[skier_du]

My transfer case worm gear just took a dive a couple nights ago. I've been researching them to see what's current for solutions. While I was perusing ebay for a less expensive actuator motor replacement, I came across someone selling a replacement worm gear they made of their own design. It looks like it could be legit. The guy is out of Newark NJ and makes these himself out of mild steel. He appears to be a CNC machinist. Anyone try this or have any idea as to how well this may work? If this does actually work out, other than labor, this is finally a cost effective, @ $60, fix for our transfer cases!

http://www.ebay.com/itm/111520586910...S:1123&vxp=mtr


Thoughts? Comments?

[u's2drift]

I emailed the maker of this. Nice guy. Made this because the worm gear in his 328xi was damaged and didn't want to have to buy the whole unit.
Thoughts.... If you are driving your XI car normal IE not launching nor power shifting, I think this unit is great and will work for anyone. If your track or street racing then I can see it being an issue. The gear that the worm spins is plastic if I'm not mistaken. Either way the maker feels that it won't hold. He can make that gear out of a harder metal, just he hasn't had to. Also he hasn't sold any. I believe it could be worth a shot of trying only if your current worm gear needs to be replaced, you are willing to do the work yourself and if the gear breaks you are understand you'd have to replace the whole unit. It hasn't been proven and there is only one 328xi out there (the makers) doing the r&d.

[ajsalida]

Great find! This was talked about several years ago, did not realize someone actually went out and did it.

[skier_du]

Originally Posted by u's2drift

I emailed the maker of this. Nice guy. Made this because the worm gear in his 328xi was damaged and didn't want to have to buy the whole unit.
Thoughts.... If you are driving your XI car normal IE not launching nor power shifting, I think this unit is great and will work for anyone. If your track or street racing then I can see it being an issue. The gear that the worm spins is plastic if I'm not mistaken. Either way the maker feels that it won't hold. He can make that gear out of a harder metal, just he hasn't had to. Also he hasn't sold any. I believe it could be worth a shot of trying only if your current worm gear needs to be replaced, you are willing to do the work yourself and if the gear breaks you are understand you'd have to replace the whole unit. It hasn't been proven and there is only one 328xi out there (the makers) doing the r&d.

Thanks. Good to know.
Thoughts... I feel that if one is racing the XI, it doesn't matter if it's this gear or the factory, it will eventually go out. that having been said: I'd be reluctant to make the gear much stronger. Once it's strong enough, then the week link is shifted. Which of course means the likelihood of breaking something more expensive to repair would be higher. I don't know about you, but I'd rather replace the worm gear than break any part of the actual transfer case.

Originally Posted by ajsalida

Great find! This was talked about several years ago, did not realize someone actually went out and did it.

Agree. It's about time an engineer/machinist picks this up.

[JaysBlueE92]

i remember reading about this a while ago..

[skier_du]

The guy who makes it, Jerry, is going to try to make a video of how to install the worm gear into the actuator.

[skier_du]

Here's the how to video.

[u2b]https://www.youtube.com/watch?v=CsmQ3VrDgxQ[/u2b]

[JC335xi]

Here you go

[JC335xi]

Originally Posted by skier_du

Here's the how to video.

[u2b]https://www.youtube.com/watch?v=CsmQ3VrDgxQ[/u2b]

FYI just put the part after the "=" between the tags.

[InCityPhoto]

Can you do this without removing the actuator from the car? As in remove those two screws while its still on the TC.

[skier_du]

Originally Posted by InCityPhoto

Can you do this without removing the actuator from the car? As in remove those two screws while its still on the TC.

You could try. But the space in there is very tight. I'm not sure you'd have enough room to work. Taking out the brace that goes across with the t-case bushing frees some room. But even then it's only 3 more bolts to get the entire actuator off and a lot less headache.

[Joe NYCALIVE]

Anyone looking to buy a transfer case motor? I have that I bought and put it on only to find out that my entire transfer case needs to be changed. Smh. So its brand new just a little dirty from installing it and removing it. Let me know. Brand new its 700+ I only want 600 for it.

[terryd5150]

I can see the point of not wanting a stronger material than stock for the worm gear; you'd want the worm gear to wear down and break, not the transfer case itself.

With that said, does BMW offer the worm gear as a replacement part or do you have to buy the whole actuator motor?

I've only checked ECS and they only offer the entire actuator.

[wgknestrick]

No. You want nothing to break. The best thing is to keep replacing and stressing things until nothing breaks. If we only need to throw $500 at the transfer case to make it robust, then that is money well spent.

Right now we need people testing these out to see what the limit is. I already bought one in case I need it. Transfer cases are not wear items

[mikes4]

The worm gear is available from eBay or you can get the actuator from ecs. I bought the worm gear thinking that was what was causing my issue and when I uninstalled/disassembled it the worm gear was fine. Put it back together and ordered an actuator. That didn't fix it either. The transfer case later grenaded itself (internal pump failure) and I replaced the whole thing. If anyone needs either a replacement worm gear (unused) or actuator (used for 10 miles!) I have them both for sale.

My car was stock 110k miles

[mikes4]

And to clear up some other stuff there are no plastic gears in the transfer case actuator. The worm gear is metal and the gears it interacts with are metal as well. The internal workings are lubricated with grease and if you do replace that worm gear because it is indeed stripped you will need to clean that old lube + metal particles out and then re lube it. Clean it with a a couple cans of carb or brake cleaner and some towels or cotton swabs. And then lube it with something that will last like a tube of Amsoil grease or Mobil

If you are doing the worm gear replacement you will need a gear puller to get the thing off the shaft once you cut slots into it. I bought a gear puller that's used on RC motors and then modified that to be able to fit around a slotted worm gear. It's a little involved but not impossible.

Other tip. When pulling off the transfer case mount you will encounter the long bolt that goes through the mount and you will have to drop the exhaust off the hangers to get it out. Put that thing in the other way when you reassemble. Make your life easier.

Service your transfer case wile you are there. Ecs sells a service kit. You will need a fluid pump to get it done. Harbor freight sells one for 6 bucks it works great.


Transfer case fluid smells horrible.

If anyone needs any help with this stuff PM me. I took that joker off like 5 times while troubleshooting

[stashtrey]

I did this a couple months ago. Worked perfectly. Problem immediately solved.

If you don't have a gear puller the seller on eBay sold me one for $20...and he is a great guy as noted above.

I didn't have to pull any exhaust hangers. It took some man handling but I for it in and out without too much trouble.

Good luck ...you can do it!

[dannyboy451]

I purchased this worm gear and installed it myself using the procedure posted here:http://www.e90post.com/forums/showthread.php?t=633200. I actually spent more time trying to pull the old worm gear off the actuator motor than I spent removing and re-installing the motor itself. I built my own gear puller very similar to the one above out of some 1.5"x3.5"x.120 rectangular steel tubing and was initially unsuccessful (didn't have a hardened bolt/nut for pushing so the threads stripped). It was getting late so I sprayed some penetrating oil on it and let it sit overnight. I tried it again first thing in the morning (again with an unhardened M6 bolt and nut) and it popped right out. Just needed a little oil, I guess. In hindsight, it would definitely be worthwhile to just buy his puller considering the time I spent screwing around improvising my own. Had I done that, I could easily have done this in a day instead of stretching it into two days. Total time breakdown was:

2 hrs to jack up the car, gather tools, and remove the unit
6 hrs trying to pull the old gear off (would have been 30 mins had I bought the seller's puller)
1 hr cleaning out the old grease, re-greasing the new gears, and chasing down a new O-ring after one stretched out from the carb cleaner I was using
1.5 hrs putting everything back together

Since I plan on keeping this car for quite a while, I ordered a spare from the seller just so I'd have one on hand if I ever need to do it again. As I understand it, sudden power transfers are the main cause of worm gear failure. Living in MN, I'm constantly driving on ice-pavement transitions, so it would make sense that mine went out at about 80,000 miles.

A complete description of the issue I was having can be found here:http://www.e90post.com/forums/showth...=388537&page=3, post #56.

Thanks to all for sharing this knowledge. Saved me HUGE money!

[dannyboy451]

Originally Posted by mikes4

Other tip. When pulling off the transfer case mount you will encounter the long bolt that goes through the mount and you will have to drop the exhaust off the hangers to get it out. Put that thing in the other way when you reassemble. Make your life easier.

+1 on that tip.

Also, my actuator gear did not perfectly mesh with the transfer case gear on installation. Be advised that the gear that this meshes with inside the transfer case only rotates one direction (UP as you look inside) and spring returns DOWN. You will not be able to turn the actuator assembly gear once the new worm gear is installed. As such, I had to insert, then slightly rotate the actuator assembly (counter-clockwise as viewed from the rear of the car) upon re-installation to get the bolt holes to line up. Try and turn it the other way, and you may break something. I tried rotating the wheels to get it to line up better, but no dice.

[Z3SpdDmn]

Originally Posted by JC335xi

Here you go

Does anyone have a good picture of what the OTHER gear is supposed to look like? The one that he shows at 5:30 in the video? I pulled mine apart last night and that gear's teeth are concave. If they're supposed to be straight, then THIS is the gear that I need. Not the worm gear. My worm gear looks fine. All the teeth are sharp and the same size.

Does anyone have a junk actuator motor that they'd send me this other gear from (the one shown at 5:30 in the video)?

Thanks!

[psmitty95]

Any of you that tried this have updates? My transfercase is finally going out and i’d ideally rather not just swap in a new one that is bound to fail at my power level again. Already have a new one ordered but would like to upgrade it before swapping. Not sure whats wrong with it as the car still drives totally fine just have a clanking noise at low speeds and the oil was metallic

[Julian2485]

Originally Posted by psmitty95

Any of you that tried this have updates? My transfercase is finally going out and i’d ideally rather not just swap in a new one that is bound to fail at my power level again. Already have a new one ordered but would like to upgrade it before swapping. Not sure whats wrong with it as the car still drives totally fine just have a clanking noise at low speeds and the oil was metallic

Too much power on that xi of your bro. What oil has metal in the transfer case fluid ?