[rothwem]

I have been having a really annoying shudder on my car since I got it. The symptoms pointed to coils and plugs, however, but when I changed them, it still happened when the car warmed up fully and under 75-100% load around 2700-3500 RPM. I had no CEL. I've got 87,000 miles, but its been doing it since I got the car at 80,000

At my wits end, I took the car to a local shop, where they apparently have seen this a lot in the xi/xDrive cars, and they unplugged the transfer case actuator. Voila, no more shudder. I drove it a bunch last night with the unplugged actuator, let it warm all the way up, did some hard pulls, no shudder. The car actually drives great, pulls harder and smoother than before. I guess I never realized that even when the transfer case wasn't shuddering, it was dragging on the driveline.

I asked them if they would be okay with installing a used unit, and they said they would, but obviously there's no warranty on the part. That's fine with me, but the guy warned me that there is some kind of design flaw in the transfer cases and it would probably happen again with a used unit, and I should go with a new one. If that's true, then why would a new one fix it? Would the brand new transfer case exhibit the same problem? With a $4000 repair, I'd be pretty pissed if it died 80,000 miles later.

So the question is, has the transfer case design been updated for the E9x cars? Mine is a 2009. I didn't see anything in RealOEM that would indicate that the PN has changed, but RealOEM isn't always right.

Also, is it possible to code out the "4x4!" warning message? I'm going to drive around for a bit with the actuator unplugged (RWD, yo! ) and try to figure out a path forward. In the mean time, that pop up is really annoying. I can't see the temp. or time on my dash and it comes back 10 seconds after I clear it.

[AtlasM]

Usually it's the plastic worm gear in the transfer case actuator that goes bad. There's a guy who came up with a metal replacement gear that fixes the problem and supposedly prevents it from coming back.

This is the original youtube video about it:

This is what I found on ebay but I'm not 100% positive it's the original guy with the video. But this seller does have positive feedback on selling this item.

http://www.ebay.com/itm/Bmw-Transfer...-/162519870814

This is the kit with the gear puller tool etc. from the same seller.

http://www.ebay.com/itm/6pc-Kit-Bmw-...m/162519870635

[rothwem]

Hmm, I can't watch the video at work, but I'll save it for this afternoon when I get home.

They said that the transfer case clutches were slipping though. Does a stripped worm gear cause that? I also had no lights.

[AtlasM]

Not sure about the clutches slipping has anything to do with the worm gear. I just know that usually when people talk about problems with the transfer case the source of the issue is the worm gear.

[AtlasM]

Btw if you do need a whole new transfer case and not just the actuator worm gear fix, the best deal I found is on a rebuild for $1775 + $110 core from eEuroparts. I got my rebuilt HPFP from them.

https://www.eeuroparts.com/Parts/182...300-TC00035RI/

[Needbmwpartzz]

I would say if car is old just drive it rwd(also wonder if anyone can code out the x-drive?)

[rothwem]

Originally Posted by AtlasM

Btw if you do need a whole new transfer case and not just the actuator worm gear fix, the best deal I found is on a rebuild for $1775 + $110 core from eEuroparts. I got my rebuilt HPFP from them.

https://www.eeuroparts.com/Parts/182...300-TC00035RI/

That's not bad, but its still a lot of money. I wonder if I could fully convert my car to a real RWD model for $1770.

[rothwem]

Originally Posted by Needbmwpartzz

I would say if car is old just drive it rwd(also wonder if anyone can code out the x-drive?)

Its a 2009, and its actually in pretty great shape. I'm driving it RWD right now, but the 4x4 notification is really really annoying.

[ayyy]

Originally Posted by Needbmwpartzz

I would say if car is old just drive it rwd(also wonder if anyone can code out the x-drive?)

Originally Posted by rothwem

Its a 2009, and its actually in pretty great shape. I'm driving it RWD right now, but the 4x4 notification is really really annoying.

This is probably never gonna happen on the e9Xs with xDrive. See this thread with over 600 posts about people trying to do this. Summary: coding this option is likely not possible without a plethora of warning lights accompanying it. Only way to change an xDrive to RWD as far as I've read is to pull the front driveshaft and code from there

[rothwem]

Originally Posted by ayyy

This is probably never gonna happen on the e9Xs with xDrive. See this thread with over 600 posts about people trying to do this. Summary: coding this option is likely not possible without a plethora of warning lights accompanying it. Only way to change an xDrive to RWD as far as I've read is to pull the front driveshaft and code from there

I'm thinking that there's got to be something to allow an xDrive to think its a RWD. I think the xDrive is controlled by the DSC module, maybe all I need to do is swap in a RWD module and code/flash that to the car.

[rothwem]

So I've just spent a lot of time on RealOEM and various internet sources trying to figure out how to change my xDrive car into a RWD car. Here's a couple notes:

The really tricky stuff:

-DSC pumps and modules are different. I'm fairly confident I could change the module, but I think the most difficult thing is going to be changing the lines, which are different on the RWD models. They probably will also cost a damn fortune. But if I can get the DSC module swapped out, then I can (probably) get the car to realize its RWD.

-The transmission, obviously is different. What makes that tricky is that the transmission is not bolted to the car, rather the transmission is bolted to the transfer case, which is bolted to the car. The transfer case mount looks really different than the RWD transmission mount, and so even if I make this car RWD, I'll probably have to leave the transfer case on there for a while, just disconnected.

The less tricky stuff:
-The following parts are different in front of the transmission
--subframe
--control arms
--strut assemblies, all the way up to tophats
--steering rack
--oil pan
--steering knuckles

Oh, I forgot the trickiest part of this whole deal. I have no garage, no spare car and a gravel driveway. I might be driving around with a bright dash for a while.

[AtlasM]

Fully converting the car over to rwd is a much larger undertaking than replacing the transfer case.

[rothwem]

Originally Posted by AtlasM

Fully converting the car over to rwd is a much larger undertaking than replacing the transfer case.

Who are you, my girlfriend?

Seriously though, I never wanted AWD anyways, its just that manual/RWD wagons are super rare and cost a lot. I think I might be able to source a lot of parts from car-part.com, and maybe even do it for less than the cost of the transfer case.

At least that's the goal. We'll see if it happens.

[floydarogers]

FYI, there's a thread on F30post about converting a F31 to RWD. They went full-bore and replaced the tranny with a RWD tranny so it was pricey.

http://f30.bimmerpost.com/forums/sho....php?t=1164655

[rothwem]

Originally Posted by floydarogers

FYI, there's a thread on F30post about converting a F31 to RWD. They went full-bore and replaced the tranny with a RWD tranny so it was pricey.

http://f30.bimmerpost.com/forums/sho....php?t=1164655

Nice, I just read through that thread. One thing that they had going for them on the F30 is that the dsc modules and brake lines for the xDrive and RWD cars are the same. I'm really dreading running the brake lines on this car, and it might be the thing that causes me to abandon this project. I need to find a thread or something where they do that.

[rothwem]

Originally Posted by rothwem

Nice, I just read through that thread. One thing that they had going for them on the F30 is that the dsc modules and brake lines for the xDrive and RWD cars are the same. I'm really dreading running the brake lines on this car, and it might be the thing that causes me to abandon this project. I need to find a thread or something where they do that.

Oof, so I made a Bill of Materials for the DSC and Brake lines. Just brake lines are going to cost ~$500, and that doesn't even address the blood loss from my hands as I try to thread them through the car.

My retrofit doesn't seem so encouraging at the moment.

[table][tr][td]Part name[/td][td]xDrive[/td][td]RWD[/td][td]Cost of RWD[/td][/tr]
[tr][td]pipe (rear)[/td][td]34326764049[/td][td]34326762823[/td][td]22.95[/td][/tr]
[tr][td]pipe (rear)[/td][td]34326853542[/td][td]34326762834[/td][td]23.23[/td][/tr]
[tr][td]Pipeline with pressure hose[/td][td]34326853543[/td][td]34326853504[/td][td]37.69[/td][/tr]
[tr][td]Pipeline with pressure hose[/td][td]34326853544[/td][td]34326853503[/td][td]37.69[/td][/tr]
[tr][td]Pipe (front)[/td][td]34326853535[/td][td]34326853500[/td][td]35.95[/td][/tr]
[tr][td]Pipe (front)[/td][td]34326853537[/td][td]34326853501[/td][td]47.6[/td][/tr]
[tr][td]Brake Hose Front[/td][td]34306793026[/td][td]34306790550[/td][td]38.2[/td][/tr]
[tr][td]Holder, Brake Hose Left[/td][td]34306771691[/td][td]34306770483[/td][td]30.24[/td][/tr]
[tr][td]Holder, Brake Hose Right[/td][td]34306771692[/td][td]34306770484[/td][td]30.24[/td][/tr]
[tr][td]DSC/DXC pulse generator front[/td][td]34526764858[/td][td]34526870075[/td][td]104.95[/td][/tr]
[tr][td]DSC/DXC pulse generator rear[/td][td]34526764859[/td][td]34526870077[/td][td]108.95[/td][/tr]
[tr][td][/td][td][/td][td][/td][td]517.69[/td][/tr][/table]

EDIT: I guess this forum doesn't support tables

[AtlasM]

Originally Posted by rothwem

Who are you, my girlfriend?

Seriously though, I never wanted AWD anyways, its just that manual/RWD wagons are super rare and cost a lot. I think I might be able to source a lot of parts from car-part.com, and maybe even do it for less than the cost of the transfer case.

At least that's the goal. We'll see if it happens.

Haha I'm just looking at it from the perspective of how much it'll cost to make the transfer case problem go away, either by A) repairing/replacing the transfer case or B) converting to rwd. I just don't think there's a way to do option B for cheaper than A.

That transfer case link I posted is a great deal. It's an OEM-branded version of the part vs. BMW branded but it's otherwise the same thing (think like the TRW branded M3 control arms instead of BMW) and still warrantied.

Something else to keep in mind with this conversion idea is the front suspension and steering rack are totally different between rwd & awd. Maybe you could keep them when converting over to rwd, maybe not?

[rothwem]

Originally Posted by AtlasM

Haha I'm just looking at it from the perspective of how much it'll cost to make the transfer case problem go away, either by A) repairing/replacing the transfer case or B) converting to rwd. I just don't think there's a way to do option B for cheaper than A.

That transfer case link I posted is a great deal. It's an OEM-branded version of the part vs. BMW branded but it's otherwise the same thing (think like the TRW branded M3 control arms instead of BMW) and still warrantied.

Something else to keep in mind with this conversion idea is the front suspension and steering rack are totally different between rwd & awd. Maybe you could keep them when converting over to rwd, maybe not?

Yea, that rebuilt transfer case is still a possibility. I'm looking into just trying to code out the transfer case from the dsc though, and that should be free/cheap to do.

From there, I realize that the front suspension/subframe/steering rack is different on the RWD cars, its substantially better actually. Quicker steering ratio, subframe and control arms are aluminum, m3 parts drop right in, and the front suspension has almost 2" more suspension travel. I would LOVE to swap all that stuff.

I also think I could get a little money for the front diff, CV axles, driveshaft, oil pan and subframe since they're in good shape.

[rothwem]

So, I decided to try changing the transfer case fluid, just to see if that would fix any shuddering. I've heard of it working in limited slip differentials that are chattery from worn clutches. I figured, the fluid is $45 for a liter, which is expensive, but its cheaper than a transfer case, and it just might work.

And whaddya know, I plugged the actuator in, reset the adaptations ("calibrate the VGSG") with INPA and the shuddering stopped. I haven't put many miles on it, but I'm driving it to the mountains this weekend and I'll see if the transfer case starts acting up again.

Its kind of a bummer being AWD again, the car definitely felt faster with the transfer case unplugged.

[Moorea]

Hey - newbie here...
2008 BMW 335xi

We had the ABS/4x4 warnings as well as a light crunch upon starting the car. We took it in for a diagnostic at our shop, and he said that they aren't able to determine if just the motor needs to be replaced ($1,000) or the entire transfer case ($3,700). If we replace the motor and it doesn't work, we still have to pay that $1,000 plus the $3,700 for the new transfer case. That sounded like a crappy position to be in so I called our shop we used from back when we were in Chicago and he validated that advice. The Chicago shop also said that he usually replaces the motor first and there has only been one case where the entire transfer case needed to be replaced. The SF shop on the other hand, said since the entire motor is metal (whereas most other transfer cases have plastic parts) we probably need to replace the whole transfer case. Sounds like a mean lottery game to me.

Any advice as to which path we should pursue? I've done exhaustive research (tried the left to right cranking, unplugging and replugging the battery cables), and now my head is spinning. I'm leaning toward replacing the motor first, but I don't really know.

Any advice is appreciated!

------
Error Codes
5462 VTG: Fault, servomotor or coupling force too high
5463 VTG: Mechanism faulty
55C3 VTG: AWD limp-home control activated. No DSC specified nominal torque
5F3A DSC: Transfer case: internal
------

[hassmaschine]

Originally Posted by rothwem

So, I decided to try changing the transfer case fluid, just to see if that would fix any shuddering. I've heard of it working in limited slip differentials that are chattery from worn clutches. I figured, the fluid is $45 for a liter, which is expensive, but its cheaper than a transfer case, and it just might work.

And whaddya know, I plugged the actuator in, reset the adaptations ("calibrate the VGSG") with INPA and the shuddering stopped. I haven't put many miles on it, but I'm driving it to the mountains this weekend and I'll see if the transfer case starts acting up again.

Its kind of a bummer being AWD again, the car definitely felt faster with the transfer case unplugged.

old thread but I clicked on it and the first thing I thought of was did you change the fluid?

It needs to be done every 90k or so; the fluid has friction modifiers for the clutches which wears out over time. The friction modifiers allow the clutch disks to "slip" a certain amount, once that's gone the clutches lock too tightly and cause it to bind.

[rothwem]

Originally Posted by hassmaschine

old thread but I clicked on it and the first thing I thought of was did you change the fluid?

It needs to be done every 90k or so; the fluid has friction modifiers for the clutches which wears out over time. The friction modifiers allow the clutch disks to "slip" a certain amount, once that's gone the clutches lock too tightly and cause it to bind.

Yep, I'm really glad I didn't go for the new transfer case right away.

I've put about 1000 miles on the car since I did the transfer case fluid and its still driving well. I might swap the fluid out again at 100000 miles (car has 90,700 on it right now) just to see if I can get more crap out of the transfer case, the old fluid was pretty nasty.