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OrgBimmerDude
09-24-2012, 02:45 PM
Hello Everyone,

Vehicle type is a 2004 745li bmw v-8 6 speed transmission. when the car is in 5th gear the car hiccups like it wants to up shift but then does not. it cause the car it jerk every 3 to 5 seconds when in 5th gear. when the car is in any other gear in does not do this. i have had a transmission fluid completely changed out. in which the fluid smelled burnt and looked brown in color. bmw says that it is a life time fluid (it is not). when the car is accelerating through 5th gear it does not do the problem either. there is something clearly wrong which the transmission. i have taking the car to two independent transmission shops and they have no idea. i have learned that the car will stay in 6th gear at 45 mph and normally cruise in the city in 4th gear at lower speeds and avoid 5th gear with the use of the manual shifts on the steering wheel.

Anyone know what this could be???? It only happens once in awhile. Its just annoying at times.

Thanks guys...

Catanzaro
09-25-2012, 08:48 AM
Have the fluid pan filter gasket changed. Put proper fluid. Then have dealer check EGS software calibration. Read my posts. A lot if information. If fluid was burnt possible damage but I doubt it. Low fluid or too much or wrong fluid makes tranny shift weird. Keep us posted.

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SFbay
09-25-2012, 09:10 AM
First replace mechatronic adapter and sleeve. This is a mist after 80k

Catanzaro
09-25-2012, 11:13 AM
Are you getting any harsh downshifts or on the way up?

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OrgBimmerDude
09-26-2012, 08:17 AM
Hey, thanks for all the information... Mechtronics and sleeve have been changed and at the same time, filter and pan and fluid have been changed at the dealer.. They actually recommended it to all be done in one shot... So I assume the right fluid is in because all the work is under warranty by dealer... I took it to the dealer and it doesn't do it to them, they did flash all my systems, everything has been updated, so basically all new software and whatever else. So far, it hasn't done it in the last month, but there has been a few days it has. Very strange, I'm crossing my fingers because the SA did say to give it time for the car to adapt to the new updates... This is all I have for you... What do you guys think?

OrgBimmerDude
09-26-2012, 08:24 AM
Are you getting any harsh downshifts or on the way up?

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No harsh downshifts, everything is smooth as silk... Shifting is fine, just once in a while I get the hiccup, annoying, but at least its not and daily thing..

Blackmax100
12-17-2012, 04:47 AM
HI
Did you ever get this fixed.
Seams to be happening with a few 745's including mine.
But I have not found a posted solution.

SFbay
12-17-2012, 09:00 AM
No harsh downshifts, everything is smooth as silk... Shifting is fine, just once in a while I get the hiccup, annoying, but at least its not and daily thing..

At this point I can tell that tranny is going out... You need to rebuild it
Probably bc you've been driving with bad leaky mechatronik adapter for a while which caused low oil pressure and starvation on low rpm;(

csmeance
12-17-2012, 09:52 AM
this is the transmission having to keep on locking and unlocking to maintain the current speed. To put it in easier words, it's like driving a stick in a gear that's too high.

I'd look into some sort of other issue like having the wrong size tires, having low engine output, etc.