[CoolATIGuy]

Hi all!

2016 340i F30 X-drive, 6MT, M Sport, ~142,000 miles


- Pure 800 cast turbo (not the older core-charge version)
- SPEC Stage 3+ Clutch for single mass flywheel
- SPEC single mass Steel Flywheel
- BMS intake
- ctlss downpipe
- B58TU HPFP
- ProTuningFreaks Flex Fuel Kit
- All 6 NGK Spark Plugs replaced last summer
- All 6 ignition coils replaced last summer
- All 6 Bosch injectors replaced last summer
- Valve Cover replaced last summer with new OEM
- Lowered on H&R springs
- Michelin Pilot Sport All Season 4 tires on all 4 corners
- Slotted StopTech Brake Rotors on all 4 corners
- MHD with David Shoup custom tune


It is becoming more often over the last couple of months, where under either heavy acceleration (especially a shorter pull in one gear and then sudden let off), or after a sustained higher speed, it will start shuddering (somewhat at cruise, but mainly under any acceleration). You can see the gear shift stick shake back and forth, and feel it in the body and steering wheel (even through the electric steering), especially at lower rpm and heavier throttle.

Sometimes it will throw codes as well (although not always) - sometimes Chassis Stabilization Malfunction (it's done this a few times, both in a corner taken quick and hard as well as multiple times while under heavy straight line acceleration, sometimes it gives 1BC11F "Gear sensor, communication: Faulty" DME active code, sometimes 213A2D "Dual-mass flywheel, component protection: damaging operating point" DMD shadow (inactive) code (even though I have a SMFW and high-HP clutch).

Turning the car off and back on clears the Chassis Stabilization Malfunction, but usually letting the car sit for a few minutes or overnight helps the shudder go away. If you drive it gentle, it usually won't return. On a 700 mile roadtrip a couple months ago, it started about an hour or so into the trip and persisted the entire way, and kept acting up for around a week or two following. I took it in to have looked at, but then it stopped acting up while they had it in the shop, and then on my drive home after picking it up, it returned.

Any thoughts?

[toxik]

does clutching in make the shudder stop or does it have no effect?

[CoolATIGuy]

Originally Posted by toxik

does clutching in make the shudder stop or does it have no effect?

Does not seem to make much difference with clutch in or out, although the shudder is mainly evident under throttle; it’s not as noticeable when cruising/decelerating..

[toxik]

Originally Posted by CoolATIGuy

Does not seem to make much difference with clutch in or out, although the shudder is mainly evident under throttle; it’s not as noticeable when cruising/decelerating..

you had all the mounts inspected? guibo, trans to transfer case mount, driveshaft center support bearing, and engine mounts?

when was the last time you did your drievtrain fluids? im not sure if a fluid change would get rid of shudder but if theres a lot of miles on those fluids, it may be a clue into something wearing prematurely.

[CoolATIGuy]

Originally Posted by toxik

you had all the mounts inspected? guibo, trans to transfer case mount, driveshaft center support bearing, and engine mounts?

when was the last time you did your drievtrain fluids? im not sure if a fluid change would get rid of shudder but if theres a lot of miles on those fluids, it may be a clue into something wearing prematurely.

When I took it into the shop, they said my engine mounts had quite a bit of play (especially passenger side), and also some play in the trans mount (not a ton, but x-drive so have to take stuff down anyways to get to the motor mounts so might as well save on the labor). But, while they had it the issue went away (until right after I picked it up, of course). It’s not bad all the time though - it will be fine, then you might do a hard pull, then immediately start shuddering under acceleration (usually without throwing any warnings). But if you let it sit, it will go away.

[toxik]

Originally Posted by CoolATIGuy

When I took it into the shop, they said my engine mounts had quite a bit of play (especially passenger side), and also some play in the trans mount (not a ton, but x-drive so have to take stuff down anyways to get to the motor mounts so might as well save on the labor). But, while they had it the issue went away (until right after I picked it up, of course). It’s not bad all the time though - it will be fine, then you might do a hard pull, then immediately start shuddering under acceleration (usually without throwing any warnings). But if you let it sit, it will go away.

the car sitting and problem going away part, is what lead me to ask about the state of mounts, since heat cycle would affect those rubber parts, in fact i remember reading about someone having a very similar vibration/judder issue with a BMW guibo (not f30) only when the car was at operating temps and not when cold.

[CoolATIGuy]

Originally Posted by toxik

the car sitting and problem going away part, is what lead me to ask about the state of mounts, since heat cycle would affect those rubber parts, in fact i remember reading about someone having a very similar vibration/judder issue with a BMW guibo (not f30) only when the car was at operating temps and not when cold.

It's a good point, the main weird thing though is that it won't do it, then you do a pull, then it seems to come on fairly suddenly and persists. As opposed to gradually getting worse

Maybe it is the guibo though

[CoolATIGuy]

Now the symptoms are getting worse, and more frequent. Tonight, it felt like the whole car was shaking much more aggressively, and I could hear it as well, like something was loose/rattling underneath. All day the chassis stabilization warning constantly kept coming up too; I could turn the car off and back on at a stoplight and clear it, but within a mile it would pop right back on again, not even under heavy acceleration or shifting or high speeds, just very light steady throttle on surface streets in a straight line.

When the chassis stabilization warning would be on, it also today started having issues with rev matching. For example, if I would be decelerating in 4th gear, and shift down to 3rd (6MT), instead of holding at say 3-4k rpms for a few seconds like normal, it would drop straight down to more like 2k rpms, hold there for only like half a second, then drop to idle. Not every time though, it was intermittent.

It shakes the least when cruising at steady throttle, a little more when decelerating, the most by far when accelerating. It is better at mid-rpms like 4k, at 2-3k rpms it is worse.

I've had a 1BC11F - Gear sensor, communication: Faulty DME active code on and off for a couple months as well.

I'm wondering if it is a guibo? Or maybe a driveshaft bearing?

Thoughts?

[CoolATIGuy]

My BMW shop disconnected the driveshaft and rear wheels from the equation, did a test drive, issue persisted, so it's something in the front looks like. They said they don't hear anything coming from the front diff, so they think it's a front axle. They checked and said front passenger side is tight, but front drivers side has some movement and clicks. Here is a video: https://streamable.com/yns4q8

Based on all the symptoms in this thread, this new info, and the video clip, would you concur with their theory? Needs a drivers side front axle and that has probably been causing all of the issues?

And if so, should I go aftermarket, or replace with OEM? I am probably at 500 hp with the Pure 800 and custom tune on 93 octane.

Thanks!

[toxik]

h&r springs are a somewhat aggressive drop for xdrives and the wear on the axles is almost to be expected. if you do go through with swapping it, i really hope it fixes your issue, but in my very un-professional opinion based on the symptoms you described i find it hard to comprehend this being an axle related issue.

id be very curious to know how your car would react to xdelete or any other method of turning off the transfer case and the front diff, where only the rear is in play. but i understand it may not be as easy to achieve that just for curiousity sake.

[CoolATIGuy]

Originally Posted by toxik

h&r springs are a somewhat aggressive drop for xdrives and the wear on the axles is almost to be expected. if you do go through with swapping it, i really hope it fixes your issue, but in my very un-professional opinion based on the symptoms you described i find it hard to comprehend this being an axle related issue.

id be very curious to know how your car would react to xdelete or any other method of turning off the transfer case and the front diff, where only the rear is in play. but i understand it may not be as easy to achieve that just for curiousity sake.

The previous owner installed them, but I believe they are the H&R blue Super Sport lowering springs on front and rear; I believe on sport suspension this drops ~1.3" on the front and 0.7" on the rear

I also have wheel spacers from the previous owner

I do recall the day the issue started happening, hitting a rather large pothole (enough that it still sticks in my mind a couple months later), pretty sure with the drivers side front tire. I'm not positive if it was before the issue started happening, but I do know it was the same day, because I had a 10 hour trip cross country trip that day

I have also hit other potholes before, and with the larger wheels and lowering springs, you can feel it when it happens

What symptoms point you away from thinking the axle being the probable issue?

[toxik]

Originally Posted by CoolATIGuy

The previous owner installed them, but I believe they are the H&R blue Super Sport lowering springs on front and rear; I believe on sport suspension this drops ~1.3" on the front and 0.7" on the rear

I also have wheel spacers from the previous owner

I do recall the day the issue started happening, hitting a rather large pothole (enough that it still sticks in my mind a couple months later), pretty sure with the drivers side front tire. I'm not positive if it was before the issue started happening, but I do know it was the same day, because I had a 10 hour trip cross country trip that day

I have also hit other potholes before, and with the larger wheels and lowering springs, you can feel it when it happens

What symptoms point you away from thinking the axle being the probable issue?

obviously im going by your descriptions more so than actual test driving, but the feeling of shudder and your description of it are all symptoms ive experienced before related to mounts, drivelines, guibos, transfer case. my experience with bad axles is more so knocking and noise, mostly noticeable when turning. but again, im just a dude on the internet, for your sake i'd love to be wrong.

[CoolATIGuy]

Originally Posted by toxik

obviously im going by your descriptions more so than actual test driving, but the feeling of shudder and your description of it are all symptoms ive experienced before related to mounts, drivelines, guibos, transfer case. my experience with bad axles is more so knocking and noise, mostly noticeable when turning. but again, im just a dude on the internet, for your sake i'd love to be wrong.

lol, fair enough

Thanks man!

[CoolATIGuy]

So apparently it was the front driver's side CV joint axle that was the issue - swapped it, and it drives a lot better, no more shuddering

I'm still getting the 1BC11F Gear sensor code, which is throwing chassis stabilization messages too, but it looks like that just happens to be a separate issue - might have to swap that sensor, looking into possibly recalibrating it with ISTA though