Transfer Case Actuator potential free fix!

Originally Posted by -jay-

Just finished this earlier today. All the lights on my dash disappeared. It was a pain taking that metal cover off though. Thanks pburnett.

eeekkkk... You shouldn't have had to take off the metal cover... Thats why I tore mine apart, so people could see. There is no need to take the cover off, just turn the gear around.

Originally Posted by angina

ugh, now my ABS and Brake lights are back....

2 things. Are you sure that this is the problem? The 4x4 light should have gone off as well. Also, when you did the gear turn, did you turn it 180 degrees? If you only turned it 90 degrees it is likely that the gear is still in the damaged portion.

Originally Posted by -jay-

.... It was a pain taking that metal cover off though.

I thought pb suggested it is not necessary to take the cover off the actuator in order to rotate the white gear 180 deg.

Unless you really want to clean up the shavings.

I could be wrong as I haven't done this myself.
Mark the position and then use the worm gear or something else to rotate it?

And as I understand it, it isn't necessarily the cure for all instances of the triad of lights.
Just where the clicking sound is heard after shutting the engine down?

Originally Posted by pburnett

eeekkkk... You shouldn't have had to take off the metal cover... Thats why I tore mine apart, so people could see. There is no need to take the cover off, just turn the gear around.

Originally Posted by Supercourse

I thought pb suggested it is not necessary to take the cover off the actuator in order to rotate the white gear 180 deg.

Unless you really want to clean up the shavings.

I could be wrong as I haven't done this myself.
Mark the position and then use the worm gear or something else to rotate it?

And as I understand it, it isn't necessarily the cure for all instances of the triad of lights.
Just where the clicking sound is heard after shutting the engine down?

lol. yea i took it off anyway. i wanted to clean out the shavings and i wanted to be sure that the worn down piece is completely on the opposite side. wasn't too bad. just had to tap it back into place.

so i had my mechanic rotate the gear 180 degrees in the actuator. This resulted in the ABS and Brake light going away, and he confirmed the XDrive was working, but the 4x4 light didn't go away. After driving it around for around 100 miles, the ABS and Brake light came back on. I also started hearing the honking noise after turning the car off. However, I also started getting friction/feedback/shaking on my wheels when turning slowly to the left or right, almost as if something was wrong with the 4x4.. has anyone felt this before?

I felt this a couple months ago (the friction/shaking on wheels when turning) when the 3 lights first showed up, but it went away. Has anyone experienced this?

I am starting to think I just need to replace the actuator with a new one (or that my mechanic didn't fully rotate the gear 180 degrees).

Originally Posted by dgreen78

Anymore updates on how this fix is working? I am having the same issues and will be tackling it this weekend. 06 with 72K on it. Making the clicking on shut off and dash lights on under hard acceleration. Do you need to reset anything in the ECU/TCU after doing this?

Also, if anyone has a used actuator lying around please PM me, I would be interested in making a stronger gear for these (I am a machinist)

I doing same thing

Jay,
How did the top off and when you reassembled the part, was the rubber seal hard to get back on?

so even after I rotated the gear, I was getting the lights inconsistently.... i ordered a brand new actuator and replaced it and now my car is fine. sucks that I had to blow $700 instead of having this workaround actually work.

I've been experiencing the "3 Light" issue along with the "clicking" noise when turning off ignition. Got up under the car this evening to remove the actuator motor and turn the gear to see if it would resolve the problem but ran into access issues. I've got a support bar and a splash guard that runs from just past the transfer case to the rear bumper that is limiting my view and ability to get a socket wrench to the torx bolts. From the sounds of it, some of you have had a pretty easy go at getting to the motor and getting it off. Is my undercarriage cluttered more than yours or am I failing to see the easy route. Any suggestions would be appreciated.

Originally Posted by pburnett

A couple weeks ago, I got the "terrible triad" of lights (ABS, 4x4, and Brake). Recently, I got the clicking noise after turning the car off and was able to determine that it was coming from a transfer case. Using several posts from here, especially this one:

http://www.bimmerfest.com/forums/sho...6&postcount=19

I bought a new transfer case actuator and installed it. Problem solved, no lights, no clicking, all better. It is not a cheap part at 720 bucks from getbmwparts.com, and 900 bucks elsewhere, so the engineer in me wanted to figure out why they were failing.

Which brings me to the purpose of this post. I disected the old actuator to find out what the heck is going on inside it. I appologize for the huge pictures, but some sort of resolution was needed to describe what I was trying to say.

What the actuator looks like when off the car:


And broken down into the pieces: Bottom right is the motor, top right is the brush assembly, top left is a guard of some sort that pops off (albeit bent and unusable once you have it off) and the bottom left is the gear assembly (we'll focus on this one)


After I popped off the oil guard piece, here is what the inside looked like, a ton of shavings and grease.


and closer:



So you can see the motor turns a worm gear which is mated to a black gear (which is made of plastic !!!) Eventually, this gear wears down like crazy and doesnt have any teeth left to grip the worm gear. This is what causes the slipping, and the error lights, and especially the clicking sound.

In this photo, you can see the change from good gear area to the bad area. The good area is on the left, and as you follow the black gear around to the right, you can see where it has been worn down from sitting all the time.




So, I went farther. I took off the black gear to see what it looked like:
Good side (what it should look like everywhere):


Bad side (Cause of the problem)


POTENTIAL SOLUTION:

So now we know what the cause is, how can we fix it? It has been (from my research) that everyone just buys a new actuator. Yes, it fixes the problem, I can vouch for that, but I don't know how many other people looked into what CAUSED the problem.

I bet you could unbolt the motor from the gear housing assembly (it is held on by 4 torx bolts that come off quite easily compared to trying to remove the actuator from the car).
Mark a location of the current position on the white plastic gear you can see in the first photo. After the motor is unbolted and removed (ONLY THE MOTOR, DONT DESTROY YOUR ACTUATOR AND TAKE THE WHOLE THING APART!!!!), turn the white plastic gear 180 degrees from its current location. This takes the bad part of the gear and puts it where it will not get used, which means that a good part is now in contact with the worm gear.

Re-insert the motor and bolt back together. This should give you, say another 65k miles (when mine failed) or so before you likely have to replace the actuator. Re-install on your transfer case, and voila! you should be good to go with only an hour or so of your time wasted instead of time and 900 bucks.

I haven't tried this, so try it at your own risk, but with pulling everything apart, it seems like a pretty safe bet, but obviously I can't be held responsible if something does go wrong.

Hope perhaps it can save someone almost a thousand dollars. I believe my logic is sound, but I look forward to your comments!

Hi there i would like to thank you for the info you posted .today i turned the gear on my x3 like you said and it work like a charm, fantastic thanks

So I did the roation of the gear fix and it worked until this afternoon. I got the three dash lights to go on. After looking around on the web for any new potential news/fixes came across this eBay listing ( item #130632900391). Anyone try this or have any new leads on someone that can make a rebuild kit/gear?

my god.. thats my picture....

Originally Posted by pburnett

my god.. thats my picture....

I didn't even notice, well I figured it was to good to be true and I guess I'll be just replacing the whole actuator this time around.

Originally Posted by pburnett

my god.. thats my picture....

you can get them for copyright infringement and ask for damages $$$$ or at least to lower the price a bunch!

I am in canada, montreal i turned the black gear 180 and its been 4 days now and no problem runs fine in the snow and all around

I turned the black gear 180 and it works fine i am in canada alot of snow here and had no problems

That's great it worked for you, It had worked for a few months for me. I suspect my failure is mostly due to my drivin style. My wife describes it as spirted lol. When I did the rotation I noticed that more then half( closer to 2/3 ) of the black gear had a noticeable "u" grove in it. I fully expected to have to replace the gears(if a kit became available) or the whole actuator.

Originally Posted by yagermj

So I did the roation of the gear fix and it worked until this afternoon. I got the three dash lights to go on. After looking around on the web for any new potential news/fixes came across this eBay listing ( item #130632900391). Anyone try this or have any new leads on someone that can make a rebuild kit/gear?

I bought one some months ago. Perfect on my X5 4.4i.

Hello
if you read this post i was the first to try this solution back on sep 2011 everything was fine until today it last 4 month i took it out and the gear was stripped in the other half
so the question is to buy the whole actuator or just the gear that its posted on ebay ? any advice

Originally Posted by dannyy06

Hello
if you read this post i was the first to try this solution back on sep 2011 everything was fine until today it last 4 month i took it out and the gear was stripped in the other half
so the question is to buy the whole actuator or just the gear that its posted on ebay ? any advice

It's not necessary to buy whole actuator because it comes with same materials. You just need the gear posted on ebay. I can confirm it's a very high quality replacement kit, bronze alloy, indestructible.
It come's with a detailed guide to install kit from yourself.
I'm very satisfied.

Originally Posted by cldchc

It's not necessary to buy whole actuator because it comes with same materials. You just need the gear posted on ebay. I can confirm it's a very high quality replacement kit, bronze alloy, indestructible.
It come's with a detailed guide to install kit from yourself.
I'm very satisfied.

Is there any chance you could scan and post the detailed guide for us to view Also did you take any pictures of the install or replacement bronze alloy gear itself? Thanks for your time.

Guide comes with package.

Thanks

Before folks start using an indestructible metal gear in the transfer case, they may want to go back and review the portion of this thread where some of us pondered the wisdom of this choice over the original plastic gear (Posts #85-87).

A metal replacement gear will be far more durable, without question, than the original plastic gear; but BMW may have deliberately intended that a plastic gear be used in this application in order to protect the more expensive components (e.g., the actuator motor), should the transfer case system become jammed for some reason: the relatively inexpensive plastic gear becomes what's called the "design failure point" and more expensive components (like the actuator motor) are spared failure/burnout.

Of course, this is all well and good -- if one can obtain the failed component (i.e., the plastic gear) without having to purchase the entire transfer case from BMW...

But the fundamental point I'm trying to make is that, by replacing the plastic gear with a metal one, one needs to realize that they run the risk (however slight) of damaging other components in the transfer case or xDrive system should a situation arise where the plastic gear would have ordinarily failed in order to protect those other components...

these components are tested and certified for more than a year.

Originally Posted by cldchc

these components are tested and certified for more than a year.

Which components...? The metal replacement gears...? I have no doubt that they'll last...

That's not the problem I'm talking about, though... The problem I'm describing would arise if mechanisms in the transfer case or xDrive system became jammed for some reason. BMW likely designed that gear to be made out of plastic for a reason other than just to save a few dollars in production costs (although that would have been an additional motivator for them...): it's probably supposed to fail if the system becomes jammed, thereby preventing damage to high-dollar components of the transfer case/xDrive system. A metal replacement gear is not likely to fail under those same circumstances, leading to potential damage to, or failure of, another (probably more expensive) system component -- like the actuator motor.

Now, acknowledging that it's easier said than done in this case, my opinion has become that it's ultimately better to seek out an original plastic gear for this repair, if it becomes necessary (and "pburnett's" 'quick-fix,' outlined at the beginning in this thread, does not do the trick). But folks are certainly free to use the metal replacement gear at their own risk; in most cases, it will probably work out fine for them -- unless they're unfortunate enough to 'win' the lottery where something binds in the transfer case or xDrive system...

Just trying to keep people educated about why some decisions (e.g., the use of a plastic gear inside a transfer case) are made in the world of engineering when on the surface, it seems as if they were made in the world of finance... Carry on...