Z3: Auto tranny driving ?s

No problems, just operating questions -

The car is designed to default to E (Economy). The owner's manual says for M (manual) "This program is for driving conditions under which the selected gear is to be retained."

I don't understand the difference between the above quote and simply downshifting while in E. For instance, I leave my house, the car is in E, and I immediately head down a hill. I shift into 2nd gear to avoid overusing the brakes; the car stays in 2nd until I shift out of it.

So my question is, what's the practical purpose of M? Am I doing anything harmful to the car by using the default of E and running the car through the different gears when terrain, city driving, or mood calls for it?

Thanks. Jim

You have 5 forward gears to select from when in (M) manual mode. On your gearshift selector your + and - determines whether or not you wish to upshift or downshift. In the manual mode you also are in the sport mode (performance). If you keep your selector in the auto select mode and push your gear selector to the left you will be in the auto sport mode and your car will automatically shift at higher performance levels than in the non sport mode. The advantage of the Steptronic Transmission is the ability to manually shift your car without the use of the clutch. It is not as precise as having a clutch because there is a bit of a lag, but it's pretty darn close. You also cannot blip your accelerator when you are downshifting with the Steptronic. The new Dual Clutch Transmissions (DCT) in the Z4's are claimed to be better than a standard transmission performance wise and are the automatics of the future and found in many high performance cars besides BMW.

The OP is driving a 2000 MY Z3. It's not the same Steptronic setup as in the 2001-2002 models. It's an earlier version and works differently.

I have the 2000. I'm all ears...

The thing is that if you select any lower gear while in the A mode, you will get all gears up to that one ie: if it's in 2, it will shift from a stop from 1 into 2, then 2 into 1 as you stop. it will still be automatic, but only shift up and down from the selected gear automatically. If you select a lower gear while in the M mode it will select and hold that gear, therefore if im driving in "3" in the M mode, it will stay in 3 even when I come to a stop... when I press the gas to start again, it will be dog slow because it's still holding the 3rd gear. I don't mess with the M mode in my car, nor do I bother shifting into other gears. BTW you will not be saving much brake pad so just drive your car in D.

Al.

FYI, your car is a Z3 2.3 (M52b25TU) not 2.5 (M54)

Al,

I believe you because you sound so confident. However,
1. How can it NOT affect brake pad wear if you're not applying brakes when relying on the tranny? and
2. How did you know my car was a 2.3 and not a 2.5? Besides which, I thought that the engine was a 2.5 even though the model designation was 2.3.

Originally Posted by Belgirb

Al,

I believe you because you sound so confident. However,
1. How can it NOT affect brake pad wear if you're not applying brakes when relying on the tranny? and
2. How did you know my car was a 2.3 and not a 2.5? Besides which, I thought that the engine was a 2.5 even though the model designation was 2.3.

Well, ok it will affect brakepad wear, but the difference is so minimal, unless you are constantly riding your brakes. When you drive, learn how to feather the pedals (brake/accel) to control your speed.

I know because I also have a 2000, and thats the only engine besides the 2.8 and the ///M that was available.

I'm very familiar with the M52B25 and M52B25TU as I've owned both. I make sure to call my Z3 a 2.3 because people just use engine size, instead of model to point out, when there clearly is a difference between an M52 and M54.