Ford Explorer
Transfer Case Shift Motor

Explorers are everywhere, and so are Explorers whose 4x4 stopped working years ago and nobody bothered. When the owner finally needs it — first snow, a boat ramp, a muddy field — they find out the dash buttons or knob do nothing, or the 4x4 light flashes and gives up. On the older body-on-frame Explorers, the most common single cause is the transfer case shift motor. It is not the only cause, and on these trucks the wiring and the module deserve as much suspicion as the motor.

Generations and Parts

Ford changed transfer cases, motors and connectors several times across these years. Some are the Control Trac automatic 4WD type with an internal clutch pack, some are shift-on-the-fly part-time units. The motor is not universal across the range. Read the tag or the number cast or printed on your old motor before you order. The 2011-and-later unibody Explorer is a completely different AWD system with a power transfer unit and is not covered here.

Symptoms

• 4x4 indicator flashes and never comes on solid.
• Stuck in 4HI or 4LO. Steering binds in turns and the tires scrub on pavement.
• Nothing happens when you change the selector. No click, no motor sound, no light change.
• Works in summer, dead in winter. Corrosion inside the motor's position contacts is the classic Ford failure; cold and moisture make it worse.
• Binding or crow-hopping in Auto 4WD on Control Trac models. That is usually the clutch pack or the wrong fluid, not the motor. See our page on 4WD binding and crow hop.

Testing the System

Fuses and relays

Ford runs the shift motor through relays controlled by the GEM or 4x4 module. Check the 4x4 fuses in both the underhood box and the interior panel, and swap the shift relays with an identical relay to rule them out. A stuck relay is cheap and common.

The connector at the transfer case

On Explorers the connector sits low and gets packed with dirt and salt. Disconnect it, clean it, and look for green pins or broken wires right at the plug. A dielectric grease job here has brought plenty of Explorers back to life.

Listen for the motor

Key on, engine running, transmission in neutral for 4LO. Have someone change the selector while you listen under the truck. The motor should run briefly. If it is silent, back-probe the drive wires: voltage with no movement means the motor. No voltage means the relays, the module, the switch, or the harness.

Position feedback

Ford motors carry a contact plate that tells the module which position the motor is in. When those contacts corrode, the module sees a position that does not match the request and flashes the light. The motor may still run, but it stops in the wrong place. If the motor runs and the light still flashes, the position plate is the likely culprit, and the plate is part of the motor assembly.

Front hubs and axle

Depending on year, the front axle engages through either a front axle disconnect or automatic hub locks. If the case shifts and the front still does not drive, chase the front end rather than the case.

Replacing the Motor

• Select 2WD if possible, park level, chock the wheels, disconnect the battery.
• Unplug the motor. Remove the mounting bolts and pull the motor straight off.
• Look at the shift shaft position. The new motor must be in the matching position before installation. Do not force it with the bolts.
• Clean the mounting face of old sealer and corrosion. Water intrusion through a dirty mounting face kills motors early.
• Install, torque evenly, reconnect, and cycle through each range with the engine running.

Expect 30 minutes to an hour. The most time goes into fighting rusted bolts and a dirty connector.

Repair Costs

Our advice on an Explorer of this age: buy the direct-fit aftermarket motor, clean the connector properly, and do it yourself if you can get under the truck. The dealer path rarely makes sense on a vehicle worth less than the repair bill would be.

Mistakes We See Most

• Replacing the motor without cleaning the connector. The new motor works for a month, then the same corroded pins drop it out again. Clean, inspect and grease the plug every time.
• Ordering by "Explorer" instead of by year and part number. A motor from the wrong year may bolt up and still not talk to the module correctly, or the connector will not match.
• Blaming the case for Control Trac binding. On Auto 4WD models, binding in tight turns is usually the clutch pack or the fluid, not the shift motor and not a reason to buy a whole transfer case.
• Forcing the new motor down with the bolts. If the shaft position does not match, tightening the bolts cracks the motor housing or strips its internal gear. Line it up by hand first.

Keep It Healthy

Use the 4x4 every month or two. Change the transfer case fluid with the type printed on the case tag — Control Trac cases are particular about it. And while you are underneath, take a look at the transmission; the 5R55 series behind these trucks has its own well-known problems, covered on our Ford Explorer transmission problems page.

FAQ

Is the transfer case shift motor the same on every Ford Explorer?

No. Ford used several different transfer cases, motors and connectors from 1995 to 2010. Match the part number on your existing motor, and note whether you have Control Trac or a part-time case.

Why does my Explorer 4x4 light keep flashing?

The module is not seeing the position it requested. That is usually corroded position contacts in the shift motor, a dirty connector, or a bad relay. Test the motor and relays before replacing the module.

Can I drive my Explorer if the 4x4 is broken?

Yes, if it is stuck in 2WD. If it is stuck in a 4WD range, avoid dry pavement as much as possible to keep from binding the driveline.

Does the Explorer Sport Trac use the same motor as the Ranger?

The 2001-2002 Sport Trac shares the 600-926 motor with the 1998-2002 Ranger with electronic shift-on-the-fly. Later Sport Tracs use different parts.