[possum300d]

Hi.

I recently purchased a 2012 F25 X3 with 155k miles on it which came up for sale at a good price. I already have another 2012 X3 with 180k miles (which has been a brilliant car) so knew what I was potentially letting myself in for. Anyhow, on the long journey home I noted a sight shudder in gears 3, 4 and 5 only between 1200 an 1800 rpm under light load.

Having previous experience with a similar symptom I knew this was likely transmission related. During fault finding I pulled the fuse for the transfer case actuator (VTG) which greatly improved the situation and introduced me to my first encounter with a transfer case failure; so I have ordered parts to rebuild the transfer case clutch pack. I am mechanically competent enough to carry out work like this.

With the transfer case disabled, a slight shudder remained. As stated above; in gears 3,4 and 5 only under light acceleration only and between 1200 and 1800 rpm. If I accelerate briskly everything is fine, if I load the torque converter up in high gears at low RPM pulling through the rev range nothing slips.

I carried out filter pan and oil change but no difference. I carried transmission adaptation reset which improved things a little but only for a short time. The adaption values are well within spec after 60+ miles; although Clutch D still shows 0.0 mbar. Is this normal?

I figured that the next cause would likely be a common clutch pack but now having found a P&ID for the ZF 8HP I can see that the clutch packs cover more than just the three affected gears including gears that show no issues. The solenoid valves are the same, covering more than just the three affected gears.

My usual methodical fault finding skills are struggling to identify the next step here. Where can you guys assist me with this?

Thanks in advance.

[bmwPower99]

I would get the car to temp and open the trany fill bolt (while car level). If fluid doesn't come out then you underfilled, which can cause hesition.

[possum300d]

Originally Posted by bmwPower99

I would get the car to temp and open the trany fill bolt (while car level). If fluid doesn't come out then you underfilled, which can cause hesition.

Thanks my man.

I followed the procedure to the letter with final level check being completed at just under 50°C; but you're right, another check after these miles wouldn't go a miss.

Given it displaying same symptoms prior to filter/fluid change I unfortunately don't think it will be level related.

Thanks

[bmwPower99]

Try an accelerator pedal reset. This issue seems fairly well known in other Models, caused by driving like a granny
"It's dependent on driving style whether or not the issue presents itself. It generally only presents itself on drivers whom are very conservative. The transmission learns the driving habits and ends up in very high gears at low speeds. The vibration only exists at very low RPM's in higher gears. But I can assure you, you can make any F10/F01 do this if you try. Most people will never notice it/drive in a way that it will present itself. I worked for BMW for four years and we saw it all the time. It is something in the driveline that is not balanced correctly." https://f10.5post.com/forums/showthread.php?t=1235711

You could also check you guibo,central prop bearing and even harmonic balancer.

[Opie55]

Since disabling the transfer case improved things, did you check the prop shaft from the transfer case to the front diff?

[possum300d]

Originally Posted by Opie55

Since disabling the transfer case improved things, did you check the prop shaft from the transfer case to the front diff?

Hmm... thats food for thought. I did notice the vehicle had a new front propshaft on it. This could potentially highlight that the splines on the transfer case output shaft are slipping? Perhaps been dressed up to look good by prior owner before sale.

I will need to check that for sure. Thinking metal shavings would have been evident in the area and I certainly can't remember any noise etc.

Thanks for the input.

[heticor]

Check this video since minute 33. there a procedure to fix some transmission issues.

[Dekero]

You're going to think I'm nuts...

But add 2 tubes of Shudder FIXX to the transmission
Mine was doing the same thing... This stuff solved it...

Now I've added 2 tubes each time I change the fluids...


Lubegard 19610 Dr. Tranny Instant Shudder Fixx, 2 Oz. Count 1(Pack of 1) https://a.co/d/iRcg0kS

[possum300d]

OK, so that's the transfer case been rebuilt with a new clutch pack and the VGT actuator recalibrated by my Foxwell tool.

While in the air I changed the gearbox fluid for a second time. The shudder in gears 3,4 and 5 is just as bad if not worse than it was 1500 miles ago. I guess I will try the tubes of Shudder Fixx as suggested.

However I still think there must surely be a way to get to the route cause of the situation here. I'd be willing to spend money if only I could diagnose the cause properly as the rest of the car runs well.

Any pointers from those with experience?

[possum300d]

Originally Posted by Dekero

You're going to think I'm nuts...

But add 2 tubes of Shudder FIXX to the transmission
Mine was doing the same thing... This stuff solved it...

Now I've added 2 tubes each time I change the fluids...


Lubegard 19610 Dr. Tranny Instant Shudder Fixx, 2 Oz. Count 1(Pack of 1) https://a.co/d/iRcg0kS

Thanks, will give this a try.

[possum300d]

Originally Posted by Dekero

You're going to think I'm nuts...

But add 2 tubes of Shudder FIXX to the transmission
Mine was doing the same thing... This stuff solved it...

Now I've added 2 tubes each time I change the fluids...


Lubegard 19610 Dr. Tranny Instant Shudder Fixx, 2 Oz. Count 1(Pack of 1) https://a.co/d/iRcg0kS

Well... two tubes of Lubeguard Instant Shudder Fixx and the shudder is gone!

Guessing it must be the torque converter; so strange that its only in those 3 gears!

How many miles have you done with this issue apparent?

Hoping its not going to return in another 1000 miles.

[Dekero]

Told you!!! That stuff is amazing!!

Glad it worked !!

The shudder is on my X5 and I'm at 250k miles and just changed the fluid again... Added 3 tubes... Well just because and it drives flawlessly!

[gong03.memory@icloud.com]

I have a very similar problem;
Shuddering at 1,200 - 1,800 rpm especially uphill, low revs (driving like I’m about to run out of fuel)
Starting at a stop feels like I’m in too low a gear, so I push on the acellerator, but it seems like I’m braking, then after 2 seconds it suddenly downshifts and jumps forward.

The problem is with the transfer case actuator gear. A very cheap part, like $20.

[AndresReyesDev]

Originally Posted by gong03.memory@icloud.com

I have a very similar problem;
Shuddering at 1,200 - 1,800 rpm especially uphill, low revs (driving like I’m about to run out of fuel)
Starting at a stop feels like I’m in too low a gear, so I push on the acellerator, but it seems like I’m braking, then after 2 seconds it suddenly downshifts and jumps forward.

The problem is with the transfer case actuator gear. A very cheap part, like $20.

Correct but for E83. This specific model (F25) has a different part and you need to replace the whole actuator. You cannot access to that gear just like that. The part for this model F25 is called Longitudinal Torque Module and is the same with a different name for the Transfer Case Actuator.