Auto box noise, please help.....

[ben wilamowski]

1994 BMW 540i V8 Auto, sealed for life 5hp box.

Mileage 96,000 miles FBMWSH

OK Guys, I would be really grateful if someone could help with this:

BMW have changed the transmission oil and strainer for me and the following things happened:

The change is now lovely and smooth where before it was really harsh on occassions and did not seem to change correctly so I am pleased and I feel that the box is now changing gear properly.

However I still have a really weird fault:

The main issue is that I get a weird screech type / whirring noise when I first pull away in the morning and she trys to hold a higher gear than she should.

This does not happen at all if I leave the car to idle for 5mins before I drive off and the problem dissapears within about 3 mins of driving along the road.

Is it possible that the oil pump on my gearbox has had enough and simply needs replacing?

Just in case any of you where unaware everything under the bonnet has now been replaced that could possibly generate any weird noises so this noise has to be as a result of the gearbox itself or the gearbox oil cooler lines / cooler.

If anyone has any idea what this could be or things I should check I would be really glad to hear from you.

[Dick Schneiders]

The screech noise seems strange, but the rest of it is the way all of the BMW auto trannys I have ever driven act. The auto trannys will stay in a lower gear, and keep the rpm's up, longer when the engine/tranny are not yet warmed up. It is exactly as you describe, it only takes a few minutes of driving before the system warms up and the shift points then become normal.

This is a normal situation, if I understand what you are asking. However, the noise is not something I have ever experienced.

1994 BMW 540i V8 Auto, sealed for life 5hp box.


However I still have a really weird fault:

The main issue is that I get a weird screech type / whirring noise when I first pull away in the morning and she trys to hold a higher gear than she should.

This does not happen at all if I leave the car to idle for 5mins before I drive off and the problem dissapears within about 3 mins of driving along the road.

.

[Bill R.]

filter on the car...

1994 BMW 540i V8 Auto, sealed for life 5hp box.

Mileage 96,000 miles FBMWSH

OK Guys, I would be really grateful if someone could help with this:

BMW have changed the transmission oil and strainer for me and the following things happened:

The change is now lovely and smooth where before it was really harsh on occassions and did not seem to change correctly so I am pleased and I feel that the box is now changing gear properly.

However I still have a really weird fault:

The main issue is that I get a weird screech type / whirring noise when I first pull away in the morning and she trys to hold a higher gear than she should.

This does not happen at all if I leave the car to idle for 5mins before I drive off and the problem dissapears within about 3 mins of driving along the road.

Is it possible that the oil pump on my gearbox has had enough and simply needs replacing?

Just in case any of you where unaware everything under the bonnet has now been replaced that could possibly generate any weird noises so this noise has to be as a result of the gearbox itself or the gearbox oil cooler lines / cooler.

If anyone has any idea what this could be or things I should check I would be really glad to hear from you.

[ben wilamowski]

Yes I think you understand what I'm trying to say the revs are higher than they should be when she is cold ie a "Lower" gear is selected, when she warms up then everything shifts as normal.

So at least I can forget about the shift behaviour now I just need to get to the bottom of the noise!

So difficult to describe but it is a kind of whirring noise which increases with engine speed from a standstill, extra strange is it only does it from stone cold when I first pull out of my drive in the morning, as soon as I am moving along the sound dissappears, it is only there when accelerating from a stanstill up to about 30 / 40 mph.

After about 3-5 mins the symptoms have totally gone.

I'm baffled!

The screech noise seems strange, but the rest of it is the way all of the BMW auto trannys I have ever driven act. The auto trannys will stay in a lower gear, and keep the rpm's up, longer when the engine/tranny are not yet warmed up. It is exactly as you describe, it only takes a few minutes of driving before the system warms up and the shift points then become normal.

This is a normal situation, if I understand what you are asking. However, the noise is not something I have ever experienced.

[ben wilamowski]

Thanks Bill,

That sounds like a definite possibilty.

Will get it checked out.

Cheers

Ben.

[tim]

Dear Ben,

I have considerable experience with this problem and I think I can tell you definitively what it is (Everything I know I learned from Kirt Koeller- dont forget his name because in the not too distant future, you are going to need him.)

The sound, variously described as a pencil sharpener or perhaps a boat winch is caused by cavitation on the torque converter blades. The direct cause of this is that your fluid level is too low, caused by filling up the tranny fluid at too high a temperature. Therefore it is taking too long for your torque converter to fill, exacerbated by the fact that it is possible that you have the too small o-ring on your filter pump lifter. This fluid is very sensitive to temperature changes. Once your tranny warms up, the fluid expands enough to stop the cavitation, so the problem disappears. The spec temp for filling is basically room temperature.

I will describe the procedure for proper fill:
1) get proper fluid (absolutely necessary)
2) obtain 17mm hex key (a hollow cheater bar will help)
3) raise car on jack stands(careful!!) or drive over a pit.
4) make sure car is level and cold.
5) start car and turn on lights and ac. run through the gears with your foot on the brake.
6) after 1 minute your fluid should be the right temp.
7) using the hex key, remove the main plug at the bottom of the tranny. Fluid should come out (hopefully, or else you were way too low)
8) Stick your pump tube up into the hole and fill with fluid until it overflows.
9) Close it up.

Hope it helps. If you are going to get a tranny guy to do it, change the o-ring on the filter lifter, cause that's problem too.

[Marshy]

Guys,

Thanks for those recommendations, sounds like exactly the noise I'm getting at the moment too. I don't like the idea that the fluid's too low - it's not long come back from the tranny shop. Sigh.

[tim]

marshy-

very few people, even those who "know," know how to do it right.

check this link and proceed as needed. It's got to be the easiest thing ever if you know how to do it.

edit- the link would help- http://www.peterschmid.com/zfinstall...ng%20procedure

tim

[infinity5]

How much did the dealer charge you for a fluid/filter change? or is going to the dealer even needed?

[ben wilamowski]

Tim,

Thank you very much for that, it's good to know I'm not the only one with this problem. When you tell the dealer and they almost think you're making it up it's a bit annoying to say the least!

Bill,

Do you by any chance have a document / bulletin number and any part numbers for the new oil filter / strainer and O ring.

I have just had a new strainer and O ring fitted by BMW and I want to check to see whether they used the new updated parts or not.

Cheers

Ben.