[b-man]

I have a weird problem going on with my auto tranny. I mentioned it to the dealer and the response was "The transmission is just thinking, it's normal" I got so upset at the response that I didn't know what to say...

Here is what's going on, and it only happens when it's cold out and before the car/fluids warm up. I'm starting to drive, the car is in D, I'm not flooring it, giving it just enough gas so it'll shift around 2500rpm or so, it'll shift to 2nd, and then it won't shift to 3rd until like 4500rpm, and this is without giving it more gas, I have not moved my foot at all, then it'll shift to 3rd, then for like a second or two there's no acceleration and rpm is down to like 1k, and then it'll continue accelerating like nothing happened.

Has anyone had an issue like this?

[ThatRWD]

Are you under any kind of BMW provided warranty? I feel like Stealers don't like to warrant work under BMW warranties, plus some stealers are just horrid they can only read codes, I'm surprised they don't say "well there aren't any code that says you need new tires."

In the warm up period it's normal for it to delay shifts/slow shifting/higher rpm shifts. I've had that happen before but I believe that was when I was pushing more gas then I normally do, I normally put enough gas so it shifts around 1800-2200. I'll try and replicate it again on my way home today or tomorrow morning, but I believe it only happens on cold days as well.

The following doesn't answer exactly your question, nor fix your problem. But, 1-2 shifts are generally low RPM shifts compared to the 2-3 shift. So when you say that applying the same amount of gas 1-2 shifts earlier than 2-3, could be normal.

[m@rco]

I drive a manual and haven't had this experience... But, for what it is worth, I know about a gearbox of a 528i that, after 150,000 miles started to swift 'rougher'. What you describe is absolutely not normal. "The transmission is thinking." Ha ha, give me a break. Yes, when the engine is cold, the car switches gears at 2,200rpm, and not at 1,800rpm if you accelerate slowly. But that is about as far as it goes.

Your problem could have to do with small impurities in the gearbox oil, see picture of labyrinth in link below (sorry Dutch website, but pictures (and google translate) tell a 1000 words), where the oil doesn't flow smoothly through all channels. Impurities may block/hinder/cause hiccups in the shifting pattern. I would first check the codes. Then consider a fluid change. You may also refurbish your gearbox. But I would try to find a specific, BMW-experienced, garage for that, and avoid the dealership because it is expensive... How many miles do you have on your car?

http://automaat-reinigen-spoelen-olie-verversen.nl/

I presume you don't have a tail hook and pull 3,000 lb caravans over the Alps - like many Europeans do. Which is totally fine, by the way, but causes a bit more wear on the transmission - so I've been told.

[kiel_dafo_kenyg_as]

When it's cold outside shifting is delayed for a faster engine warm up (and less emissions). I haven't driven the 6 speed in winter yet but in the first minutes after cold start my e38 never shifted under 3500 rpm

[b-man]

I have 57k on it, and still have maintenance and warranty from bmw.

I understand the late shift when it's cold, but this didn't seem like that.

Went to the dealer for a brake job (free under maintenance! yay!), they said they upgraded some software that fixes an issue with cold start acceleration. Haven't had it happen since then!

[GB-335xiCoupe]

Alpina trans flash might help, and also reset the AT adaptations...

[b-man]

There's no alpina trans flash for my car. 328xi with gm tranny...

[m@rco]

Originally Posted by whiteblue

When it's cold outside shifting is delayed for a faster engine warm up (and less emissions). I haven't driven the 6 speed in winter yet but in the first minutes after cold start my e38 never shifted under 3500 rpm

Sorry to ask, but who taught you that?!? I'm sorry to say, but what you say is totally wrong...

1) Not for a faster warm up, only to leave the engine run a little bit smoother. At cold temperatures, fuels condensate inside the cylinder and don't combust well. But running slightly higher rpms, the engine has less tendency to stutter or stall... The 'computer' of the transmission is programmed such that it will only shift slightly later, however, still as soon as possible. A fast warm up is bad: metals don't heat up at the same speed and there is no way to increase it. It only results in more wear because the oil is not hot. Why wouldn't car manufactures otherwise 'program' the computer to shift late?

2) Shifting your MT below 3500rpm when cold is about the worst thing you can do to your engine! Your oil is only at operating temperature after driving about 10-12 miles. Period. Only then, the oil provides the lubrication that is necessary. Especially when running at high rpms.... Shift at 2,200 rpms in all gears and take it easy for the first 10-12 miles. Only after then, you may step on it. When you go to the gym or when you go run in the park, just after waking up, do you also start with lifting the heaviest loads and pulling a sprint?

[kiel_dafo_kenyg_as]

European cars have the "Schaltdrehzahlanhebung" (shifting point uplift) called feature since the early 90's when emission standard Euro1 was introduced. You may know a cold catalytic converter doesn't work. The fast heat up routine serves for heating up the catalytic converters and is an indispensable part for matching E1 specs.

Meeting specs has priority and car companies give a fork about what's good or not good for extendet engine life.