4.8 Transmission Logic - Time to fix it or flick it

[LVR]

Well my 4.8 is a real Jekyll and Hyde type of car..... I hate it then I love it

After over a year of persistance I have finally had enough.

It is my daily driver and I am not one who roars around, although that should not mean that this %$%#&$%^*%^%^&*%^%^*%^$%#$@##$$ transmission logic defies my every need.

Each day I have a reasonable inclined road to drive up as I leave my work. From the lights the car is so busy dropping in to top gears that it hasn't noticed that I am going uphill and by now the thing is pinging (detonating) to high heaven.... and I am holding up the cars behind as I am actually slowing down.

All this from a big tough V8. Of course when I give it some more gas (usually lots to wake it up) it erupts in a blaze of sound and fury and next minute I am climbing all over the back of the car in front.

I have tried driving it in sports mode, but that is even worse. The change down points mean that I am doing about 4-5000 rpm in 2nd gear through a round-a-bout.... again a lot of noise for no reason.

There is a street on the way home that has a give way sign, meaning if clear you can continue. I approach it and come to a crawl, next minute it is winding out at 5500rpm in 1st!!!! and all I do is give it a GEEEEENTLE bit of throttle.

I am now switching between normal and sport mode depending on the location and type of corner I am at. What refinement!!!!

Oh, and don't even think of trying to plant the foot and overtake in a hurry...... by the time this big tough V8 has woken up to the fact that you want some squirt it's all over. Great to be all responsive after the event.....

I have had it reprogrammed by the delaer but it obviously learns bad habits all over again.

Can anyone......ANYONE PLEEEEAAAASE suggest a cure before I go and trade this thing in for something else.

[B-A-R]

My 4.8 does alot of the same things, in Sprort. In Drive there is no harsh downshift while braking, but in sport it lunges. I TOO had the dealer load new tranny S/W, it didnt make much of a difference in sport but helped in D a little. Maybe drive around with the mechanic at the dealer and show the symptoms? I might take mine back as well..........b

[X5Jay]

Don't know if I can suggest a cure, by my 4.4 behaves somewhat like your 4.8. When I'm driving around the neighborhood and slow down to turn a corner on a residential street - I'd say down to about 15mph, my 4.4 takes the corner in 4th gear and is bogging coming out of the turn. Then when I get on the gas again, it takes a bit of a push on the gas to get it to downshift and when it does, it certainly doesn't behave like the luxury SAV it's supposed to be. Driving around in manual mode cures it 100% but I wish auto mode was a hell of a lot smarter. It should be taking these slow corners in 3rd gear IMO, not 4th or perhaps even 5th sometimes. And you (I) can forget about sport mode around the neighborhood - 5500 rpms around the hood probably doesn't sit well with the neighbors...

[vinuneuro]

I remember SteveD having various transmission issues as well. Perhaps he might be able to help you a bit. I do know that he is more than satisfied with the replacement 4.8is he got though, as far as the suspension and transmission go.

[Steved]

I'm really not sure what to suggest. I used to have problems and I'd be very conscious of noticing if it ever happened again. However my 2005 4.8is has been absolutely perfect in terms of the transmission/engine logic. It never lunges or surges, it's the model of good behaviour. I drive around most of the time in Sport and it's smooth and responsive, the only time I take it out of Sport is if I'm approaching a junction from speed (just to ensure the gearbox doesn't change any lower than 2nd).

If you are using the latest software then perhaps the 2005 engine/gearbox DMEs work better with the latest software - it could be worth trying to get a replacement DME fitted.

Otherwise, have you had your dealer check for the VANOS Intermediate Valve Lever problem? This is a known PUMA fault item that causes very jerky engine behavoir including moments when the power can virtually cease to deliver.

The UK details are : PUMA 4736767 - dated March 3rd 2005 - Author, John Beckley, Master Technician.

[radioX5]

I just had an upgrade done to my '04 4.8, and it made a huge difference. I don't have the work order here with me at work, but I remember something about an upgraded DME. Before the upgrade, it behaved exactly as yours does.

[LVR]

Originally Posted by radioX5

I just had an upgrade done to my '04 4.8, and it made a huge difference. I don't have the work order here with me at work, but I remember something about an upgraded DME. Before the upgrade, it behaved exactly as yours does.

I would be obliged for details

Otherwise, have you had your dealer check for the VANOS Intermediate Valve Lever problem? This is a known PUMA fault item that causes very jerky engine behavoir including moments when the power can virtually cease to deliver.

The UK details are : PUMA 4736767 - dated March 3rd 2005 - Author, John Beckley, Master Technician.

The local dealership says they cannot find any record of this as it is in the UK.

[radioX5]

giving you everything on my work order b/c i'm not sure what you can use:

CUSTOMER STATES TRANS HAS HESITATION AND SURGES, ACCELERATION RETARDED/CHURNING
1214710 Programming DME data status (with flash EPROM) (with Job No. 13 00 002)
115 WWBX
FC: 1042037100

14466 DROVE VEHICLE INTEROGATED FAULT MEMORY IN EGS AND DME NO FAULTS PRESENT, CHECKED LATEST SIB AND SM FOUND DME NEEDING REPROGRAMMING. REPROGRAMMED DME AND DROVE VEHICLE. OPERATING OK AT THIS TIME.

hopefully this will help

[Steved]

Originally Posted by LVR

I would be obliged for details



The local dealership says they cannot find any record of this as it is in the UK.

LVR, those dealers always say that. It's called laziness. All they have to do is contact BMW Australia and ask them to contact BMW UK and obtain details for the PUMA fault details. There is a system in place designed to facilitate communication within the BMW network.

[LVR]

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..........