Stupid question: how many gears does my car have?

[Jay 535i]

A 1990 535i with an auto tranny. I know BMW was among the first to offer a 5-speed auto. Do I have one?

[tnt525i]

A 1990 535i with an auto tranny. I know BMW was among the first to offer a 5-speed auto. Do I have one?
i think you have the 4 speed auto, i think its calles the 4hp22 not sure

[Bill R.]

its shifting one more time when the converter locks up... but its not..






A 1990 535i with an auto tranny. I know BMW was among the first to offer a 5-speed auto. Do I have one?

[Jay 535i]

its shifting one more time when the converter locks up... but its not..

Thanks. The converter lock-up is what made me decide I couldn't figure this out just by counting ;)

My father had a similar 740il a while back, and it was a 5-speed auto IIRC, so I wondered if my car had the same thing. Guess not.

Thanks.

[Kalevera]

The E32 740 uses ZF's 5hp-30, which is a 5 speed trans.

best, whit

[Zeuk in Oz]

You have a 4 speed with a lock up converter so some people think that its shifting one more time when the converter locks up... but its not..
My F250 7.3 litre turbo diesel has a 3 speed auto box with lock up torque converter. Ford calls it overdrive ! LOL

[Jay 535i]

The E32 740 uses ZF's 5hp-30, which is a 5 speed trans.

best, whit

That 'splains it. Thanks.

[Kakaire]

My F250 7.3 litre turbo diesel has a 3 speed auto box with lock up torque converter. Ford calls it overdrive ! LOL

thx

[Jay 535i]

thx

Your torque converter is like a big piece of goo between the engine and the driven wheels. When you put your foot down to make more power, the power is trasmitted through the goo, giving an 'elastic band' feeling -- like your right foot is not directly connected to the driven wheels. Which it isn't. It is in a manual car, though, because a clutch (hopefully) doesn't slip the way a torque converter does.

The torque converter has to behave this way to accomodate slow speed driving and in-gear idling, given that you don't have a clutch.

At higher speeds, to increase economy and throttle response, the torque converter can lock up, which means that it stops being goo and starts being a solid mechanical connection between engine and wheels. When the torque converter is locked up, throttle respose is as good as in a manual car.

My post was prompted by my desire for that manual-car level of throttle response through medium-speed corners. I hate that there's a delay and a gooifying effect of my right foot's movements by the time they get to the driven wheels. A locked up converter would make it much easier for us auto guys to balance the car through corners with the accelerator.

Hope that explains things.

[mzarifkar]

Your torque converter is like a big piece of goo between the engine and the driven wheels. When you put your foot down to make more power, the power is trasmitted through the goo, giving an 'elastic band' feeling -- like your right foot is not directly connected to the driven wheels. Which it isn't. It is in a manual car, though, because a clutch (hopefully) doesn't slip the way a torque converter does.

The torque converter has to behave this way to accomodate slow speed driving and in-gear idling, given that you don't have a clutch.

At higher speeds, to increase economy and throttle response, the torque converter can lock up, which means that it stops being goo and starts being a solid mechanical connection between engine and wheels. When the torque converter is locked up, throttle respose is as good as in a manual car.

My post was prompted by my desire for that manual-car level of throttle response through medium-speed corners. I hate that there's a delay and a gooifying effect of my right foot's movements by the time they get to the driven wheels. A locked up converter would make it much easier for us auto guys to balance the car through corners with the accelerator.

Hope that explains things.

I noticed if im (in my 95 525i) in the 1 or 2 position, in A mode, the car is much more responsive, in comparison to a start from zero in s3 mode. does this have to do with the goo locking up?

[Jay 535i]

I noticed if im (in my 95 525i) in the 1 or 2 position, in A mode, the car is much more responsive, in comparison to a start from zero in s3 mode. does this have to do with the goo locking up?

No, I think that's because, by default, your car always pulls away from a stop in second gear. You can force a first gear start by putting the lever in the 1 position.

I think, anyway. Someone more knowledgeable can probably explain better.

In 'A' mode, the torque converter will only lock up in 4th at high-ish speeds. In Sport mode, it will sometimes lock up in 3rd. It will never lock up in 1st or 2nd in our car, although other cars differ. For example, in the new Bently Continental GT, the torque converter locks above 1600RPM in every gear, giving manual-like throttle response almost all the time. Of course, that car's mammoth torque is a big part of why Bentley can get away with that without poor low-speed driveability.

[Nick.Hay]

I was somewhat confused about this too. So the converter 'lock-up' is when you feel the car drop into 'top' gear when cruising??

He He HE!!!! In that case, if I keep the the thing nailed on the highway, my '90 535i locks the converter at about 210km/h!! :D :D

Whilst on the subject. How does the 'sport' mode affect the gearbox??
Ive noticed that this mode leaves a little to be desired with its programmed ratios and things.

[Jay 535i]

I was somewhat confused about this too. So the converter 'lock-up' is when you feel the car drop into 'top' gear when cruising??

Not necessarily. The torque converter might already be locked by the time you get to top. From the driver's seat, the lock-up does feel like a shift, but the revs don't drop quite so much.


He He HE!!!! In that case, if I keep the the thing nailed on the highway, my '90 535i locks the converter at about 210km/h!! :D :D

That's probably the tranny shifting into top. Chances are your torque converter is already locked by then, although it slips during the shift. I don't really know, though, under exactly which circumstances the converter is locked or not locked.


Whilst on the subject. How does the 'sport' mode affect the gearbox?? Ive noticed that this mode leaves a little to be desired with its programmed ratios and things.

Sport locks out overdrive, just as if you'd moved the selector into 3. It also engages a new shift program which:

1) is more eager to initiate downshifts
2) will hold gears longer when accelerating (i.e. no short-shifting -- screw economy)
3) is less eager to upshift when you reduce the throttle (to maintain balance through corners and add a bit of engine braking when decelerating)
4) maybe improves throttle response -- someone correct me on this

It may do other things too. Maybe someone else can enlighten us. I also find it less-than-perfect, but still useful.

[Kakaire]

Jaylebo, thx for the "Lock up Convert" precise explanation. What can we do without you guyz?

[pundit]

I was somewhat confused about this too. So the converter 'lock-up' is when you feel the car drop into 'top' gear when cruising??
On a flat road with gradual acceleration you should feel the convertor lock at about 85km/h. It almost feels like 'half' a gear change.



He He HE!!!! In that case, if I keep the the thing nailed on the highway, my '90 535i locks the converter at about 210km/h!! :D :D
Refer to above.



Whilst on the subject. How does the 'sport' mode affect the gearbox??
Ive noticed that this mode leaves a little to be desired with its programmed ratios and things.
Sport mode basically changes the shift pattern by allowing higher RPM's before the auto shifts up to the next gear.

[Dan in NZ]

Mmmmm. I do a lot of highway driving, and always feel the torque converter lock up at about 85km/h with light accelerator pressure. Only happens in top gear, at 85 or over, with lightish pressure on the gas. If I'm having a heavy foot day, it will stay unlocked until I ease off the gas, usually around 100 (speed limit). Also interesting to note, the torque converter doesn't lock up until the engine/trans is warm, I drive straight on to the highway with the car cold and notice this every now and then.

You can tell if the torque converter is locked by tapping on and off the gas. If it's unlocked, the rpm's will fluctuate with accelerator pressure. When it's locked, the rpms will remain exactly proportional to road speed, just like a manual.

I don't think it will lock-up before you get to top gear, because when it did shift to top it would be a very harsh shift without the torque converter to smooth it out. Bentleys do lock-up in lower gears, but I'm assuming they only lock if it intends to keep it in that gear, and unlocks it when it shifts.

[Jay 535i]

You can tell if the torque converter is locked by tapping on and off the gas. If it's unlocked, the rpm's will fluctuate with accelerator pressure. When it's locked, the rpms will remain exactly proportional to road speed, just like a manual.

Yup, and that's exactly what I hate about auto cars. It's bad enough that they do my shifting for me, but what really gets me is the disconnect between the accelerator and the wheels that makes it impossible to balance the car accurately with the throttle.


I don't think it will lock-up before you get to top gear, because when it did shift to top it would be a very harsh shift without the torque converter to smooth it out. Bentleys do lock-up in lower gears, but I'm assuming they only lock if it intends to keep it in that gear, and unlocks it when it shifts.

According to the owner's manual, Sport mode will allow the converter to lock in 3rd as well as top. It would always slip during a shift, though.