Does a lunchbox locker disengage at all in 4WD?

Alatex

Alatex

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This may be a dumb question, but I tried to search without clear answers. I ordered a powertrax no-slip for my Dana 30 since I have a Dana 44 and LSD in the rear. Will the lunchbox locker stay locked at all times in 4wd even in times with little or no throttle?
 
Last edited:
it will still unlock.

What unlocks it is when you turn, the outside wheel wants to spin faster than the inside wheel. This pushes the entire locker assembly ahead of the carrier, releasing the pressure applied by the crosspin to the ramps. Once this pressure is released, the drive gear can move inward, releasing from the side gear teeth, unlocking, and letting the outside wheel go as quickly as it wants.

For this to happen though, you need to have good traction under all your wheels. If the traction isn't good enough for the ground to drive the outside tire hard enough to unlock the locker, it won't unlock. If traction in the rear is bad and one or more rear wheels are spinning, it won't unlock.
 
freedom_in_4low said:
it will still unlock.

What unlocks it is when you turn, the outside wheel wants to spin faster than the inside wheel. This pushes the entire locker assembly ahead of the carrier, releasing the pressure applied by the crosspin to the ramps. Once this pressure is released, the drive gear can move inward, releasing from the side gear teeth, unlocking, and letting the outside wheel go as quickly as it wants.

For this to happen though, you need to have good traction under all your wheels. If the traction isn't good enough for the ground to drive the outside tire hard enough to unlock the locker, it won't unlock. If traction in the rear is bad and one or more rear wheels are spinning, it won't unlock.
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So basically in 4wd it shouldnl stay locked at all times when it is needed and shouldn’t unlock at odd times when a locker is important?
 
Alatex said:
So basically in 4wd it shouldnl stay locked at all times when it is needed and shouldn’t unlock at odd times when a locker is important?
Click to expand...

right, when you need a locker (because a wheel is spinning), it's because the carrier in the crosspin is driving the drive gears through that ramp, which pushes them apart and locks the teeth into the side gears.
 
When it arrives, check it carefully. Mine showed up open box from Amazon, and had the wrong parts in it. Waiting for the return to go through so I can buy it again - hopefully a factory sealed box will arrive this time...
 
Alatex said:
Will the lunchbox locker stay locked at all times in 4wd even in times with little or no throttle?
Click to expand...
I have the exact setup you're gunning for (Dana 44 rear, LSD and a Dana 30 front with the powertrax no-slip) and can tell you from experience that as long as you're applying even a very small amount of torque to the front diff in 4WD, you will be locked. Period.

The only time this locker will act like an open diff is either in 4WD with absolutely no torque applied (the jeep literally not moving or possibly coasting with no throttle) or in 2WD.
 
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