Toyota Tundra Front Differential Actuator 41400-34020

This is the electric front differential (axle disconnect) actuator for 4WD Toyota Tundra 2007-2021 and Sequoia 2008-2022, all engines. It replaces Toyota 41400-34020 and aftermarket 600-420. The actuator bolts to the front differential and slides a collar that locks the front axle shaft to the differential, so the front wheels only receive power when 4WD is selected.

When it fails, the truck will not pull in 4HI or 4LO even though the transfer case shifts, the 4WD indicator flashes, or the front end stays in two-wheel drive while the dash shows 4WD. Water past the connector and seized internal gears are the usual causes. Before condemning the actuator, check the fuse, the connector for corrosion, and whether the transfer case is actually shifting.

To replace it, raise and support the front, remove the skid plate, unplug the connector, and unbolt the actuator from the differential housing. Catch the gear oil that drains out, clean the mating face, and install the new unit with a new gasket or sealant. Top off the front differential with the correct gear oil, then cycle 2WD to 4HI a few times and confirm the front driveshaft is driving the wheels.