4.8 Transmission Logic - Time to fix it or flick it - Page 2

LVR · #11 02-16-2006, 04:26 AM

oh damn..... what to do.... what to do

Having given the matter some thought I decided to trade both X5's in, and get an X3 for the little lady and an E60 550 for myself, thinking that that will solve the problem.

I hopped on over to the 5 series forums and it seems they are having it even worse! they are having transmission SLAM that means the car revs up to 5000 rpm then engages the drive jerking the whole car... or upshifts when slowing down. doing the same as you almost come to a stop.

It seems that the transmission operates on an extreme economy (XE) or economy (E) mode otherwise it has to be in sport (S) or extreme Sport (XS) ie manual mode. Gear change points are determined by the input signals from the accelerator pedal, cornering detection and brake evaluation. My problem appears to be in the values used for uphill or trailer towing. Theoretically, the normal level road situation is calculated against the load being detected and the uphill or towing function is activated. This is supposed to eliminate undesired upshifts and frequent up/downshifts.

In theory......

I can't believe BMW can sell this kind of s%$# ..............and I am a fan!

maybe it's time to look at a porsche..........

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fangbosun · #12 02-16-2006, 09:00 AM

Just superceded M5? it only comes in manual!!!

x5fromOz · #13 02-18-2006, 02:22 AM

Having recently replaced my auto trans in my 4.4 with a new one, I cant understand how it is that my wifes Subaru Forester X is so nice to drive with smooth auto shifts and never anything to repair at service time....beats me as to why we keep coming back for more??? Maybe it is becuase somebody once said , in this country, that "Life was not meant to be easy".

LVR · #14 03-02-2006, 08:45 AM

took mr hyde down to the dealer today and got him all reprogrammed.....

has returned to me a very different car, holds gear going up hill, only drops back one gear when needed depending on throttle pressure

as an aside, I found out that you can only do 16 reprogrammes of the car computer then you have to get a new one..... bit of a drama if you have a constant problem.

oh well, we shall see what transpires

Rboosted717 · #15 05-04-2006, 03:14 AM

Sorry to bring this topic from the dead, but I am having <b>HUGE</b> issues with my '04 4.8is transmission software.

A month ago, I brought my 4.8is in for service because the transmission would make a groan noise when the transmission downshifted during acceleration. When I received the truck back, I was told that they could not reproduce the noise; however, according to the paper work they did the following:

"customer states transmission is noisy when up/down shifting at mid/high throttle load. EGS programming faulty per SI 24 01 06. Test drove car and during the 2-1 downshift the transmission would shift very hard. Put car on DIS and checked for faults, found none relating to complaint. Checked for and SI's and found SI 24 01 06 which states to reprogram trans control module if customer complains about harsh downshift or bang noise when shifting. So I reprogrammed the EGS on the programming station per SI 24 01 06. Test drove afterwards, all was fine"

After receiving the 4.8is back, the noise I complained about was still occurring and now the performance/driveability feels like crap. The transmission will no longer downshift when slowing down and when driving around town the transmission keeps up shifting into the next highest gear at low speeding causing horrible responsiveness which makes me have to almost floor the accelerator pedal to make it accelerate or downshift like it use to do.

The following week I brought the 4.8is back in for another try. Additionally, this time I have the shop foreman a test drive. Amazingly, the shop foreman heard the groan noise I was talking about and said he would look into the odd/peculiar noise immediately. As for the horrible performance after the UNNEEDED or UNWANTED software update, he informed me that they are unable to go back to my old software program, so I would have to live with the way it is now. Additionally, he said if I drive the truck harder, it should feel better after the programming (AGS) has time to readjust to my driving habits over the next few days/weeks (total bullshit seeing the AGS never stores the information after shut-down, it is dynamic, not static). He also stated that he would try to reflash the updated software program to see if that helps with the way the transmission feels.

When I got my truck back the second time I found the following notes:
"c/s that there is a groan noise when trans d/s w c/s that there is a groan noise when trans downshifted. test drove vehicle with shop foreman, found howling type noise present when vehicle downshifts and accelerated (3-2). Foreman then suggested to write PUMA case. Wrote PUMA case and waiting for response. Received response. PUMA response case #5259347. Advised to drain fluid, let cool for an hour, refill, start engine, top off. Run at 1500 rpm for 2 minutes, shut off and drain again. Let cool and refill with fresh fluid. Top off after filling. Clear adaptations and drive. Performed what PUMA suggested. Noise have been eliminated after test driving. Shop foreman ok'd repairs"

Amazingly, this fix seemed to have solved the strange noise! However, as for the software update per the HORRIBLE performance/drivability, I found the follwing notes:

"c/s that trans goes into coast after software chg. advised by shop foreman to reprogram vehicle again and clear adaptations. per SIB 24 01 06, attempted to reprogram vehicle with sss, vehicle does not connect after multiple time. after 4th time trying to program with sss, vehicle programmed with CIP 21.0. Cleared faults and adaptations. Test drove, advise that vehicle now runs normally."

Sadly, this did NOT fix the problem. In fact, each day I drive the X5, I hate it more and more, so much that I have not really driven it in the past 3-4weeks.

After driving a friends '04 4.8is today (exactly same as mine), I realized how screwed up my truck really is. First off, my truck NEVER downshifts anymore when slowing down like it use to do. Additionally, the transmission ALWAYS goes into top gear or neutral if I am not on the gas. Also, in order to get any responsiveness from the motor, I now have to floor the gas pedal to the point of the "kick down" switch for any real acceleration to happen. Also, even when in "sport" mode or manually shifting the transmission, I can never get the transmission to decelerate and downshift like it use to do. Normally when it would downshift when slowing it would give the passengers/driver a negative G feeling as the transmission slowed the motor. However now when it downshifts, the motor just rev's with no "negative G force feeling." It almost feeling like the new software is in "numb" mode because it removes all feeling of acceleration, deceleration, downshifting deceleration, etc... What really sucks is that when I would go into a turn and let off the gas, the transmission would hold the gear or a similar gear to keep the rev’s up and the power/trq balancing the load on the tires. However now when I enter a turn and let off the gas, the transmission either goes into the highest possible gear or goes into neutral until I get back on the gas! This is the stupidest feeling transmission software ever!

What really stinks is that the dealership told me the software update is not backwards capable, meaning it can only update with new software, not older software. I really do not know what to do. The only thing that is keeping my head on is being able to drive my new SRT8 Jeep because the 4.8is now feels/drives like crap!
Any ideas?

vinuneuro · #16 05-04-2006, 03:24 AM

Seems like the vehicle qualifies as a lemon at this point.

f355b · #17 05-04-2006, 08:20 AM

wow i have a 2004 4.8 and it drives beautiful only thing to do is back it.

rss4.8is · #18 05-04-2006, 09:54 AM

If you want a performance engine and car I would think it could be a bit lungy or torquey...My 05 4.8 seems to be fine and its all in how you handle the gas pedal in certain situations depending on type of road , speed and drive mode you are in...

f355b · #19 05-04-2006, 10:00 AM

the only thing you cant do is put it in sports mode and pull away fast then brake hard and hit the gas again as it holds first gear....then it feels jerky but apart from that never had a problem i also have a SSG wheel and i only change gear in sports mode with this car dives like a dream best mod out there IMO.

LVR · #20 05-07-2006, 01:27 AM

I'm hearing you......

Everything you are describing is what i have been through. What I discovered though, is that the transmission (via the central control module) takes readings from so many other areas that measure yaw/braking pressure/pitch/steering angle/accelerator position etc that re flashing the software for the transmission is only 'half' the job.

In order to get everything reset, I had to have the central control computer re-flashed as well as the transmission.

This has eliminated the 'being caught in the wrong gear' feel that I had and it now works its' way up and down the gears as it should, rather than dropping straight into top as quickly as possible.

I would suggest you go back and get the control module done as well at the same time.

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