Infamous transmission "thunk" after SW upgrade

admranger · #1 06-12-2009, 11:47 PM

Ok, so I did the transmission software upgrade and the "thunk", that nasty 'did I just get hit?' feeling you get when you have the 2-1 downshift (California stop syndrome is what I call it) is still there.

What's the next step for resolution of this fun issue? My X5 is CPO (and the software fix was done under CPO a few weeks ago) so I'm just wondering if anyone has had any luck getting this resolved.

What's sad is that the Allison transmission in my pickup truck is smoother and more responsive than the X5's tranny.

X5 Meister · #2 06-13-2009, 05:40 AM

What SW upgrade did you get done (SIB ?, version # ?, etc.)?

admranger · #3 06-13-2009, 02:21 PM

SIB 24 01 06 was completed. No version number listed on work order.

Defect code 24 00 38 61 00 (text wrapped on work order so I'm not sure if this is the correct number or not).

Thanks!

X5 Meister · #4 06-13-2009, 03:46 PM

That pertains to the August 2007 SIB, too bad it doesn't list a version # since there have been plenty since then. Try a transmission reset.

admranger · #5 06-13-2009, 06:43 PM

I'll try that. I'm hoping the dealer will try a fluid/filter change or something. Save me the hassle!

Weasel · #6 06-13-2009, 07:38 PM

It usually takes clearing all transmission adaptations followed immediately by a nice long test drive to get the initial learnings to be on the conservative side by doing a series of slow easy starts and long slow easy stops. That way it learns the shifts in a smooth pattern vs if you drive it hard after clearing and it wants to shift hard to match that driving style.

admranger · #7 06-13-2009, 08:20 PM

Quote:

Originally Posted by Weasel

It usually takes clearing all transmission adaptations followed immediately by a nice long test drive to get the initial learnings to be on the conservative side by doing a series of slow easy starts and long slow easy stops. That way it learns the shifts in a smooth pattern vs if you drive it hard after clearing and it wants to shift hard to match that driving style.

Ok, I'll try that though it is against my nature to do slow easy starts or stops...

Does it have to learn in sport mode as well as regular mode or will one do it?

admranger · #8 07-07-2009, 04:57 PM

Update. Dropping X5 off at dealer tonight. Was in a parking garage Thursday night going slowly up the ramp when I accelerated a bit. Thought I'd been seriously rear-ended and so did my passengers (WTF was that? was uttered by one of them).

Doing an under vehicle inspection prior to dropping it off I noticed two things (remember, it is a CPO vehicle):

1) one of the exhaust bolts w/the springs is gone (explains the weird noise I hear sometimes), and;

2) the 1/2 shaft joints by the diff (close in, not out by the wheels) are 'wet' with what appears to be diff fluid (very slight leak -- no drips, not thick grease, some "splatter" on undercarraige).

Any chance of linking these to the harsh driveline "thunks"?

Cobra 427 · #9 07-07-2009, 06:31 PM

Hi Kirk,

I have the same problem in my '05 545i, and just recently had the mechatronics valve body replaced in the trasmission (for a different problem), however even after changing the valve body and completely reprogramming the transmission, this "Slam" problem persists. I'm convinced that it is a design flaw that can't be fixed by software.

Check this out: Jaguar S-Type ZF Gearbox Lurch fault

Also do a search on the E60 Forum (E60 Forums?) for "Transmission Slam" (or just "Slam"), then grab some popcorn and start reading...

Good luck,
Randy...

admranger · #10 07-07-2009, 10:48 PM

Quote:

Originally Posted by Cobra 427

Hi Kirk,

I have the same problem in my '05 545i, and just recently had the mechatronics valve body replaced in the trasmission (for a different problem), however even after changing the valve body and completely reprogramming the transmission, this "Slam" problem persists. I'm convinced that it is a design flaw that can't be fixed by software.

Check this out: Jaguar S-Type ZF Gearbox Lurch fault

Also do a search on the E60 Forum (E60 Forums?) for "Transmission Slam" (or just "Slam"), then grab some popcorn and start reading...

Good luck,
Randy...

Thanks Randy. I saw your posts (and others). What a nightmare for BMW (and BMW owners).

BMW needs to work with Allison instead of ZF. The Allison tranny in my truck is buttah smooth. Sooooo much better. There is no comparison.