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BMW X3 transfer case problem

707K views 860 replies 249 participants last post by  Glenpointe 
#1 ·
Hi guys,

Just joined up. As a newbie on Bimmerfest i wanted to know how many members have actually had or heard of transfer case problems with these X3's. Mine is a 3 litre petrol auto. BMW says they dont generally cause problems but im not so sure on that now as the car has only done 33000kms since new and has never seen any real hard work. So i'm thinking there must be an inherent problem in these.

Any help or ideas?

Mine started developing a whinning noise a few thousand K's back.
 
#713 ·
Transfert Case Error Code and 4x4 light up

Hello,

my car is an X3 e83 03/2006, I already change the actuator gear on it. But i still have the 4x4 light up all the time when i start the car.
Sometime the ABS and Brake light come up also.

I have download the VM from Rheingold with all the BMX software in it (INPA, ISTA+, NCSExpert,....), buy a K+DCAN- OBDII cable on amazon, modify it to be use on the older X3.

When i run the ISTA+, the following codes:
52D2 VTG: Lead, servomotor (signal name: IMP)
54C6 VTG: Oil Wear
5F3A DSC: Transfer case: Malfunction

Base on these error codes, do you have any idea what could be the problem?
- Actuator Resistor
- Yaw sensor
- left ABS/speed sensor

Thanks so much
Didier
 
#714 ·
Hello,

my car is an X3 e83 03/2006, I already change the actuator gear on it. But i still have the 4x4 light up all the time when i start the car.
Sometime the ABS and Brake light come up also.

I have download the VM from Rheingold with all the BMX software in it (INPA, ISTA+, NCSExpert,....), buy a K+DCAN- OBDII cable on amazon, modify it to be use on the older X3.

When i run the ISTA+, the following codes:
52D2 VTG: Lead, servomotor (signal name: IMP)
54C6 VTG: Oil Wear
5F3A DSC: Transfer case: Malfunction

Base on these error codes, do you have any idea what could be the problem?
- Actuator Resistor
- Yaw sensor
- left ABS/speed sensor

Thanks so much
Didier
Make sure you reset Transfer case calibration after you change fluid, check wire going to it for shorts or connected all the way. Look at wheel speed sensors while driving to find if there are any glitchy/acting up sensors.
 
#715 ·
more clues for transfer case condition

>any trash in the oil when you changed it

>any slop in the front drive shaft when you rotate it at the transfer case output.....this will show a sloppy chain/drive/bad internals

>you can get the angle of rotation of the drive into the clutch pack from ISTA .....if it goes high it usually shows the internals are shot

>follow the experience in this link and see how you can check the rotation manually .....do all the other checks and report back

>worst case is replacing the guts of the transfer case ....a very doable diy .....best wishes

http://www.bimmerfest.com/forums/showthread.php?t=932385&page=3
 
#718 ·
Hello Guys,

So I have perform the Transfer Case Oil Change, not found any trash in it.
Perform the calibration with ISTA ==> Success

Change the resistor of the Actuator. ==> no special improvement

Clean all fault with ISTA ==> Success.

After driving a mile, again 4x4 light up.
ISTA show the following


52D2 and 5F3A

Do you have any advice what to do next?
Do you have a procedure to get the angle of rotation of the drive into the clutch pack from ISTA?

Thanks so much fro your help.
Didier
 
#722 · (Edited)
had chance to do this ????

>follow the experience in this link and see how you can check the rotation manually .....if it spins freely round and round past 90 degrees or so it is maybe kaput....do all the other checks and report back...the same as DFM415 and others

post 57 shows bad rotation ....then post 67 shows good rotation after rebuilt transfer case was installed

there is also a routine in ISTA and DIS57 that tests the angle of rotation

http://www.bimmerfest.com/forums/showthread.php?t=932385&page=3
 
#723 ·
r3cent experience with pulling out the TC and rebuilding

I have recently pulled out and rebuilt the ATC400 TC from my E83 2007 3.0Si with N52 engine. Been driving two years with a broken transfer case, but I don't recommend doing this as all the electronics that control the car are basically off, so you get the raw uncontrolled power on two rear wheels, with no ABS or ATS, etc. It is no good in the rain and snow, deep water and you are most likely to lose the control of the car in an extreme situation.

To get your car repaired, my advice would be - first test all the sensors - yaw, rotation, etc. with INPA first to be sure that they are OK, change the transfer case oil and see if it makes any difference (probably waste of $$ but maybe worth a try), change the actuator, reset/calibrate the actuator (VERY IMPORTANT, use DIS for that), if all that does not work, just pull the TC out of the car. It is not an easy job, but definitely doable. You will need a lot of tools, I bought also a compressor, impact wrench (500ftlb), sets of extensions, four ramps to put the car on them, and a good jack to place the car on the ramps.
The E83 diagnostic codes give you little guidance - problem with diagnosing the TC fault codes is that they have to be interpreted in sets and timing, a combination of codes in different order can mean something different.

So, I have pictures and filmed most of the process of rebuilding the TC and will post an exhaustive post here when I have some free time to do that, but to answer your questions/concerns in the light of what I have learned:
- the transfer case has multiple points of failure - it can be the chain, the bearings, clutch plates or thrust bearings.
- the shaft where the actuator goes can be rotated, if it rotates too freely, your thrust bearings are shot, at least one of them (this was my case). I think you even can pass the calibration, but what it does not create enough pressure on the friction plates and the front wheels do not engage. I don't think that without previous experience you can tell if the shaft rotates 'good' or 'bad' using your hand only. Now, the common case with the ATC400 is that the thrust washer is worn out and 'explodes" - a good illustration of the issue can be found here http://cobratransmission.blogspot.com/2017/03/atc400-atc500-thrust-bearings.html

- If you pull the TC and decide to regenerate your itself, get all the sets from Cobra transmissions, those will pretty much cover all the potential issues with the TC:
* the bearings kit https://cobratransmission.com/bmw-x3-bearing-kit-55133001-1?zenid=3290fb2145aae593a4df07c99738d106

* the seal kit: https://cobratransmission.com/bmw-x3-seal-kit-55133003-1
* two thrust bearings https://cobratransmission.com/BMW-X3-X5-Thrust-Bearing
* a chain https://cobratransmission.com/bmw-x3-chain-55133005-1

all around $400 and change all at once. you can get a remanufactured/used transfer case, but you never know what is inside of it. All the ATC internal parts are the same, no matter what the year of your ATC400 TC box is.

- this is how the TC looks inside https://jpat.co.uk/uploads/1/0/3/5/103549764/2018bmwatc400.pdf
- Get the OEM TC fluid, or the RAVENOL, which is the OEM that BMW uses https://www.amazon.com/dp/B00QCVP6UK?tag=vs-auto-convert-amazon-20

- pulling out the box itself is a little tricky, not too much guidance on the internet on how to do that on the E83, so a few tips - you will be able to do this having the car only on ramps, the TC box is heavy but not too heavy for one person. I was able to get it out and put it back myself, no other help required. you will need to remove the exhausts, so order two exhaust gaskets beforehand, and four exhaust bolts. get a can of antiseize and stripped nut toolset, in case the rusted bolts cant be removed with standard tools. you will also need to unscrew the giubo (flex disk) and the nuts are self locking, so get three of those (on the internet, as the dealer charges 3x so order ahead. you will need lots of antiseize and a bottle jack to support the transmission. Harbor Freight is your friend. you will need a set of good quality star sockets to do all the work on the TC itself + torque wrenches.

- you NEED to calibrate the TC after the job is done, if you don't the car will be 'grinding' at low speed or have 4x4 engaged permanently or exhibit some other behavior that you don't want. Use the DIS software for that, look for it on eBay

A few good links:

- http://www.bimmerfest.com/forums/showthread.php?t=932385&page=3

- http://www.bimmerfest.com/forums/showthread.php?p=9942871#post9942871

- http://www.bimmerfest.com/forums/showthread.php?t=846517

- https://www.youtube.com/watch?v=mPIgNH7TiYs

>follow the experience in this link and see how you can check the rotation manually .....if it spins freely round and round past 90 degrees or so it is maybe kaput....do all the other checks and report back...the same as DFM415 and others

post 57 shows bad rotation ....then post 67 shows good rotation after rebuilt transfer case was installed

there is also a routine in ISTA and DIS57 that tests the angle of rotation

http://www.bimmerfest.com/forums/showthread.php?t=932385&page=3
 
#724 ·
Ninja250, I just read your post on the TC, very good. I replaced chain, bearings but didn't replace thrust bearings. To be honest, I didn't even look at that. When I take the actuator motor off, I can spin the shaft back and forth really easy. Now I have to take everything off again and start over. You live and learn. Thank you for the post.

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#726 ·
No good, but at least you have found the problem. I would not find the thrust bearings issue if I haven't found a lot of loose metal stuff mixed with the transfer case oil. Those were the chunks of the bearing. I searched what could have gone wrong and found out that the bearing was missing entirely from the clutch pack.

Now that you have some practice, pulling out the box for the second tie will be much easier.

Unfortunately I need to pull the TC again as well, I installed only one new thrust bearing, not two. When the car is warmed up, from time to time I still get the 'triad' and the TC does not calibrate correctly any more. Probably the second thrust bearing also disintegrated under load - I have to pull it out and inspect.

Live and learn!
 
#725 · (Edited)
good results from rlltide12 using friction modifier in the transfer case

>see rlltide12 write up on his transfer case saga and the success with friction modifier

>post one etc below

http://www.bimmerfest.com/forums/showthread.php?p=11791185#post11791185

rlltide12 rlltide12 is online now
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Location: Alabama

Join Date: Dec 2017
Posts: 5
Mein Auto: 2007 X3 3.0si M-Sport
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07 E83 M-Sport Surging Under Acceleration
I recently had an experience with my 07 X3 that I thought I would share in hopes it might help someone.

I bought the vehicle about a year ago, 90K miles on the clock, 3.0 N52/GA6L45R/ATC400, and ever since that time, I have experienced a surge/jerk/miss/wheel slip feeling when under acceleration. The engine seemed to be running perfect.The only code the vehicle was throwing was a VANOS solenoid sticking error.

I began by changing both the VANOS solenoids. No change.

After reading some here, I used DIS57 to clear adaptations per Yomama and swampx3s forum fully expecting that to resolve the issue. No joy.

Next, the engine still had 6 Bosch coil packs. I talked to the dealership, and a TSB exists stating the Bosch coil packs were prone to failure due to heat. Suggested replacing with Delco. Purchased 6 new coil packs and plugs. Installed, and of course, no change.

I had also read of many with upstream o2 sensors causing this type of issue. Unplugged both of mine to put it in limp mode, still surging.

I began thinking that something transmission/torque converter could possibly be causing the issue. It felt like a slipping tire or clutch almost. So on that premise, I changed transmission fluid and filter, and added a shudder stop addative. Again, no change.

Checked all driveshafts/guibo. All good and tight.

Then my thoughts shifted to the transfer case. I knew that some have an issue with the gears in the actuator stripping, but under most all circumstances, the trio of lights would be on. I had no lights, but knowing this is a common issue, I figured what the heck, I'll change them as preventative maintenance.

To test, I pulled the plug off the actuator and test drove. Bingo! The surge was gone! Ordered the gears and a litre of TF-0870 oil. Put the car up on the lift, removed the actuator, disassembled it, and the black gear had about 6 teeth with damage. Replaced the gears, added new oil, reassembled, used ISTA to perform oil change test plan and cleared VGT adaptations, and took it for a test drive.

The surge was almost gone, but it was still there. S*&@! Talked to another member here (thanks swampx3) and decided to try some LSD Friction Modifier, typically used in limited slip rear ends, in the tcase. My thought was that LSDs use clutch packs bathed in gear oil, and this addative helps the clutches do their job. I drained off some fluid and put 3oz in. Took it for another test drive and it is smooth as glass!

It took me almost a year to track this issue down, mostly because 2 hours separated me from my car lift and it was tough to get up and work on it. I had not found this solution here yet, but others may have used this solution in the past. This solution is not on any repair plans from BMW, so try it at your on risk. I don't know how long it will solve my issue, but for now it is prolonging what I figure is a worn clutch pack in my tcase. Feel free to chime in and add your experience!
 
#727 ·
2005 BMW x3, 3.0

Hey Ya'll...am new in this discussion and am trying to find my way around. My X3 (built 14 miles from my home in South Carolina) has served faithfully for years but recently had a used transfer case installed by a BMW repair shop. I am now plagued with the three lights we all seem to be familiar with. I replaced the actuator motor myself and just got done. The lights are still on and it will not do 4x4. There is no "clicking" from underneath. I have tried the lock to lock with the steering wheel and am about to go nuts. This is now my spare car so I do not need it but I want it to be working...what if it snows here in SC???
The battery is getting weak as the car turns over rather grudgingly but it does start. The used TC had 120k miles and it has operated smoothly with no noise or vibrations. Anyone have any suggestions other than arson?
 
#729 ·
Hey Ya'll...am new in this discussion and am trying to find my way around. My X3 (built 14 miles from my home in South Carolina) has served faithfully for years but recently had a used transfer case installed by a BMW repair shop. I am now plagued with the three lights we all seem to be familiar with. I replaced the actuator motor myself and just got done. The lights are still on and it will not do 4x4. There is no "clicking" from underneath. I have tried the lock to lock with the steering wheel and am about to go nuts. This is now my spare car so I do not need it but I want it to be working...what if it snows here in SC???

The battery is getting weak as the car turns over rather grudgingly but it does start. The used TC had 120k miles and it has operated smoothly with no noise or vibrations. Anyone have any suggestions other than arson?
I got my three lights issue resolved with a new actuator gear and transfer case oil change. Also a re-flashing (adaptive) of the transmission computer. Working great now!

Sent from my iPhone X using Bimmerfest mobile app
 
#728 ·
Done various reset procedures?

Checked the TC's fluid level, and was filled with the correct fluid?

Electrical connector tight?

It was a new actuator (and gear)?

After clearing the ODB-II codes, which one reappear? (Using a BMW-specific scanner)

If an original battery, it is time. However if good, then you too need a trickle-charger until the power drain(s) is/are found and fixed.
 
#733 ·
Very Weird transfer case issue, Help!!!

I bought a 2004 X3 3.0 Automatic as a flip. When I bought it the 4X, ABS and brake light where on. It coded indicating bad Servo actuator so I purchased a rebuilt unit and installed. Code and lights went away and everything looks good until you drive it. After about 5 minutes I start to get a bad rear end noise which leads me to believe the rear differential is going out and when you accelerate there is a shaking and even weirder when you brake it feels like both rear brake rotors are seriously warped. and a few times when making left hand turns you can hear a clicking sound coming from left front side indicating a bad CV axle. However, Disconnect power for the new actuator and all the mechanical problems disappear and X3 drives normal with no issues. Of course the dash indicators of transfer case issues are lit once again. Anyone have any idea what's going on?
 
#735 ·
I bought a 2004 X3 3.0 Automatic as a flip. When I bought it the 4X, ABS and brake light where on. It coded indicating bad Servo actuator so I purchased a rebuilt unit and installed. Code and lights went away and everything looks good until you drive it. After about 5 minutes I start to get a bad rear end noise which leads me to believe the rear differential is going out and when you accelerate there is a shaking and even weirder when you brake it feels like both rear brake rotors are seriously warped. and a few times when making left hand turns you can hear a clicking sound coming from left front side indicating a bad CV axle. However, Disconnect power for the new actuator and all the mechanical problems disappear and X3 drives normal with no issues. Of course the dash indicators of transfer case issues are lit once again. Anyone have any idea what's going on?
Are all your tires the same brand? If yes do they all have even wear? If yes is the air pressure set correctly in each? If any of the above are not a yes at times the actuator will try to compensate for these issues. Been there done that with a nail in my tire for a week or 2 and not low enough on air to trigger the sensors, but it sure did screw with the actuator which kept kicking into 4 wheel drive every time I turned.
 
#734 · (Edited)
Kenza and DFM experience

>good work on pulling the power and isolating the issue to the transfer case ...BUT ...gotta dig deeper

>follow the experience of Kenza and DFM ....check codes for the T case internals ....pop out t case actuator and do what DFM did....best wishes

http://www.bimmerfest.com/forums/showthread.php?p=11611121&posted=1#post11611121

KENZA's path to transfer case happy times
a good outcome for KENZA with the $995 swap transfer case....maybe give Steven a call

http://www.bimmerfest.com/forums/sho...=982402&page=2

kenza kenza is offline
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Hi everyone!

Just to finish up this thread: I got a refurbished transfer case from http://www.tcbmwx5.com/. A+++ service, highly recommended. Steven is great to deal with.

Anyway, as soon as I put the transfer case, lights went away. My car is 100% operative now. Although I replaced the chain inside the old transfer case, it seems that the clutch pack was also shot.
 
#736 ·
fixed

Tire sizes are the same but brands are different with matching pairs front and rear. I changed the transfer case fluid and like magic all the problems went away. As bad as the front and rear behaved I never would have thought something as simple as a fluid change in the transfer case would have fixed all my issues. With that said I also recommend anyone else who goes thru something similar that you would use the recommended fluid as its a lot more like an ATF fluid than it is gear oil.
 
#739 ·
Hello to all,
I've had the triad for sometime. Talked to a few people about getting the dis software to read codes etc. I didn't get the software due to computer issues. I bought a Foxwell NT510 pro scanner. I also found a website that mentioned an active test on components. Well I done the active test on the transfer case actuator motor and I could hear it cycling through. I done this twice because I was sitting in the car the first time. Not for sure what I was hearing. The 2nd time I was down on the ground under the car listening. After the 2nd time, I decided to start the car hoping that the Triad would go off. To my surprise the triad went off and has been off since yesterday. Drove the car a total of an hour to and from work. No issues. Keeping my fingers crossed.

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#740 · (Edited)
Hi all

I have opened a thread on this but thought I would post here my symptoms for further opinion

BMW X3 2006 148k miles.

Current light on ABS, 4x4, brake light, puncture light. So total 4 lights. Car jerks and hesitates. When turning in 1st gear, the car sometimes stops, and you have to take it out of gear and put it back in gear again to move off. This is only when turning in first/low revs, the car also clunks and jerks during this manoeuvre.

Lights fist came on about 6 weeks ago, then went off. I took it to my local garage with the lights off, car running fine. They plugged it in and gave off 4 codes, non relating to transfer case. Only one of importance seemed to be ABS sensor (speedo is not working on the car at the moment!). I have it booked in for a replacement speed sensor next week at indi garage. Now, when I picked my car up from the garage, the lights were on and stayed on...weird that the lights have only come back on since it was plugged into computer.

I have only had the car for 6 months. Budget tyres were on when I bought it, I replaced 2 rears as they were shot. Again budget tyres, difference brands but same size/tread as the front. The lights did not come on when I put these new tyres on a few weeks back.
 
#741 ·
X3 Transfer Case Compatibility

Hey All,

Brand new to posting here, though I've read through a ton of posts for X5(previous car) and the X3. I have the transfer case issue - 4 light, etc... and have determined that it is indeed a bad transferase. Question is - will a 2004 ATC400 TC fit a 2007 X3? Not sure after reading everything I can online - some places I look the TC seems to be the same for 2004-2010 - but in other places there seem to be 2004-2006 and 2007-2010 designations. Any help would be greatly appreciated.

Thanks!
 
#742 · (Edited)
>put the last seven of your VIN into realoem.com and get your exact transfer case part number....then.....do the same for any other part your are thinking of substituting

below is an example of a very early E83 ....best wishes

you can also call Cobra Transmission or Stevens' outfit that does the rebuilds in Los Angeles....check the post from Kenza and DFM415

RealOEM.com - Online BMW Parts Catalog

http://www.realoem.com/bmw/enUS/showparts?id=PA93-USA-05-2004-E83-BMW-X3_30i&diagId=27_0018
 
#744 ·
This is a partial repost from my original post elsewhere. Some of the information may not be needed but this thread appeared more promising than my original thread for my current issue(s)...

Update: I have since replaced both motor mounts. That was pretty easy, I think 45 minutes or so from start to finish. This past week I installed a factory used oem axle. It did have a little play on the outside cv joint. Checked everything in the front end and double checked. I did indeed buy an axle 1 inch short. Now that I have the newly used axle in and new motor mounts I have a pretty terrible vibrating especially when slowing down. I've ordered carrier bearing and flex disc to compensate for possible vibration in that area. I've also noticed that i can hear the newly used half shaft rotating at low speeds with window open and quite surroundings. Wondering if possibly I purchased a not so ideal used axle? The clunking in the rear end while turning at low speeds has gotten a lot worse and now whines. Unplugging fuse number 26, related to xdrive actuator, stops the clunk and whine under low speed turning conditions.

After the vehicle has sat for 6 weeks or so and I'm finally back on the road I've also noticed a 4x4 light staying on similar to if you depress DSC button. I've read about possible water damage to xdrive module? Battery issues or even alternator going out? Without throwing more money that I don't have at this lemon of a car, does anyone have any suggestions on order of operations regarding diagnostics? I'm avoiding a new xfer case purchase if at all possible but I'm leaving towards that being the problem. I don't have a dedicated scanner to check specific BMW codes for things like interior mechanism failures.

I suppose jacking up the vehicle and putting it in drive would indicate fwd or rwd. What would cause the vehicle to stay in fwd vs staying in rwd when for example the actuator doesn't engage clutch pack for front drive line. Also i would like to mention my one tire is a few psi low as I just checked them. I cannot fill the tire and need a new Schrader valve. Could 3 psi on one tire trip wheel speed sensor causing dsc to activate?

Sorry for the long post kind of blotched together a few issues. At my whits end with this car.

Sent from my SM-N950U using Bimmerfest mobile app
 
#747 ·
good science for check the transfer case chain etc

>post 2 from WASD

http://www.bimmerfest.com/forums/showthread.php?p=12384870#post12384870

SexieWASD SexieWASD is offline
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When you change the oil take ahold of the front drive shaft and turn it by hand. You will be able to feel how loose the transfer case chain is. Your looking for less than 1 degree or so of play. I recently changed my tc servo gear and fluid. Iput my borescope inside the case to see how loose my chain is. I have around 3 degrees of play and can see the chain isn't fully engaged on the gears, so it's still working, but quite badly stretched, and could cause total tc failure soon, so i'm replacing the chain this weekend, I found one for $88. I'll do a quick write up on it as well as upload the video from my borescope and pictures, but it's super easy to check as you don't have to take anything apart.
 
#748 ·
My Transfer Case Saga - Unifecta, not Trifecta

Mine is a 2008 X3 auto with 79,000 miles with its life spent in NJ and NY primarily non-garaged. I had the light trifecta that was eliminated six months ago with replacement of one real axle and its speed sensor. (Maybe could have accomplished the same thing with emery cloth and the speed sensor.)

Now I have the 4x4 yellow light alone. The truck seems to drive fine EXCEPT when starting to move from a stop with steering wheel turned fully or almost fully left or right (e.g., parallel parking) when there is bucking when I start to move. Dealer recommended transfer case replacement (this without the preliminary step of determining if the servomotor or its plastic gear is bad). Tech noted code indicating "coupling force too high". There is absolutely no clicking or other noise from the transfer case. The BMW X-drive/DSC explanation (attached) says that 4 wheel drive should be completely deactivated at the times when I am experiencing the bucking.

I am speculating that the bucking is caused by there being some torque still being applied to the front wheels when it should be completely "off". This might be consistent with the "coupling force too high" fault code, i.e., if the servo motor is not putting the cam that controls the transfer case clutch in the fully "off" position, torque could still be going to the front axles. I am also assuming that if the servomotor is not operating or if the plastic gear is stripped, the cam in the transfer case will naturally return to the zero front wheel torque position at the bottom of the cam. But what would cause the servomotor to be activated when the electronics are designed to be in the completely off position?

So far I'm stumped. Any thoughts would be appreciated.
 

Attachments

#749 ·
Mine is a 2008 X3 auto with 79,000 miles with its life spent in NJ and NY primarily non-garaged. I had the light trifecta that was eliminated six months ago with replacement of one real axle and its speed sensor. (Maybe could have accomplished the same thing with emery cloth and the speed sensor.)

Now I have the 4x4 yellow light alone. The truck seems to drive fine EXCEPT when starting to move from a stop with steering wheel turned fully or almost fully left or right (e.g., parallel parking) when there is bucking when I start to move. Dealer recommended transfer case replacement (this without the preliminary step of determining if the servomotor or its plastic gear is bad). Tech noted code indicating "coupling force too high". There is absolutely no clicking or other noise from the transfer case. The BMW X-drive/DSC explanation (attached) says that 4 wheel drive should be completely deactivated at the times when I am experiencing the bucking.

I am speculating that the bucking is caused by there being some torque still being applied to the front wheels when it should be completely "off". This might be consistent with the "coupling force too high" fault code, i.e., if the servo motor is not putting the cam that controls the transfer case clutch in the fully "off" position, torque could still be going to the front axles. I am also assuming that if the servomotor is not operating or if the plastic gear is stripped, the cam in the transfer case will naturally return to the zero front wheel torque position at the bottom of the cam. But what would cause the servomotor to be activated when the electronics are designed to be in the completely off position?

So far I'm stumped. Any thoughts would be appreciated.
Now that you mention the cam not being in the correct position, when I replaced the plastic gear in my actuator motor i didn't reset anything. Also that is when my clunking began at low speed corners.

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