Tugging or jerking feeling. Misfire? Transmission? Transfer case?

[turboawd]

Originally Posted by JWK170

Well I’m just at 26k miles. Noticed some jerking recently when mid to hard acceleration.

Have seen a lot of comments ranging from plugs/coils to transfer case issues or just the need to change the fluid and reset.

Currently running a JB4 and used the recommended NGK plugs 95770. They only give a 15-20k lifespan which I just hit so I need to replace those anyways. Unfortunately they are on a national backorder so I will have to go with the next step colder. I’m not getting any CEL codes although I’ve read they don’t always show.

Also will check to tread ware to make sure none are way off from the rest.

My last cheap option is to do the transfer case fluid option and reset to see if that does the fix.

Both seem to be the cheapest options and are good preventive maintenance anyways.

Any other suggestions on what it could be or methods to diagnose?

Like you said. Plugs first, especially since you've messed with them before. Then t case fluid.

[Chicane_S54]

Subscribing to this thread because I am getting a similar issue.
A slight tugging or skipping sensation, fells almost like "wheel hop".

NOTE: I started to notice mine recently right after i replaced the OEM 19's
with 20" BBS SX's wrapped with Conti Sport Run Flat's. I am wondering if
these wheels could be the cause of the issue or the issue themselves.

[f15_ride]

I had the same tugging and jerking on my 2014 BMW X5xdrive 501 F15 at 60k. Took it to dealer and they told me I need a new transfer case, the bill was like $7,300. Went to my local guy and they performed a transfer case service/change fluids/reset computer for $150. No issues since. now almost at 80k.

[Hellrot]

I had a similar issue however I got a drivetrain error.

The first time I took it to the dealer they said they couldn't replicate the issue. Error codes showed one misfire.

Of course it happened on my drive home so I took it back.

They eventually diagnosed it as a bad coil, replaced it and I haven't had any issues since.

[ragingpixel]

I had this problem last summer - ended up being a bad coil that was replaced under warranty. Fast forward to this year, and my X5 50i started doing it again - felt like a misfire under heavy acceleration. Took the dealer a while to figure it out this time (no codes), but it ended up being a vacuum leak caused by cracked crankcase ventilation hoses (the plastic ones that get brittle and crack from the heat of the turbos). Replaced with the updated silicone parts (again under warranty), and it's back to running strong.

[ragingpixel]

Originally Posted by ragingpixel

I had this problem last summer - ended up being a bad coil that was replaced under warranty. Fast forward to this year, and my X5 50i started doing it again - felt like a misfire under heavy acceleration. Took the dealer a while to figure it out this time (no codes), but it ended up being a vacuum leak caused by cracked crankcase ventilation hoses (the plastic ones that get brittle and crack from the heat of the turbos). Replaced with the updated silicone parts (again under warranty), and it's back to running strong.

Well... that was short lived. Misfire problem came back a few days later. X5 is back at the dealer. This time they're replacing all 8 plugs and coils. I'm assuming they're just taking shots in the dark at this point, but at least they're starting with the likely suspects. Next up, injectors? We'll see...

[AZTWW]

Originally Posted by ragingpixel

Well... that was short lived. Misfire problem came back a few days later. X5 is back at the dealer. This time they're replacing all 8 plugs and coils. I'm assuming they're just taking shots in the dark at this point, but at least they're starting with the likely suspects. Next up, injectors? We'll see...

Mine ended up being a scored cylinder which meant replacing the whole engine.

[AZTWW]

Originally Posted by ragingpixel

Well... that was short lived. Misfire problem came back a few days later. X5 is back at the dealer. This time they're replacing all 8 plugs and coils. I'm assuming they're just taking shots in the dark at this point, but at least they're starting with the likely suspects. Next up, injectors? We'll see...

Mine ended up being a scored cylinder which meant replacing the whole engine.

[turboawd]

Originally Posted by AZTWW

Mine ended up being a scored cylinder which meant replacing the whole engine.

Wow. You got the v8? How did that happen? A sparkplug break off of something?

[ragingpixel]

Originally Posted by AZTWW

Mine ended up being a scored cylinder which meant replacing the whole engine.

My 4yr/50k expired 3 days ago. Dealer has been trying to solve this issue for the better part of the past month, so I'm not worried about them taking care of it, plus I have another year of CPO coverage. I suppose if the engine is going to go, it might as well be now. But, my guess is that it's far less severe than that.

[AZTWW]

Originally Posted by ragingpixel

My 4yr/50k expired 3 days ago. Dealer has been trying to solve this issue for the better part of the past month, so I'm not worried about them taking care of it, plus I have another year of CPO coverage. I suppose if the engine is going to go, it might as well be now. But, my guess is that it's far less severe than that.

Mine was less than a year out of warranty. BMW had it for a month and goodwilled 75% of the replacement at their cost.

[ragingpixel]

Picked it back up today after they replaced coils and plugs. No sign of the misfire problem on the drive home, and I had a chance to get in some quality "spirited" driving. Feels strong - faster than I remember it. Not ready to call it cured just yet, but cautiously optimistic.

[scarlislek]

2015 BMW X5 x3.5i 70k miles; offset wheels
Posting my results as this thread saved me $5,000!!!

Summary:
Problem: Car started showing signs of a very subtle shudder/stutter/skipping sensation. A little like tires out of balance or driving on ripply pavement.

Resolution: Transfer case issue; I used ISTA+ to do a "Transfer box (VTG): Calibration" , then replaced transfer case fluid and recalibrated again and problem was resolved and has remained resolved for over 5 months.




Details:
Car was running fine for a few years. Front tires getting worn so we only replaced them with new Desert Hawk of the correct factor size. I say "Desert Hawk" b/c I had read where someone else started having this issue after installing those tires. I honestly don't think the brand of tire had anything to do with causing the problem - but rather the car seeing a sudden and dramatic change in tire size and that threw off the calibration of the transfer case clutch. Once we started having the problem, I went ahead and replaced the rear tires also - and that did not change the problem.

Then I started diagnosing...
No light. No codes being thrown.
Problem occurred during acceleration, whether light, moderate or heavy. Problem was intermittent.
Took to a local independent BMW shop in Lawrenceville GA and they diagnosed the problem as clutch wear in transfer case. They said part is not serviceable. A new transfer case w/ labor was about $5,000 to replace.
Took to another independent BMW shop in Suwanee GA and they diagnosed the problem as tires out of balance. They balanced - but we still noticed the issue.

I discovered the wealth of information here and decided to go at it on my own.

I first disconnected the transfer case fuse. For the BMW X5 F10 "Transfer Box (VTG)" Case Fuse is in the passenger wheel well. Fuse #63, 30amp. I pulled the fuse and went for a test ride. Instrument cluster will report "Chassis stabilization: Drive moderately" with the picture of the car swerving (which is how I drive anyway). I test drive showed the problem was GONE!. Okay - so now I know it is related to the transfer case. I have read where people actually unplug the transfer case from under the car. Pulling the fuse seems way easier. I have also read that driving around w/o the transfer case is bad and perfectly fine. I tend to think it is perfectly fine.


The hardest part of the repair was the next step, downloading, installing and gettin to run the ISTA+ software. Search the forums here and everywhere else and just keep installing the dependent packages and it should eventually work. I thought I was being smart and only installed the latest of say some MSFT VC++ Redistributable. Nope ... need to install them all.

I bought the Enet cable needed on Amazon for $18. I bought a "Enet OBD2 Cable,Ethernet OBDII RJ45 Car Diagnostic F-Series Scanner"
For the fluid, again Amazon for $40: Rock Oil TF-0870 IYK500010 Full Synthetic Transfer Case Fluid (1 Liter) for Land Rover LR3, LR4, Range Rover Full Size, and Sport/Sport Supercharged

Once I had the ISTA+ working and ready to do the fluid change, I decided to run ISTA+ and recalibrate before and after changing the fluid. My thinking is that either the fluid change or the re-calibration is likely all that is needed. Not both. But because I didn't test drive the car after the 1st recalibration - but before the fluid change - I really don't know which one did the trick.

To go off on a tangent - what I think happens is the car saw the initial front tire change as a "problem" and decided to fix it with a recalibration and that actually caused the problem. I have no idea why the car doesn't do a recalibration of the transfer case every month or so. Sometimes I think this car is "book smart" - but not real world smart. If someone else does this in the future - it would be good to just either change the fluid or do the recalibration ... but not both and see what fixes the problem.

On the first recalibration, before the fluid change, ISTA+ reported: "Calibration value after the calibration: 22.2 degrees; Difference compared to the previous calibration value: -0.4 degrees"


I jacked up the car and used the tricks noted here (14mm hex inside a wrench) to remove fill plug on transfer case. I didn't have to remove anything else (heat shielding, brackets, etc). I took some stiff tubing I had used for the refrigerator ice make supply line, heated it to create a little hook shape. I was going to use a vacuum pump to pull out he liquid, but since I had gravity on my side, a little syphon on the tubing to get fluid over the hump and gravity did the rest. It took about 15mins to pull out as much as I could I got 600ml, Used fluid was dark - but I didn't see any gremlins in it. I pumped new fluid in until it overflowed out the fill hole. Tightened plug.

The did another recalibration with ISTA+. On the second recalibration, the system reported the same 22.2 degrees and 0.0 degrees of difference. So the new fluid didn't seem to require a recalibration.

That was it. Since then it has never exhibited the shudder again. I guess I'll plan to do this after another 70k miles.

[Maverik259]

Originally Posted by scarlislek

2015 BMW X5 x3.5i 70k miles; offset wheels
Posting my results as this thread saved me $5,000!!!

Summary:
Problem: Car started showing signs of a very subtle shudder/stutter/skipping sensation. A little like tires out of balance or driving on ripply pavement.

Resolution: Transfer case issue; I used ISTA+ to do a "Transfer box (VTG): Calibration" , then replaced transfer case fluid and recalibrated again and problem was resolved and has remained resolved for over 5 months.




Details:
Car was running fine for a few years. Front tires getting worn so we only replaced them with new Desert Hawk of the correct factor size. I say "Desert Hawk" b/c I had read where someone else started having this issue after installing those tires. I honestly don't think the brand of tire had anything to do with causing the problem - but rather the car seeing a sudden and dramatic change in tire size and that threw off the calibration of the transfer case clutch. Once we started having the problem, I went ahead and replaced the rear tires also - and that did not change the problem.

Then I started diagnosing...
No light. No codes being thrown.
Problem occurred during acceleration, whether light, moderate or heavy. Problem was intermittent.
Took to a local independent BMW shop in Lawrenceville GA and they diagnosed the problem as clutch wear in transfer case. They said part is not serviceable. A new transfer case w/ labor was about $5,000 to replace.
Took to another independent BMW shop in Suwanee GA and they diagnosed the problem as tires out of balance. They balanced - but we still noticed the issue.

I discovered the wealth of information here and decided to go at it on my own.

I first disconnected the transfer case fuse. For the BMW X5 F10 "Transfer Box (VTG)" Case Fuse is in the passenger wheel well. Fuse #63, 30amp. I pulled the fuse and went for a test ride. Instrument cluster will report "Chassis stabilization: Drive moderately" with the picture of the car swerving (which is how I drive anyway). I test drive showed the problem was GONE!. Okay - so now I know it is related to the transfer case. I have read where people actually unplug the transfer case from under the car. Pulling the fuse seems way easier. I have also read that driving around w/o the transfer case is bad and perfectly fine. I tend to think it is perfectly fine.


The hardest part of the repair was the next step, downloading, installing and gettin to run the ISTA+ software. Search the forums here and everywhere else and just keep installing the dependent packages and it should eventually work. I thought I was being smart and only installed the latest of say some MSFT VC++ Redistributable. Nope ... need to install them all.

I bought the Enet cable needed on Amazon for $18. I bought a "Enet OBD2 Cable,Ethernet OBDII RJ45 Car Diagnostic F-Series Scanner"
For the fluid, again Amazon for $40: Rock Oil TF-0870 IYK500010 Full Synthetic Transfer Case Fluid (1 Liter) for Land Rover LR3, LR4, Range Rover Full Size, and Sport/Sport Supercharged

Once I had the ISTA+ working and ready to do the fluid change, I decided to run ISTA+ and recalibrate before and after changing the fluid. My thinking is that either the fluid change or the re-calibration is likely all that is needed. Not both. But because I didn't test drive the car after the 1st recalibration - but before the fluid change - I really don't know which one did the trick.

To go off on a tangent - what I think happens is the car saw the initial front tire change as a "problem" and decided to fix it with a recalibration and that actually caused the problem. I have no idea why the car doesn't do a recalibration of the transfer case every month or so. Sometimes I think this car is "book smart" - but not real world smart. If someone else does this in the future - it would be good to just either change the fluid or do the recalibration ... but not both and see what fixes the problem.

On the first recalibration, before the fluid change, ISTA+ reported: "Calibration value after the calibration: 22.2 degrees; Difference compared to the previous calibration value: -0.4 degrees"


I jacked up the car and used the tricks noted here (14mm hex inside a wrench) to remove fill plug on transfer case. I didn't have to remove anything else (heat shielding, brackets, etc). I took some stiff tubing I had used for the refrigerator ice make supply line, heated it to create a little hook shape. I was going to use a vacuum pump to pull out he liquid, but since I had gravity on my side, a little syphon on the tubing to get fluid over the hump and gravity did the rest. It took about 15mins to pull out as much as I could I got 600ml, Used fluid was dark - but I didn't see any gremlins in it. I pumped new fluid in until it overflowed out the fill hole. Tightened plug.

The did another recalibration with ISTA+. On the second recalibration, the system reported the same 22.2 degrees and 0.0 degrees of difference. So the new fluid didn't seem to require a recalibration.

That was it. Since then it has never exhibited the shudder again. I guess I'll plan to do this after another 70k miles.

Great info. Would be doing this myself if the dealer didn't offer to replace mine under my extended warranty. Just cAnt turn down a new one for a fluid change haha.

Also curious about the fuse vice unplugging. Assume even if unplugged you get the same chassis unstable warning. I got 3 weeks until my appointment and want to pull this fuse until then but also don't want the dealer to throw some garbage at me saying I caused some future issue by doing this.

[Maverik259]

Found this fuse box diagram just for anyone else looking to do this. Interestingly enough my box wasn't exact but still easy enough to line up which is which.

[M302_imola]

Originally Posted by scarlislek

2015 BMW X5 x3.5i 70k miles; offset wheels
Posting my results as this thread saved me $5,000!!!

Summary:
Problem: Car started showing signs of a very subtle shudder/stutter/skipping sensation. A little like tires out of balance or driving on ripply pavement.

Resolution: Transfer case issue; I used ISTA+ to do a "Transfer box (VTG): Calibration" , then replaced transfer case fluid and recalibrated again and problem was resolved and has remained resolved for over 5 months.




Details:
Car was running fine for a few years. Front tires getting worn so we only replaced them with new Desert Hawk of the correct factor size. I say "Desert Hawk" b/c I had read where someone else started having this issue after installing those tires. I honestly don't think the brand of tire had anything to do with causing the problem - but rather the car seeing a sudden and dramatic change in tire size and that threw off the calibration of the transfer case clutch. Once we started having the problem, I went ahead and replaced the rear tires also - and that did not change the problem.

Then I started diagnosing...
No light. No codes being thrown.
Problem occurred during acceleration, whether light, moderate or heavy. Problem was intermittent.
Took to a local independent BMW shop in Lawrenceville GA and they diagnosed the problem as clutch wear in transfer case. They said part is not serviceable. A new transfer case w/ labor was about $5,000 to replace.
Took to another independent BMW shop in Suwanee GA and they diagnosed the problem as tires out of balance. They balanced - but we still noticed the issue.

I discovered the wealth of information here and decided to go at it on my own.

I first disconnected the transfer case fuse. For the BMW X5 F10 "Transfer Box (VTG)" Case Fuse is in the passenger wheel well. Fuse #63, 30amp. I pulled the fuse and went for a test ride. Instrument cluster will report "Chassis stabilization: Drive moderately" with the picture of the car swerving (which is how I drive anyway). I test drive showed the problem was GONE!. Okay - so now I know it is related to the transfer case. I have read where people actually unplug the transfer case from under the car. Pulling the fuse seems way easier. I have also read that driving around w/o the transfer case is bad and perfectly fine. I tend to think it is perfectly fine.


The hardest part of the repair was the next step, downloading, installing and gettin to run the ISTA+ software. Search the forums here and everywhere else and just keep installing the dependent packages and it should eventually work. I thought I was being smart and only installed the latest of say some MSFT VC++ Redistributable. Nope ... need to install them all.

I bought the Enet cable needed on Amazon for $18. I bought a "Enet OBD2 Cable,Ethernet OBDII RJ45 Car Diagnostic F-Series Scanner"
For the fluid, again Amazon for $40: Rock Oil TF-0870 IYK500010 Full Synthetic Transfer Case Fluid (1 Liter) for Land Rover LR3, LR4, Range Rover Full Size, and Sport/Sport Supercharged

Once I had the ISTA+ working and ready to do the fluid change, I decided to run ISTA+ and recalibrate before and after changing the fluid. My thinking is that either the fluid change or the re-calibration is likely all that is needed. Not both. But because I didn't test drive the car after the 1st recalibration - but before the fluid change - I really don't know which one did the trick.

To go off on a tangent - what I think happens is the car saw the initial front tire change as a "problem" and decided to fix it with a recalibration and that actually caused the problem. I have no idea why the car doesn't do a recalibration of the transfer case every month or so. Sometimes I think this car is "book smart" - but not real world smart. If someone else does this in the future - it would be good to just either change the fluid or do the recalibration ... but not both and see what fixes the problem.

On the first recalibration, before the fluid change, ISTA+ reported: "Calibration value after the calibration: 22.2 degrees; Difference compared to the previous calibration value: -0.4 degrees"


I jacked up the car and used the tricks noted here (14mm hex inside a wrench) to remove fill plug on transfer case. I didn't have to remove anything else (heat shielding, brackets, etc). I took some stiff tubing I had used for the refrigerator ice make supply line, heated it to create a little hook shape. I was going to use a vacuum pump to pull out he liquid, but since I had gravity on my side, a little syphon on the tubing to get fluid over the hump and gravity did the rest. It took about 15mins to pull out as much as I could I got 600ml, Used fluid was dark - but I didn't see any gremlins in it. I pumped new fluid in until it overflowed out the fill hole. Tightened plug.

The did another recalibration with ISTA+. On the second recalibration, the system reported the same 22.2 degrees and 0.0 degrees of difference. So the new fluid didn't seem to require a recalibration.

That was it. Since then it has never exhibited the shudder again. I guess I'll plan to do this after another 70k miles.

Thank you so much for posting! I believe I'm having the same issue as you had. Mine started when I replaced my rear tires w/ new while keeping the 50% tread left older tires on the front. Fyi, I'm running 295/30/R22 front and 335/25/R22 back. So at full tread on both front and rear there's about a 1% difference in overall circumference, which doesn't sound like much but from my reading our TC's are very sensitive. Anyhow, not only do I feel what appears to be a tire out of balance feeling, during relatively hard cornering my traction control light will flicker and engage. Almost feels like you're going to lose control of the car. I have a feeling the sensitivity of the transfer case is provoking this. If I turn of DSC then I can corner hard without the "floaty feeling". I've decided to get new tires so I'm going to go with 285/30/R22 front this time with 335/25/R22 rear. The fronts put me very close to the same circumference as the rears so the TC should like this more. But your thread has me thinking a fluid change and recalibration might be in order. So sound like the ISTA+ is required for the recalibration correct? You didn't bother changing transmission fluid (new pan) at the same time of the TC fluid change. Any reasoning? I have to say that I've thought about just changing the TC fluid, but having to use the ISTA+ is where I get nervous. I have a ethernet to obd and obd to lightning connectors. What else would i need to do the TC recalibration? Where did you buy the TC fluid from? Really appreciate your post.

[skoold2003]

Originally Posted by M302_imola

Thank you so much for posting! I believe I'm having the same issue as you had. Mine started when I replaced my rear tires w/ new while keeping the 50% tread left older tires on the front. Fyi, I'm running 295/30/R22 front and 335/25/R22 back. So at full tread on both front and rear there's about a 1% difference in overall circumference, which doesn't sound like much but from my reading our TC's are very sensitive. Anyhow, not only do I feel what appears to be a tire out of balance feeling, during relatively hard cornering my traction control light will flicker and engage. Almost feels like you're going to lose control of the car. I have a feeling the sensitivity of the transfer case is provoking this. If I turn of DSC then I can corner hard without the "floaty feeling". I've decided to get new tires so I'm going to go with 285/30/R22 front this time with 335/25/R22 rear. The fronts put me very close to the same circumference as the rears so the TC should like this more. But your thread has me thinking a fluid change and recalibration might be in order. So sound like the ISTA+ is required for the recalibration correct? You didn't bother changing transmission fluid (new pan) at the same time of the TC fluid change. Any reasoning? I have to say that I've thought about just changing the TC fluid, but having to use the ISTA+ is where I get nervous. I have a ethernet to obd and obd to lightning connectors. What else would i need to do the TC recalibration? Where did you buy the TC fluid from? Really appreciate your post.

I got my TC fluid from FCPEURO because I plan to do it again in another 50k. Also you just need the OBD to Ethernet and ISTA.

[M302_imola]

Originally Posted by skoold2003

I got my TC fluid from FCPEURO because I plan to do it again in another 50k. Also you just need the OBD to Ethernet and ISTA.

Thanks. So is the ISTA downloadable or can it be purchased on amazon?

[skoold2003]

Originally Posted by M302_imola

Thanks. So is the ISTA downloadable or can it be purchased on amazon?

ISTA+ Download Link https://f15.bimmerpost.com/forums/sh....php?t=1568962

[Tonyman]

Originally Posted by skoold2003

ISTA+ Download Link https://f15.bimmerpost.com/forums/sh....php?t=1568962

Same exact issue. Just disconnected the transfer box fuse and the issue went away.

What oil should I use for my X5 Diesel? It’s 2015.

Thanks!

[crystalworks]

I also have this issue. Coming up on new tires being needed so will get new tires and do the Xfer case fluid/reset at that time. Thanks to everyone for documenting this.

[M302_imola]

Originally Posted by scarlislek

2015 BMW X5 x3.5i 70k miles; offset wheels
Posting my results as this thread saved me $5,000!!!

Summary:
Problem: Car started showing signs of a very subtle shudder/stutter/skipping sensation. A little like tires out of balance or driving on ripply pavement.

Resolution: Transfer case issue; I used ISTA+ to do a "Transfer box (VTG): Calibration" , then replaced transfer case fluid and recalibrated again and problem was resolved and has remained resolved for over 5 months.




Details:
Car was running fine for a few years. Front tires getting worn so we only replaced them with new Desert Hawk of the correct factor size. I say "Desert Hawk" b/c I had read where someone else started having this issue after installing those tires. I honestly don't think the brand of tire had anything to do with causing the problem - but rather the car seeing a sudden and dramatic change in tire size and that threw off the calibration of the transfer case clutch. Once we started having the problem, I went ahead and replaced the rear tires also - and that did not change the problem.

Then I started diagnosing...
No light. No codes being thrown.
Problem occurred during acceleration, whether light, moderate or heavy. Problem was intermittent.
Took to a local independent BMW shop in Lawrenceville GA and they diagnosed the problem as clutch wear in transfer case. They said part is not serviceable. A new transfer case w/ labor was about $5,000 to replace.
Took to another independent BMW shop in Suwanee GA and they diagnosed the problem as tires out of balance. They balanced - but we still noticed the issue.

I discovered the wealth of information here and decided to go at it on my own.

I first disconnected the transfer case fuse. For the BMW X5 F10 "Transfer Box (VTG)" Case Fuse is in the passenger wheel well. Fuse #63, 30amp. I pulled the fuse and went for a test ride. Instrument cluster will report "Chassis stabilization: Drive moderately" with the picture of the car swerving (which is how I drive anyway). I test drive showed the problem was GONE!. Okay - so now I know it is related to the transfer case. I have read where people actually unplug the transfer case from under the car. Pulling the fuse seems way easier. I have also read that driving around w/o the transfer case is bad and perfectly fine. I tend to think it is perfectly fine.


The hardest part of the repair was the next step, downloading, installing and gettin to run the ISTA+ software. Search the forums here and everywhere else and just keep installing the dependent packages and it should eventually work. I thought I was being smart and only installed the latest of say some MSFT VC++ Redistributable. Nope ... need to install them all.

I bought the Enet cable needed on Amazon for $18. I bought a "Enet OBD2 Cable,Ethernet OBDII RJ45 Car Diagnostic F-Series Scanner"
For the fluid, again Amazon for $40: Rock Oil TF-0870 IYK500010 Full Synthetic Transfer Case Fluid (1 Liter) for Land Rover LR3, LR4, Range Rover Full Size, and Sport/Sport Supercharged

Once I had the ISTA+ working and ready to do the fluid change, I decided to run ISTA+ and recalibrate before and after changing the fluid. My thinking is that either the fluid change or the re-calibration is likely all that is needed. Not both. But because I didn't test drive the car after the 1st recalibration - but before the fluid change - I really don't know which one did the trick.

To go off on a tangent - what I think happens is the car saw the initial front tire change as a "problem" and decided to fix it with a recalibration and that actually caused the problem. I have no idea why the car doesn't do a recalibration of the transfer case every month or so. Sometimes I think this car is "book smart" - but not real world smart. If someone else does this in the future - it would be good to just either change the fluid or do the recalibration ... but not both and see what fixes the problem.

On the first recalibration, before the fluid change, ISTA+ reported: "Calibration value after the calibration: 22.2 degrees; Difference compared to the previous calibration value: -0.4 degrees"


I jacked up the car and used the tricks noted here (14mm hex inside a wrench) to remove fill plug on transfer case. I didn't have to remove anything else (heat shielding, brackets, etc). I took some stiff tubing I had used for the refrigerator ice make supply line, heated it to create a little hook shape. I was going to use a vacuum pump to pull out he liquid, but since I had gravity on my side, a little syphon on the tubing to get fluid over the hump and gravity did the rest. It took about 15mins to pull out as much as I could I got 600ml, Used fluid was dark - but I didn't see any gremlins in it. I pumped new fluid in until it overflowed out the fill hole. Tightened plug.

The did another recalibration with ISTA+. On the second recalibration, the system reported the same 22.2 degrees and 0.0 degrees of difference. So the new fluid didn't seem to require a recalibration.

That was it. Since then it has never exhibited the shudder again. I guess I'll plan to do this after another 70k miles.

I just installed 4 new tires which cured my problem of the traction control flickering under moderate cornering. But I have an intermediate vibration/shudder at highway speeds now. I first thought, they didn't balance the wheel/tires correctly, but after re-reading your post I think I'm having the same issue as you. The TC recalibrated when I had worn front tires w/ new rears and now that all 4 are replaced it needs recalibrated. I'm going to pull the TC fuse like you did and see then go from there.