Transfer case noise after changing fluid.

[scotty339]

EDIT - Video uploaded. Driving back and forth in my garage a few times. You can hear what I believe is the t-case chain ratting untill it comes to a rest.

https://linksharing.samsungcloud.com...kUrlVersion=V0
Alternate Video Link -

https://vimeo.com/464610908

Looking for some insight.

Did an engine oil change as well as the front / rear diffs and the transfer case this morning and now I seem to be getting some t-case noise.

Some things to get out of the way first;
- Vehicle was level and all fill volumes were done to the lower lip of the fill plug.
- DTF1 was used in the T-Case (as required for the ATC45L) and 75W-90 was used in the F/R Differentials.

Windows up the noise is not heard inside the cabin.
Windows down the noise is heard inside the cabin during hard acceleration but predominately when driving past a parked car, bridge, wall whatever, the ticking sound is heard much easier from under the vehicle.
At say 40MPH, going into neutral, the sound will go away. Only can reproduce the sound while in Drive and there is a load on the drivetrain.
Driving in tight circles/figure eights no clunking or knocking is heard from the front end or rear end leading me to rule out the differentials.
I have no engine hesitation or transmission shifting issues or any thing else obvious.

I know on the E70 there was a requirement for the clutch packs to be re-calibrated via ISTA, however, I did some reading and it was my understanding that it was NOT required for the F15. However, I suppose you can't believe everything you read on the internet.

This excerpt from newTIS leads me to believe otherwise.

Link - https://www.newtis.info/tisv2/a/en/f...box/1VncIb2Awl

Home / BMW F15 X5 xDrive35i SAV / Repair Manuals and Technical Data / 27 Transfer box /
AM2701_00133 - Transfer box, noise

Brief description of the test module for non-electrical diagnosis:

Transfer box (VTG), noise

Applies to:

E70, E71, F15, F16, F25, F26, F85, F86

with all-wheel drive

Content (excerpt):

Howling from around the transfer box when driving at speeds between 50 km/h and 120 km/h
Pulsating noise from around the transfer box while accelerating or cornering
Scraping noise from around the transfer box
Banging noise from around the transfer box

Vehicle communication: No
ISTA path:
Activities / Information search / NED / 01 Drivetrain / 01 Noise / Transfer box noise
Important note:

The fault patterns in the test module depend to some extent on the production period, optional equipment, motorisation and other features. It is therefore possible that not all content or different content to that described above may be displayed for different vehicles.

I do not have an e NET cable or ISTA but I'll be ordering one tonight and seeing what I can do when it comes.

In the mean time, whats everyones risk assessment for driving less than 100 miles untill I can get it re-calibrated?

Anyone else experienced this?

Thanks!

[ProjektAutoScott]

We always run the ISTA procedure any time the fluid is touched, or the case is acting up. Do that ASAP, I don't know of any transfer case procedure where that is not recommended, but I can't guarantee that will change anything that sounds like "ticking" as all that procedure does is adjust where, and how much force is applied to the clutch pack that sends power to the front wheels. Plus the 35i generally doesn't create enough torque to cause these issues like the 50i models do. It's also not super likely swapping fluids would create a tick, but you never know.

Did you do anything with the crossmember, heat shields, ground straps or anything else that might be loose or making contact with the driveline/underside of the car? is the sound periodic, and follows wheel-speed? Are you positive the sound wasn't there before? How much fluid did you pull out vs fill? Did anything external make it's way into the fill hole, like a rock, or a fluid tip?

You can also unplug the transfer case servo connector, it's right there in the way of the drain plug. Driving with it unplugged disengages the clutch pack permanently, and you can see if anything changes. This is also the safest scenario if you need to drive on it for now. You will have dash lights for braking, 4x4, DSC, but the car will be fine and RWD only plus, it will save the clutch pack and servo from any damage.

You should post the sound if you can capture it, maybe strap a gopro or a mic to the case, or the bottom of the car. Best of luck to you, hopefully it's something easy

[scotty339]

Originally Posted by ProjektAutoScott

We always run the ISTA procedure any time the fluid is touched, or the case is acting up. Do that ASAP, I don't know of any transfer case procedure where that is not recommended, but I can't guarantee that will change anything that sounds like "ticking" as all that procedure does is adjust where, and how much force is applied to the clutch pack that sends power to the front wheels. Plus the 35i generally doesn't create enough torque to cause these issues like the 50i models do. It's also not super likely swapping fluids would create a tick, but you never know.

Did you do anything with the crossmember, heat shields, ground straps or anything else that might be loose or making contact with the driveline/underside of the car? No. I have the angled 14mm german oil drain tool which allowed me the clerance to get in without removing anything. All that I removed was the re-enforcing plate under the engine for access to the front differential.is the sound periodic, and follows wheel-speed? The sound does not seem to get louder or quieter which I am next to a wall to hear it. It is the same weather it is at highway speed or low speed.Are you positive the sound wasn't there before? Yes, I drove around most of the summer windows down and have never head this sound beforeHow much fluid did you pull out vs fill? The levels of fill as mentioned were all up the upper edge of the lower lip of the fill plug, as per newTIS. I did find some conflicing values on the fill volume of the ATC45L case, some being 1.25 for a drain fill, 1.45L for a new install and another source said 0.7L for a drain and fill. I got about .7L in which is roughly what I took out. Did anything external make it's way into the fill hole, like a rock, or a fluid tip?I cant see anything that made its way in that should of. The only thing I can think of is that the fluid suction gun may of moved or hit something? I used a U shaped and 90degree angled piece of brake line as an adapter on the end to get to the bottom of the casting, but I did not jam it in or damage anything to my knowledge.

You can also unplug the transfer case servo connector, it's right there in the way of the drain plug. Driving with it unplugged disengages the clutch pack permanently, and you can see if anything changes. This is also the safest scenario if you need to drive on it for now. You will have dash lights for braking, 4x4, DSC, but the car will be fine and RWD only plus, it will save the clutch pack and servo from any damage. I'll leave it parked for the night. I've done enough for the day says the wife. I'll unplug the connector tomorrow morning and take it for a drive and see if the sound has any changes or is still present.

You should post the sound if you can capture it, maybe strap a gopro or a mic to the case, or the bottom of the car. Best of luck to you, hopefully it's something easyAs mentioned, video is in the first post. It really sounds like a chain slapping inside or something to me.

Video with sound posted. Link in 1st post.
EDIT - Added comments above in bold.

Thank you very much for the detailed response.

[smyles]

IIRC the TC reset just resets the fluid life counter. It's not the same adaptations like in ZF transmissions (and even those preferably should be left alone).

If the sound is indeed coming from inside the TC, I suspect a piece of brake line or some other foreign object got into it.

[scotty339]

Originally Posted by smyles

IIRC the TC reset just resets the fluid life counter. It's not the same adaptations like in ZF transmissions (and even those preferably should be left alone).

If the sound is indeed coming from inside the TC, I suspect a piece of brake line or some other foreign object got into it.

Anything is possible I suppose. I made a specific piece solely to avoid that issue this morning.

[turboawd]

In your video I only hear some sort of fluttering sound, but it occurs even when you're not moving. So that would rule out and driveline issue.
You'd have more noise when turning if you had a t case issue.

[ProjektAutoScott]

Originally Posted by smyles

IIRC the TC reset just resets the fluid life counter. It's not the same adaptations like in ZF transmissions (and even those preferably should be left alone).

This is 100% false, do not spread that as good info to anyone. The specific transfer case reset procedure in ISTA adjusts how the servo engages the clutch pack based on feedback from the servo itself. When correctly carried out, you will hear the TC testing itself and you will get a confirmation screen showing exactly what adjustment value was made, or if the adjustment was a failure. The car is not capable of doing so automatically. It has nothing to do with a "fluid life counter", thanks.

(I have no comment about the ZF transmissions, other than to say that's also not true at all, careful what you read out there)

Edit: Just barely did one this week, here is a photo of the calibration screen on a recently serviced case

[turboawd]

Originally Posted by ProjektAutoScott

This is 100% false, do not spread that as good info to anyone. The specific transfer case reset procedure in ISTA adjusts how the servo engages the clutch pack based on feedback from the servo itself. When correctly carried out, you will hear the TC testing itself and you will get a confirmation screen showing exactly what adjustment value was made, or if the adjustment was a failure. The car is not capable of doing so automatically. It has nothing to do with a "fluid life counter", thanks.

(I have no comment about the ZF transmissions, other than to say that's also not true at all, careful what you read out there)

But I'd argue that a transfer case reset is not necessary just because you changed the fluid. I never had any issues and never did the reset.

[ProjektAutoScott]

Originally Posted by scotty339

Video with sound posted. Link in 1st post.
EDIT - Added comments above in bold.

Thank you very much for the detailed response.

Sorry for all of the dumb questions, have to start somewhere lol!

It's hard to know if that sound is coming from the TC. The sound I am hearing Also seems to be present when the car is not moving, but in gear. The transfer case is directly tied to the driveshaft and axles, and no parts are moving when the vehicle is stopped.

When I say is it periodic, I mean to ask if it follows the speed of the car when you are driving- does the ticking speed up when the car is speeding up, and slow down when the car slows down? or does it seem to follow engine RPM, rather than wheel-speed?

Almost sounds like wastegate rattle tbh

Again, best of luck to you and sorry to hear about it. Noises like that also drive me nuts! I'm sure you'll figure it out

[ProjektAutoScott]

Originally Posted by turboawd

But I'd argue that a transfer case reset is not necessary just because you changed the fluid. I never had any issues and never did the reset.

We are trying to avoid the anecdotes here, like yourself. The change in viscosity and clutch/metal particulate matter in the worn fluid can be relevant to the performance of the transfer case. This is why all TC procedures recommend the adaptation reset, this is it's sole purpose. If you are having issues with your TC, this is the first step we, the dealership, and most indy shops will take.

I am glad it worked out for you, your case is probably just fine, but again it's not recommended.

[smyles]

BMW themselves say reset isn't necessary after fluid change in atc45. But hey, what do they know, right? (insert lifetime rant here)

[scotty339]

Originally Posted by turboawd

In your video I only hear some sort of fluttering sound, but it occurs even when you're not moving. So that would rule out and driveline issue.
You'd have more noise when turning if you had a t case issue.

I feel like some of that was the echo in the garage. That being said, I can only reproduce the sound when the vehicle is in Drive. Driving down the road and putting the vehicle in neutral I can not reproduce the sound.

[Gkacmaz]

Hey your issue sounds pretty similar to mine (check out my post in the "howling noise") I thought it was my Transfer case but it's my front differential that went bad. The noise only came under load and couldn't be reproduced when it put the car into neutral while driving there's even a video I put up in that thread

So I have the same noise and went to my mechanic to get it checked in my case it comes from the front differential. Brought the car to the dealer since I have extended warranty so we'll see how it turns out

Here's a Video of my issue

https://drive.google.com/file/d/1wwg...w?usp=drivesdk

[scotty339]

Originally Posted by ProjektAutoScott

Sorry for all of the dumb questions, have to start somewhere lol! No problem. Always need a baseline when diagnosing to ensure the baseline things are covered.

It's hard to know if that sound is coming from the TC. The sound I am hearing Also seems to be present when the car is not moving, but in gear. The transfer case is directly tied to the driveshaft and axles, and no parts are moving when the vehicle is stopped. When driving down the road in D, when revving up the throttle I can reproduce the sound. When driving down the road, shifting into neutral and listening, be it idle or revving in N while still rolling down the road, I can not get the sound to happen again. This leads me to rule out exhaust rattle, waste gate ratte ect,

When I say is it periodic, I mean to ask if it follows the speed of the car when you are driving- does the ticking speed up when the car is speeding up, and slow down when the car slows down? or does it seem to follow engine RPM, rather than wheel-speed? It seems to follow the load on the engine more so the wheel speed. As mentioned, when driving in a situation that would create the sound, driving by that same spot in Neutral coasting through, when the engine is idle or revving to say 2K, the sound is NOT present. I can only recreate it when there is a load on the drive train.

Almost sounds like wastegate rattle tbh

Again, best of luck to you and sorry to hear about it. Noises like that also drive me nuts! I'm sure you'll figure it out

EDIT - Update. After I posted the 5 minute drive video below I pulled the T-Case Actuator Plug. Sound is STILL PRESENT. Albeit maybe less present and slightly quieter, that could be in my head. Well then....

Some creative usage of zip ties and I got my phone positioned right next to the t-case.

5 minute test drive video. I aplogize, I don't think you can skip in the video with this Samsung video hosting.
https://linksharing.samsungcloud.com...kUrlVersion=V0

In this video, at the 3:40 minute mark, you'll hear the car go into neutral as I rev it three times to try and re-create the sound. At numerous points, such as 1:30 backing out of my drive way, accelerating at 2:15, 2:47 through to 3:00 during accelerations. 3:30 as well. 3:40 again is when I shift into neutral. 3:55ish I shift back into drive and the sound starts occurring again. This video should shed way more light on my problem. 4:40 is a pretty good capture of the sound. Video ends at 4:50 pulling into my garage.

Watching this video, there seems to be a constantly present rattling occuring.



Two other videos -
https://linksharing.samsungcloud.com...kUrlVersion=V0
You can hear it when revving up and getting ready to move, just before the car pulls and the load goes to the drive train, the sound happens.

This video driving by vehicles you can hear it when going by a car and the sound is bounced back up.
https://linksharing.samsungcloud.com...kUrlVersion=V0
Hard to get a good sound with the wind noise. I'll pull the T-Case actuator and see if I still get the sound when driving.

[turboawd]

Kinda hard to tell. You check to make sure no heat shield or anything is close to touching the driveshafts?

[scotty339]

Originally Posted by turboawd

Kinda hard to tell. You check to make sure no heat shield or anything is close to touching the driveshafts?

Going to jack the car back up. Pull the front re-enforcing plate over the engine/front diff and check my work aswell as all the way to the back again. I don't see when something could of bent but I'll double check to rule that out.

EDIT - Pulled the re-enforcing plate off. Checked all the front CV axles, rotate fine, no contact. The rear shaft off the T case to the rear axle, the heat shield was slightly close, but not touching. I've bent it further downwards to increase clearance.

That being said.... I did notice some play in my intermediate "front" drive shaft. Where it connects and comes off the t-case and heads back to the front wheels, still getting some play. While the t-case is disconnected, the front wheels are still turning the cv axles which in turn is turning the intermedite shaft. Could this be the cause of the noise? This would bode well with the theory as to why the sound was noticeably quieter when I did the test drive with the t-case disconnected. The front wheels are still turning the shaft and making it move, but with the t-case not throwing it any power, it has much less torque and rotational force on it so the sound could be less noticeable?

Just confused if this is it why would it happen now? Bad timing? Seems odd that after doing F/R Diffs and T-Case that the sound would start then.

Video - https://linksharing.samsungcloud.com...kUrlVersion=V0

Originally Posted by Gkacmaz

Hey your issue sounds pretty similar to mine (check out my post in the "howling noise") I thought it was my Transfer case but it's my front differential that went bad. The noise only came under load and couldn't be reproduced when it put the car into neutral while driving there's even a video I put up in that thread

So I have the same noise and went to my mechanic to get it checked in my case it comes from the front differential. Brought the car to the dealer since I have extended warranty so we'll see how it turns out

Here's a Video of my issue

https://drive.google.com/file/d/1wwg...w?usp=drivesdk

See above. Not nearly as much play as you have, but defiantly some play.

[ProjektAutoScott]

Originally Posted by smyles

BMW themselves say reset isn't necessary after fluid change in atc45. But hey, what do they know, right? (insert lifetime rant here)

You know when they do say it's necessary?

When you have a concern about proper function of the TC, especially after any service work. The function is there for a reason on the F15, here is a list of what that calibration is responsible for:

" Demand for required locking torque (comes from the DSC control unit)
Condition of the transmission oil (calculated in the VTG control unit)
Multidisc clutch wear (calculated in the VTG control unit)
Load on transfer-case servomotor (calculated in the VTG control unit)
Transmission oil temperature (calculated in the VTG control unit) "

[turboawd]

How much play does your front prop shaft have? There was a recall a while ago on the previous generation x5. a few years ago I noticed play in mine f15. And I changed it for a new one since it didn't cost too much. The new one still had play! It's just the way it is I guess.

[ProjektAutoScott]

Originally Posted by scotty339

That being said.... I did notice some play in my intermediate "front" drive shaft. Where it connects and comes off the t-case and heads back to the front wheels, still getting some play. While the t-case is disconnected, the front wheels are still turning the cv axles which in turn is turning the intermedite shaft. Could this be the cause of the noise? This would bode well with the theory as to why the sound was noticeably quieter when I did the test drive with the t-case disconnected. The front wheels are still turning the shaft and making it move, but with the t-case not throwing it any power, it has much less torque and rotational force on it so the sound could be less noticeable?

Just confused if this is it why would it happen now? Bad timing? Seems odd that after doing F/R Diffs and T-Case that the sound would start then.

Not to eliminate the possibility completely, but play from the TC coupling to the front drive-shaft is pretty normal, and not likely to be the cause of a tick.

It's very unlikely it's just bad luck. When a problem arises right after you do work, it's probably related in some way. Sounds like you may want to spend a little more time pinpointing the area you are hearing it from, maybe with the help of someone else. As I mentioned earlier, I like to strap a gopro, or a mic to the component I think is causing the issue. The sound will be unmistakable if you get it right

[smyles]

Yeah, and a simple fluid change won't affect the pressure values simply because there isn't enough difference in properties b/w new and, say, a 60k miles one (aside from darker color, that some 'servicemen' use to scare customers and to 'told ya!').

If TC malfunctions, then yes, adaptation may change values significantly; however, it's like changing wet clothes on a guys with a fever: you make him feel better, but don't address the underlying causes - clutch pack or chain wear, stuck actuator, etc. etc.

And since ZF was mentioned, this is why so many customers feel happy after tranny fluid changes - reset adaptations make clutches slightly slip until the proper values are built back up, but to them it's rediscoved smoothness and therefore feel good about $$$ well spent....

[ProjektAutoScott]

Originally Posted by smyles

Yeah, and a simple fluid change won't affect the pressure values simply because there isn't enough difference in properties b/w new and, say, a 60k miles one (aside from darker color, that some 'servicemen' use to scare customers and to 'told ya!').

Interesting story... There is plenty of difference in 60,000 miles on the synthetic oil in these cases. Just like a tranny, that friction material is suspended in the fluid, and the viscosity degrades enough to have an effect on all sorts of drivetrain components including transmissions and TCs, this is proven. By the same logic, you are agreeing with a lifetime interval, which I know you don't, as you mentioned earlier. Regardless, not the point here.

For OPs sake: if you have a concern with the TC, the adaptation reset is one of the first, and easiest steps to do. There is no good reason not to do it.

I'm not sure what your goal is here, but you just said it yourself:

Originally Posted by smyles

If TC malfunctions, then yes, adaptation may change values significantly; however, it's like changing wet clothes on a guys with a fever: you make him feel better, but don't address the underlying causes - clutch pack or chain wear, stuck actuator, etc. etc

Sounds like a great way to eliminate a few potential concerns via a 15 second software procedure, right? For all we know, he is having a slight engagement issue now as a result of the fresh, particulate free fluid in his TC.

You also have a sprung clutch pack with an actuator that isn't set up to adjust itself over time as clutch material wears. Notice how in my post above there was a 6.9* rotational adjustment to the servo on a TC that was "just fine" with 62,000 miles on it when it was serviced.

Clutch pack wear is manageable in the case, and should be compensated for. A stuck actuator would be quickly identified as a failure by ISTA.

The adjustment is super easy, and recommended. There is your rant

[scotty339]

ProjektAutoScott, thank you very much for the detailed follow up. I enjoyed reading your ATC45L rebuild for your 50i. Very informative.
smyles, turboawd, Gkacmaz, thank you all for your input and followup.


I'll be bringing the vehicle into the dealers as I am under my extended warranty. I'll see what happens. Have some other issues to get looked at. Classic F15 HUD randomly not working. Drivers side above seat controls Dakota Leather cracking. Squeak from the front left wheel. Recreated when driving with local dealer shop foreman. And the door linkage on the front passenger seems to have a disconnected as the pop up indicator no longer moves and seems to be stuck inside the door.

I'll be sure to report back on how it goes and what happens.