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-   -   2005 4.8is transmission shifting / slipping issue (https://xoutpost.com/bmw-sav-forums/x5-e53-forum/100721-2005-4-8is-transmission-shifting-slipping-issue.html)

desertfire 05-19-2015 10:53 PM

2005 4.8is transmission shifting / slipping issue
Firstly, I’d like to say that this forum is an awesome treasure trove of information for anyone who owns an X5 and is a definite asset that all X5 owners should leverage. A lot of good and interesting information.
Recently I “adopted” a 2005 X5 (E53) 4.8is in Imola Red with all the trimmings and options… nothing was spared. It is an absolutely fantastic vehicle and has been kept in pristine condition.

Some info on the vehicle:

· 182k miles
o Nearly all open highway miles
o Previous owner used it as business transport between Michigan and Utah
o Was used for local commuting for < 25k miles through its lifetime
o Previous owner is a mechanical aficionado and installed a run-time clock… engine has 2694 hours on it
· Engine runs like a clock
o Has an amazing (intoxicating) sound when it “wakes up”
o No squealing
o No knocking
o Averages about 24MPG
o No leaks (water or oil)
o Occasionally leaves a puff of smoke when sitting idle for a while
o Doesn’t burn very much oil at all (hasn’t burnt anything noticeable in about 2500 miles)
o Oil was replaced at 9k intervals by original owner
· No electrical issues to report
o Original battery was replaced last week…. (10 years and still going…. ) It didn’t need to be replaced but I did anyway.

Now, on to the issue I am experiencing….
When accelerating it appears that when shifting from 4th to 5th gear the 5th gear catches and then appears to slip out of gear and then the transmission makes a “whizzing” sound, much like a slipping belt and a little like the sound an air ratchet makes when unscrewing a wheel lug (not the hammer part when loosening it). If I let go of the accelerator the gear proceeds to change and things carry on. If I don’t let go of the accelerator the transmission goes into “transmission failsafe program” mode and is basically locked into 3rd gear. If I come to a stop and shut the car off and restart the vehicle the error goes away and things carry on like it hasn’t happened. I have noticed that it happens more when doing a left turn and also when on an upgrade.

Additional details:

· ZF 6HP26 transmission
· Transmission never replaced
· It appears to occur when approaching ~3.5k RPM although has occurred with far less.
· “Garage”shifting from P to R/N/D and back and forth has no issues and does not make any clunking noises. It does take a few seconds for the gear to settle in, but it is not taking an overly long time… (just not crisp) and does not “lurch”.
· In Standard drive mode the problem occurs when shifting from 4th to 5th gear, as far as I can count it.
· In Sport mode the issue doesn’t happen as pronounced and occurs less, but nonetheless occurs.
o One time in Sport mode I didn’t release the gas in time and it went to failsafe mode. It stored a code P17E9 which I have yet to figure out what it relates to. Looked online but haven’t found anything. The code was cleared to see if it was a consistent issue and it has not happened again, although the slipping occurs.
· Another note on the Sport mode is that occasionally a gear will be held for an excessively long time, even if backing off the accelerator, and the only way to release it is to flip back to Standard mode.
· In “Manual” mode the gears shift fine and do not necessarily “slip”. The shifting works well, although it is not paddle-shift quick, but is consistent. There is a little hesitation settling into 4th and 5th but it does not skip out of gear at all.
· No smells or burning of transmission fluid is apparent.

I replaced the transmission fluid to see if the symptoms would alleviate and the transmission appears to run smoother, although the gear shift issue is still occurring. The shift from 1st to 2nd used to hesitate and kick hard when cold but since the fluid change it has been much smoother.
After reading some of the posts on the forum I replaced the battery (the original one apparently was only retaining a 34% charge) and the issue persisted. The alternator checks out fine as well putting out a consistent ~14.2 volts.

I do realize at this point that some work will be needed on the transmission and am not trying to avoid it but am rather interested in understanding what the appropriate fix is for the problem since the issue appears under specific circumstances. Replacing the transmission and torque converter, as much as it is a surefire solution, feels much like shooting a fly with a cannon. I am reserving my judgment on the symptoms as I am no expert in the area of automatic transmissions. I prefer to understand the issue as well as the potential remediation options before jumping into the lion’s den of mechanics that will obviously bleed the issue to the fullest extent they can.

My other vehicle is a 2005 330i ZHP with very low miles and is a joy to drive. It is refreshing to feel that the experience in this variant of the E53 is very sporty. Also, the vehicle has a certain poise and stance that sets it apart from others which inspires me to want to resolve the issue with this vehicle and give it a good rest of its life ahead.
According to a number of other posts there are various areas to look into, such as the MAF sensor, ABS control, Throttle Position Sensor, etc… , but before blindly throwing effort at trying to resolve the problem I am turning to you for support and advice on where to “dig”.

I am very mechanically inclined and will understand any level of technical explanation you may share. Also, if there is any solution that does not involve removing the transmission I will handle it myself as I am fully equipped from a tooling perspective. I don’t have a lift or I would handle the transmission removal as well if required.

Thanks in advance for your help and support!

PropellerHead 05-19-2015 11:17 PM


Originally Posted by desertfire (Post 1038551)
Thanks in advance for your help and support!

Sounds like stuff I was seeing before a transmission service, some small gaskets, and a transmission firmware update. I wrote and others contributed here.

desertfire 05-19-2015 11:37 PM

Thanks Propeller!

Going to jump on the gasket replacement in a week or so after procuring the parts and fluid.

PropellerHead 05-19-2015 11:45 PM


Originally Posted by desertfire (Post 1038557)
Thanks Propeller!

Going to jump on the gasket replacement in a week or so after procuring the parts and fluid.

Look into the firmware update as well. I still had the slip until the firmware was updated.

desertfire 05-19-2015 11:51 PM


Absolutely! I am currently in Carlsbad, CA and it turns out that the son of a good friend of ours runs a beemer indy shop down here and I'm going to reach out to him for running the update. I don't trust the dealership to do what they are expected to do, even though they have been flawless on my 330... just not taking chances...

Looking forward to getting the "5" into shape... love the car!

Also, will post pics of the "pretty lady" once things are in shape ;)

desertfire 06-23-2015 02:57 AM

Ok, an update on the action items for this thread...

I am just now getting back to dealing with this issue after being out of town for several weeks dealing with work... couldn't wait to get into this and figure it out.

I followed the posts that Propeller offered up (kudos Propeller, extremely informative and of awesome help!) and proceeded to execute part 1 of the fix: replacement of the mechatronic "adapter" seals. I replaced the square one as well as the 4 "cylindrical ones. I followed the procedure for draining and opening the transmission and removing the valve body. I wiped down the valve body to remove the black metallic "buildup" that was all over it.. not chunks or shavings, just thick black grime that was a little of everywhere. I'm guessing this is to be expected at 180k miles...

The old main adapter seal for the mechatronic was hardened and the gaskets shriveled. The cylindrical ones were actually shrunk to the point that they had receded into the main transmission body and were no longer even close to making contact with the valve body.

I would upload pictures but am not aware of where is a good place to upload them to where I could grant access to them for this web posting. I'll figure it out at some point...

After replacing the seals and refilling the transmission, the shifting is working far better and is definitely making a huge difference in a large part of the performance.


The "slipping from 4th to 5th is still happening, however, the behavior has become consistent, and the metal whirring sound when the slipping occurs is no longer present, or at least it is not audible. I also learned today that his is called "shift flaring".

The pattern that I can tell is this:

· Drive Mode
o When accelerating at very low throttle, the gears drop fast almost to the point of choking the engine.
o With moderate throttle, the vehicle accelerates through the gears and if the tachometer is right around 2500 rpm, the flaring will occur, consistently.
o With a little more aggressive throttle, pushing the tach to ~3000 rpm the shift issue does not occur, but there is a moment of hesitation
o Going uphill causes the issue to appear more, but I assume that this is caused by needing a little more throttle which causes the system to fail when riding at ~2.5k RPM.
· Sport Mode
o When accelerating at moderate throttle it appears to not happen at a set speed.
o Going uphill apparently causes a hesitation in the shifting between 4th and 5th.
o One time the flare occurred when shifting from 4th to 5th under a little more aggressive acceleration
· Manual Mode
o No issues to report
o The shifting is crisp, very paddle shift speed… makes me want to get a paddle shift steering wheel.
o All gears are held effectively.
o There is a moderate “lurch” forward when the transmission is shifted manually from 2 to 1.

I reached out to the before mentioned “contact” of mine and he gave me the contact info for a ZF transmission “specialist” in San Diego. In speaking with the ZF guru, the contact there basically is saying that at 180K miles repairing the issue may just resolve into something else appearing that may need to be fixed, which may be costly. Also, they don’t repair transmissions, they only overhaul them, so this would basically turn into a transmission rebuild.

Looking at the schematics of the system, from secondary links in one of the posts on Propeller’s forum posting that he linked here, it appears that the only mechanical part in the system that could be causing this level of intermittent behavior would be a failure in the mechatronic valve body since it governs the shift points with the TCM system.

Tomorrow I will be reaching out to My Indie shop contact to verify the firmware on the transmission.

In the meantime, given the updates on the vehicle, does anyone have any idea where to dig on this problem? It is perplexing….

Your feedback is appreciated!

o3x5e53 06-23-2015 09:14 AM

Love a good read. Very informative. Please keep up updated with your problem. I just got my transmission serviced by ZF people here in Australia. They were so shocked on how black it was they were hesitatant to almost actually tell me. 240,000kms worth of dirty transmission fluid

Sounds like transmission problem is such a headache. I hope you get it fixed asap.

Doru 06-23-2015 10:01 AM

Propellerhead suggested to re-flash the tranny.
I also posted the same thing here and some other posts.
Report back after.
P.S. :After re-flashing you should follow the BMW 2-1 tip-in procedure. Basically, take it for a short drive, and EVERY TIME YOU COME TO A STOP, make sure you count to 5. ABSOLUTELY NO ROLLING STOPS. After driving and having 6-7 full stops, turn the vehicle off, wait a few and she's golden.

desertfire 06-23-2015 07:03 PM

Thanks All,

So, latest update....

Just got back from the Indie, Hugo's Euro Auto Repair in Carlsbad, CA, and Rick there dove into the transmission control. Turns out that the firmware is up to date and is matching the checksum of the input firmware image, so all is good there.

There were the following errors stored in the transmission control unit:
- There was one error of slippage between 3rd and 4th
- A fault on clutch pack E

There were no solenoid actuator errors and the test results came back clear for the operation of the Mechatronic.

He cleared the errors and I was on my way out and paid attention to a few details...

1. it seems that the transmission is "hunting" at the specific range of RPM's (~2700) between 3rd and 4th and it would seem to me that the system is trying to decide which of the gears to go with. At one point I had it actually flipping between the two gears constantly while going up hill at moderate gas.

2. When "coasting" under minimal power... like just the tip of gas to carry along... it seems that the transmission releases and engages the gear ever so slightly, but just noticeable.

3. It seems that the engine is choking under load at times... especially when the transmission is upshifting through its gears when under minimal application of accelerator. I would almost assume the system has no idea of where the accelerator is at. Usually I would think of this as a throttle position sensor or MAF sensor not responding, but the system has no indication of this being the issue.

If I were to look at this from a mechanical perspective, I'd say that the hydraulic system is not able to maintain a consistent fluid pressure when spinning under low RPMs, but, if that were the case, wouldn't the system slip when cruising at ~2500 RPM in 6th along the freeway especially uphill?

Also, why does the system seem to work that much better when hitting the throttle just past the ~3k RPM point?

desertfire 06-23-2015 08:40 PM

As an extension to my previous questions, how can I verify that the Torque converter is working correctly ? (i.e. what tests can be done to verify?)


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