# OF GEARS

[Reuben]

i was interested in knowing how many gears are in the standard automatic tramision on the 04 models 4 or 5 ?

 

[Andy]

Isn't the prefacelift Auto (pre 2006) 5 Speed, but the Facelift is 6 speed?

Someone will be along in a second to answer that for sure

 

[Wondermike]

Correct

 

[PawnSacrifice]

I was doing my research, come back and Wondermike has confirmed that Andy is, of course, correct

Anyway, I've done the legwork so here's my findings from Parkers (using 3.0i as standard for pre-facelift and 3.0si Sport as facelift model)...

3.0i Auto with 5 speed Auto
http://www.parkers.co.uk/cars/specs/Detail.aspx?deriv=25020

3.0si Sport Auto with 6 speed Auto
http://www.parkers.co.uk/cars/specs/Detail.aspx?deriv=33123

 

[lacroupade]

Just for interest is it a genuine 6-speeder or 3 with O/D?

 

[Wondermike]

It's a genuine six speeder, very advanced!

ZF GA6HP19Z

The gearbox has 13 separate functions, but I'll only go into more detail on the Adaptive Transmission Control. the other functions are Overlap control, Starter inhibitor, Parking lock, Warming-up program, Engine intervention, Downshift inhibitor, Reverse gear inhibitor, Selector lever lock (shiftlock), Standstill decoupling, Interlock, Emergency program, Rock free from snow function.

The Adaptive transmission control is interesting though. As with earlier transmissions the 6-speed box provides the choice between comfort ('D') and sport ('DS') programs.

However, did you know that there are two separate maps for each program? These maps are compiled based on driver inputs (throttle, yaw rate, brake & deceleration etc) but in both programs the adaptive transmission changes from a basic economy map to a more performance oriented map.

In selector lever position 'D' there is an XE map (extreme economy) and an E map (economy). The EGS control unit normally selects the XE map, but in case of particular demands (e.g. load requirements) it will change to the more performance oriented E map. If the input signals change to a more gentle driving style then the adaptive controls will change back to a more economical XE map.

In the Sport program 'DS' with the selector lever in position M/S there is the basic S map (sport) and the performance oriented XS map (extreme sport). If an extremely dynamic driving style is called for, the system will change from the S map to the XS map.

The adaptive systems responds to driving uphill (or towing a trailer), driving downhill, braking/deceleration and winter driving (i.e. info from the DSC). Otherwise the adaptive systems respond to the type of driver using the car and assesses the rate of throttle movement, cornering approach (i.e. wheel speed sensors, yaw rate, road speed), constant-speed travel values and how aggressively you are decelerating.

The adaptation process is restarted each time the car pulls away from a standstill. Adaptation works by comparing the inputs with a set of threshold values that have been constructed from the moment your car was driven following it's last reset (usually at the factory).

Sport automatic gearbox
The concept of a sporting automatic gearbox was, until recently, something of an oxymoron. BMW’s Steptronic gearbox was introduced as an option in the BMW 750i/iL in September 1995 and offered greater driver interaction than the previous automatic gearbox. Sports-minded owners had the option of letting the gearbox self-select around town, but manually select the gear when driving more spiritedly.


BMW’s new Sport automatic gearbox in the Z4 3.0si Coupé takes BMW automatic gearboxes to a new level and offers drivers the choice of three selection modes; automatic, manual selection using the gear lever (Steptronic) and now, manual selection using steering wheel-mounted paddles. A Sport automatic-equipped car also changes gear in half the time of a conventional auto gearbox, delivers a 40 per cent improvement in the gearbox response time and even blips the throttle on down-changes for a sporting sound track and smoother transition between gears.
To change the selection mode, the driver simply changes the position of the gear lever or pulls one of the paddles. The normal automatic mode is re-activated if the driver doesn’t touch the paddles or the selector lever for over 12 seconds.
This paddle-shift system is completely different to the well-known BMW SMG systems, which are based on a manual gearbox.