This video is an overview of an internal fix
on the Xdrive transfer case servomotor, also known as transfer case actuator. This fix
applies to the 1st generation BMW X3s. First This fix will be of interest to you if your
vehicle has simultaneously illuminated 4×4, Brake and ABS warnings lights on. You may
also here a clicking noise from under the car ever time the engine is turned off. Remember to work safe and work smart. Work in a well ventilated area, protect yourself
from injury at all times…. …and attempt all work at your own risk.
Your workshop should be well ventilated and have a hard surface if raising or jacking
up a vehicle. Remember to think about your own safety and the safety of others when making
repairs or modifications to your vehicle. Even if you don’t feel qualified to do this
work, watching the video will give you a sense of the repair, and the necessary parts and
equipment that will be needed if you decide to have the job done by a professional BMW
workshop.Before you begin, consult your owner’s manual….or the appropriate repair manual
for your vehicle. Hi, my name is Charlie Burke from Bentley
Publishers. What I have in my hand here is an xDrive servomotor. It came out of our 2007
BMW X3, first generation X3. It’s got a couple of connectors on it, it’s mounted to the transfer
case using four bolts. The transfer case is in the middle of the car mounted below the
driver’s side. Pretty straight forward to get to this thing out.
This BMW X3 had three dash warning lights on. The 4×4 light, the ABS light, and the
brake light. It also made a loud clicking noise every time we turned the engine off.
So we knew the noise was coming from this servomotor, or more specifically from a plastic
gear inside this servomotor. BMW sells this servomotor as a complete unit
and it’s quite expensive. Since our car had high mileage on it and it was also out of
warranty, we decided to make an internal repair on this servomotor. The good news is that
a plastic gear is available from the aftermarket. This plastic gear can either crack or wear
out and it is mounted inside the transmission of this servo motor. So today we are going
to show you how to remove the servomotor, get this gear out, replace it, and put the
servomotor back in. You won’t loose any gear oil when you take the servomotor out or very
little gear oil and you’re not going to need a scan tool to reset fault memory or reset
adaptations. So let’s show you how to get this thing out, on the work bench and make
the repair. Thank you. Here are the tools we’ll need to get servomotor
off the transfer case. A 10 mm open end, a 13mm socket with extension
and ratchet, an 18mm open end wrench and 18mm socket, an e10 Torx socket, a 10mm driver,
and a small flat blade screwdriver to aid in unlocking the two harness connectors.
With hand and eye protection fitted, and the key removed from the ignition, let’s get the
vehicle in the air. Position the lift arms directly under the
four hard rubber jack pads. We do not recommend raising the vehicle if any of the jack pads
are missing. Be sure all vehicle doors and lids are closed. Do not raise the vehicle
with any one in the car. Warning –
Make sure vehicle is stable and well supported at all times. Use a professional automotive
lift or jack stands. A floor jack is not adequate support.
With the vehicle in the air, position a tall jack stand directly under the transfer case.
Raise the jack until the weight of the transfer case is supported.
Now we’ll need to lower the transfer case crossmember. it is bolted to the vehicle floor
using four bolts and a bushing thru bolt. Using a 13mm socket remove the four bolts.
Use an 18mm socket to remove the bushing through bolt.
With all bolts removed, lower the crossmember and allow it to hang freely out of the way.
Next remove the heat shield bolt and gently bend the heat shield down and out of the way.
Disconnect the servomotor harness connectors. You will need to release the connector locks
on the plastic connectors to remove them. Using a E10 torx socket, Remove the four bolts
holding the servomotor to the transfer case. The top bolt is the hardest to reach.
With the bolts removed, wiggle the servomotor and pull it off the transfer case.
With the servomotor on the bench, use a T25 torx driver to remove the four bolts holding
the motor to the motor case. Carefully slide the motor assembly off.
Next is the trickiest part – prying off the seal cover. You’ll notice that the cover is
peened to the motor case in multiple spots. The best way I have found to get this cover
off is to use a small flat blade screwdriver in a corner. Once you get it started it may
pop off, or you may need to slowly work your way around the cover until it comes free.
Try not bend the cover, and go slow. Now working inside the drive gear assembly,
pry off the small retaining circlip using a small circlip pliers or a pair of small
flat blade screwdrivers. This can be a little tricky to get started. Remove the washer below
the circlip and set aside. Carefully rotate out the gear assembly, making
sure to not damage the O-ring seal as you work it off the shaft. .
Here you can see the wear in the plastic drive gear.
Carefully pry off the old gear. And press on the new gear. Clean away the old grease
in the housing and apply a small amount of clean grease. Reinstall the gear assembly
while rotating it down into position. Install the washer and the circlip. If necessary,
bend the circlp back into normal shape prior to installing. It should audibly click into
place when correctly seated. Now we’ll need to resecure the cover. Here
I have mounted the case in a vise. Be sure to straighten the cover if it was distorted
or twisted during removal. Reinstall the cover being careful to not damage the seal lip.
Tap the cover down until fully seated. Then using a drift, re-peen the cover in a few
spots to hold it securely in place. Reinstall the motor to the case. Notice there
is are 3 locating pins to ensure proper orientation. Install and tighten the 4 mounting screws.
Installation of the servo motor and transfer case crossmember is the reverse of removal
Tighten all fasteners using the proper torques. Tightening torques
Drain / fill plug to transfer case (M18) 33 Nm (24 ft-lb)
Servomotor to transfer case 22 Nm (16 ft-lb) Classification resistor to servomotor 5 Nm
(4 ft-lb) Crossmember to body (vehicle floor) 19 Nm
(14 ft-lb) Crossmember to bushing 68 Nm (50 ft-lb)
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