Transfer case actuator motor gear.
 

Hey I've been noticing that at around the right RPM's my 4x4 ABS light and brake light come on (deactivating all 3). Also when i turn off the engine i hear a clicking noise from under the car. So i did some research, and its become apparent to me that the transfer case actuator gear is worn out. Im usually someone to repair things on my e53 myself (DIY), so i order the gear the seems to be the actual problem so i can replace it this Saturday. While I'm waiting I'm wondering if anyone can tell me how do i take it out from under the car, Or is their a write up or video where someone is detailed about how they take it out from under the car. A lot of videos I've seen they skip that whole part.:dunno:

Go to youtube and look up briansmobile1 he has a video on removing the actuator. There's also a video on replacing the gear on youtube just do a search.

Thanks.

I just did the gear replacement and since there is so much information spread out around the internet and in forums on this topic I created a post to try to consolidate it (see below). So far so good, it fixed the problem no more warning lights and no more clicking when I turn off the car. I chose to replace the gear with a new one rather than risk it failing or slipping back into the worn out portion of the gear, my reasoning being if I was going to spend a Sunday working on this I didn't want to ever have to repeat it :)

I included my photos and the 3 best videos I found on the problem/replacement:

BMW Transfer Case Actuator Problem And Fix

http://24f554c823a5bc6186e5-0abca687...gear-thumb.jpg

This article is an attempt to aggregate information in a single place regarding a defect in the X drive systems of BMWs that will typically affect ALL of the following models of BMWs at one point or another, typically around 80k-120k miles.

2001-2003 BMW X5 3.0 L6 E53
2004-2006 BMW X5 E53
2004-2010 BMW X3 E83

The model year 2001-2003 BMW does not have an actuator gear in the transfer case. See Realoem.com. It uses a different transfer case.

Thanks for catching that, updated. I was basing that off of a part spec that I saw but that must've been in error ...

Just as an FYI. Over 2 years since I have flipped my gear. I have all 4 seasons here, and drive it like I stole it from time to time.

http://www.xoutpost.com/bmw-sav-foru...ixed-sort.html

It is important to mark the position of the gear on the outside, before you take the motor out.

Hi SlickGt1,

Do you replaced just the "gear" with an updated part or you elected to replace the actuator (pn# 27107566296)?

I just flipped the gear 180 degrees. Took me all of 15 min to do, oh and free.

Edit: Given 2 years since you did the alternative "free" solution

How many miles after that?

At least you can tell the story whether "flipping the gear 180 degrees" was short term fix or can even last longer ( wild a** guess equal or greater than 30,000miles)

No, not there yet. 14k miles about. Not one issue so far. That gear, essentially only uses about 30% of its surface. Flipping it over 180 should essentially give it new life. Yea I won't be able to flip it in 70k miles, but right now I am confident it will hold up. Quite a few dirt road experiences and snow, not even a hickup.

Funny, I was just talking with Jeff from Odometer Gears about this issue a few weeks ago (met him at the Vintage show in NC); he sells an improved replacement gear for that. I'm still not sure if my X5 even has that actuator; looking at the drawings in RealOEM, it looks like there were two transfer cases used -- ATC 500, which has the actuator, and NV 125, without. I need to crawl under the thing and have a look; Jeff thought they all had the actuator, but I sure don't remember seeing that wart on the back of the case when I've been under there before.

Odometer Gears - BMW - X5 (E53) 1999-2007

NV 125
http://realoem.com/bmw/diagrams/r/r/534.png

ATC 500
http://realoem.com/bmw/diagrams/r/v/530.png

Amazing testament by SlickGt1. As always thanks for sharing.

Hopefully other owners (with actuator gear issue) will have the same success story to share in this thread! Keep it coming.

To the OP, looking forward hearing from you in the next few days / week(s) or so.

pretty sure this only applies to X drive models. That would be the ATC 500, and you can actually see it in the picture. Right next to the output flange for the rear wheels.

Thanks for the feedback on this. I've seen some posts in which people did the gear flip and said it slipped back into the worn out portion after a time. Hard to tell what they did or did not do wrong.

My gear certainly looked totally unused on one side when i pulled it, it still had the original green lube on the non-worn side:

http://24f554c823a5bc6186e5-0abca687.../gear3-1sm.jpg

The worn side is exactly 180 degrees on the bottom in that photo but you can't tell it's worn in that picture.

I opted to replace the gear all together just to be sure I didn't have to mess with it again for another 60k miles or so ...

So far it's an even 50/50 (with 2 documented incidents in this thread)..
The tie breaker will be the OP :)

But come to think it, SlickGT1 (2yrs and 14,000 miles), the free solution, it will allow the owner to set aside money to buy a genuine BMW new actuator @ approx 750 USD (with two years warranty), and have a back up (old one, replacing the gear) or vice versa repair the gear , then consider a new actuator as the 2nd choice.

I have a feeling that the people that get the issue to come back, simply failed to flip the gear 180.

I was meticulous about that, and before I pulled anything out, I marked up the original location of the gear, against the body. This also made me realize that when you insert the motor back into the actuator body, the gear actually turns quite a significant amount. It took me a few tries to get it to lign up 100% 180 from before I took the motor out.

I also didn't even bother taking off the plate that held the gear inside. That was the other reason to make sure it is well marked up.

When this gear dies, I will replace the gear only. While I had the motor out of the body, I inspected the brushes and the coil, everything looked great.

I absolutely agree that replacing the entire motor (and spending $800 for it) seems really unnecessary. Unless there is something noticeably wrong with the motor housing, brushes, worm gear, etc. the obvious point of failure is the worn gear. Replacing it makes the unit good as new.

The very loud clicking noise that you get just after turning off the car tells you the motor is still good, it's turning the worm gear but not engaging due to the worn out gear teeth on the nylon wheel.

Ebay has some sellers listing the plastic gear for $59 or so:

BMW E53 x5 E83 x3 Transfer Case Motor Gear 27 10 7 566 296gr Heavy Duty | eBay

What is everyone's experience re: brand name?

Amazon has a reasonably priced one also, reviews there are excellent:
BMW E53 X5 E83 X3 Transfer Case Motor Gear 27 10 7 566 296GR Carbon Fiber Reinforced Nylonhttp://ir-na.amazon-adsystem.com/e/i...1&a=B00H2TD5IQ

I got mine from Odometer Gears: www.odometergears.com

The fit was perfect and the part was great quality, though generally twice the price of some of the other options. I can't really compare to the cheaper options as I have not seen or used those (yet).

Guys, an autologic diagnosis of my abs/brake/dsc 'trifecta' pointed to the transfer case. I haven't yet noticed the tell-tale click, but will check for it and am getting a second opinion [hopefully via DIS] on the cause. Assuming the trifecta cause is not an ABS sending unit at a wheel, given all the info on this 'fault,' I'm tempted to replace the gear in the actuator motor and get the ABS module inspected/rebuilt for $99. I view it almost as preventive steps, a reasonable investment at less than $150 for the parts and ABS module service if you DIY. No way I want spend $3k+ to replace the transfer case, the first shop's 'solution.' Any additional thoughts/guidance?

Just sent you PM. If anything the gear in the transfer case needs to be flipped, or replaced. SlickGT1 flipped his and I believe got at least 2 more years of service out of it.

The Bosch 8.0 shouldn't need a rebuild, but it wouldn't hurt. If it were me, I'd swap the gear in the transfer case around (free), see if that makes the trifecta go away. If it remains, then look into the ABS module repair.

If the gear is worn, you should be hearing an audible click 1-2 seconds after shutting the X5 down.

http://johnnyvest.hubpages.com/hub/B...roblem-And-Fix

Slicks reference to flipping the gear below:
http://www.xoutpost.com/bmw-sav-foru...or-gear-2.html

I'll second SlickGT1 repair. More than a year ago, I did mine. I have done about 15,000 kilometers since then, last July alone, we did about 6,500 km. As it was said, the gear gets worn only on about 30% of its circumference, so no need to replace it.

I am still on the flipped gear.

Here's the complete DIY video guide on the replacement:

https://www.youtube.com/watch?v=UR7Vv5SQvDc

I'm still on the flipped gear. Lol. Years now, no isses. Free fix.

I've just done this replacement on my X5. Here are two things I noticed from my experience.

1. If you have the three warnings lights on your dash (ABS, Brake and 4x4) you won't hear the motor gear clicking under your car as it disables the unit until errors are removed. My gear must have been slipping to begin as occasionally all the error lights vanished and I could hear the clicking of the gear again.

2. Prying open the the case to access the gear can be difficult and you need to use WD40 to help pry open the case.

3. Make sure you clear all the old grease/gunk out of the case before installing the new gear. Also, replace the grease with some new product and ensure it is applied to the long gear and the gear you are replacing.

4. If you can feel a slight lag or movement of power from front to rear on acceleration, replacing this gear may solve your issue. Just before it failed I had this issue, after the replacement of the gear the issue was gone. I'm assuming the gear was slipping and the car was unable to engage the clutch inside the transfer case quick enough.

5. I had wear on both the top and bottom side of the gear, I would suggest replacing the whole gear rather than simply flipping it over.

6. The sensor that you remove before you unbolt the motor from the transfer case has a lip and it sits along side the dip in the motor and locks in place as you tighten the nut (I struggled to figure out where it went as I had low light under the car during this procedure).

Hope these tips help.

Wrote a little write up here with photos/ step by step guide for accessing the gear. In my opinion if you're going through the trouble to remove the actuator and get to the gear, may as well replace it. It is cheap enough.

https://bimmerzeit.com/2020/09/04/x3...placement-diy/

Good day folks,

today i removed the actuator motor to replace the gear that's known to wear out. Well, no smoking gun but i will replace it. However I did notice something unusual with the electric motor. I turned it and it has a "stepped" or "notched" rotation. Here's a brief video...
https://www.youtube.com/watch?v=ckFBz4-QF7Q

uncertain if this is a stepper motor. is this normal or is the motor kaput?

thnx for any input.