff, not sure about the lock front to rear out of transfer case.

 

[Ronmar]

I'm away from my computer and truck, but if I remember right, those lines are vents, not diff locks? There is a 1/4 line to the power divider on the middle diff, not sure about the lock front to rear out of transfer case.

The center differential lock in the transfer case (goes from 70/30 AWD torque split to 50/50 4WD) is accomplished directly by the transmission when mode is selected. The TCU outputs a signal to power that second solenoid under the dash that feeds that 1/4” line to the power divider differential to lock it up.

 

[Keith Knight]

Jack up all the wheels on jack stands and engage different modes and see what happens.