[Tdavid1]

BMW F30 TRANSMISSION

Hello I have a 2013 BMW 328i Xdrive Recently my transmission feels very jerky and having a hard time shift out of 1st and sometimes will kick real hard, with a drive train malf. Happened after I drove in the snow. Anyone have this problem and/or a solution? thanks

UPDATE: now my car won't even make it down the street without drive train malf coming on and putting me in limp mode.

CODES:
420441: Gear ratio monitoring in fixed gear, Clutch E, disrupted.

4204A1:Gear ratio monitoring in fixed gear, clutches B and E, disrupted.

420311: Gear ratio monitoring, gear shift 1 to X not plausible.

[VipinLJ]

Sounds like a mechatronics failure?

[Pruzina]

Have you resolved it? I have the exact 3 codes.

[Slick_FThirty]

Has your fluid been leaking?

[Pruzina]

So I Found out that the previous owner was driving the car with low fluid in transmission which most likely damaged the transmission. Actually not most likely it did damaged the transmission.
It was missing almost 2 quarts

[Slick_FThirty]

Originally Posted by Pruzina

So I Found out that the previous owner was driving the car with low fluid in transmission which most likely damaged the transmission. Actually not most likely it did damaged the transmission.
It was missing almost 2 quarts

Sorry to hear that.

2 quarts low sounds like something was leaking, probably the mechatronics sleeve. The mechatronics sleeve is plastic and tends to crack and leak at higher mileage.

[auburnf30x]

Originally Posted by Slick_FThirty

Sorry to hear that.

2 quarts low sounds like something was leaking, probably the mechatronics sleeve. The mechatronics sleeve is plastic and tends to crack and leak at higher mileage.

Either that, or the last guy who owned the car may have done (or had done) a transmission service and didn’t follow the fill procedure properly.

[Pruzina]

I was thinking the same. But the sleeve was super dry no oil in the connector either. I can see some fluid all over the bottom of the plastic pan but nothing really alarming.
I think it was leaking around the coolant lines.
Either ways the transmission is dead.
I added oil with no improvement what so ever.
And I can clearly hear grinding noise coming from the trans. Seems like it's coming from the torque converter.
I'll drain the fluid and drop the pan but I'm not expecting to find anything interesting.

Hope the trans swap is one man job

[Slick_FThirty]

Originally Posted by auburnf30x

Either that, or the last guy who owned the car may have done (or had done) a transmission service and didn't follow the fill procedure properly.

Indeed. I'd be curious to hear whether a shop did it, or owner did a sketchy job.

But if you only do a drain and fill and don't power on the car for the final fill (which would be incorrect), it would still only be a litre low.

The maintenance and how it was done is one of the primary things that I worry about with second hand cars….

[Pruzina]

Originally Posted by auburnf30x

Either that, or the last guy who owned the car may have done (or had done) a transmission service and didn’t follow the fill procedure properly.

That's exactly what I thought.
But given the fact that the pan is ZF and if I'm not mistaken even zf replacement pan doesn't have zf branding (not sure about that) and that the filler plug was that crazy tight that I was really scared that I'll f**k it up. I don't think that trans have ever been serviced.

[Pruzina]

Originally Posted by Slick_FThirty

Indeed. I'd be curious to hear whether a shop did it, or owner did a sketchy job.

But if you only do a drain and fill and don't power on the car for the final fill (which would be incorrect), it would still only be a litre low.

The maintenance and how it was done is one of the primary things that I worry about with second hand cars….

Exactly. I just did fluid change on my gf's 335i with 6hp and it took about quart after warming to the temp. 2 quarts seems too crazy. But anything is possible people are crazy. They can't even follow DYI videos on YouTube

[auburnf30x]

Mine took a little over two liters for the final fill (after three for the first) but since it’s the first time I’ve done that on a ZF, I can’t really say if that’s a typical result or not. My replacement pan does have the ZF stamp on it, but doesn’t have the green lifetime fluid sticker. Sticker would probably tell you if someone has been in there or not.

[Pruzina]

Originally Posted by auburnf30x

Mine took a little over two liters for the final fill (after three for the first) but since it’s the first time I’ve done that on a ZF, I can’t really say if that’s a typical result or not. My replacement pan does have the ZF stamp on it, but doesn’t have the green lifetime fluid sticker. Sticker would probably tell you if someone has been in there or not.

It does have the green sticker. even the filler plug had no wear like nobody ever loosen it

[auburnf30x]

Originally Posted by Pruzina

It does have the green sticker. even the filler plug had no wear like nobody ever loosen it

Most likely still on the factory fill, then.

[Pruzina]

Little update.
So I removed the old transmission and clearly it was out of the car before and someone replaced torque converter.

Anyway I install "new" transmission and the car won't shift out of park.
Did some research and found out that the mechatronic unit is "married" with ecu for that reason it won't shift.

Okay no problem let's swap the mechatronic unit. I opened up both transmissions to swap the mechatronic just to find out that the "new" one has some extra cylinder inside. Did research again and learn that the car which the "new" tranny came from had start stop feature and that's what is the cylinder for.

Now I'm scared shitless if it's going to work. Can't find anything online if it will work.

If someone has some knowledge about that I would really appreciate it
Thanks

[Slick_FThirty]

Originally Posted by Pruzina

Little update.
So I removed the old transmission and clearly it was out of the car before and someone replaced torque converter.

Anyway I install "new" transmission and the car won't shift out of park.
Did some research and found out that the mechatronic unit is "married" with ecu for that reason it won't shift.

Okay no problem let's swap the mechatronic unit. I opened up both transmissions to swap the mechatronic just to find out that the "new" one has some extra cylinder inside. Did research again and learn that the car which the "new" tranny came from had start stop feature and that's what is the cylinder for.

Now I'm scared shitless if it's going to work. Can't find anything online if it will work.

If someone has some knowledge about that I would really appreciate it
Thanks

Wouldn't that just be a signal? I'm sure the ECUs etc. are the same between auto start stop and not. There is some circuit that could be as simple as a wire that would be controlling that.

Now, if the coding for ASS is there in the ECU and is off and the circuitry is there, then it would be off. The additional hardware would be redundant and would just stay off.

If the connectors are the same and the coding value is there as off, explicitly off, and not just unknown, then it might be fine.

Write ZF an email or reach out to a transmission specialist but even they might not know and just recommend having identical units.

[Pruzina]

Oh and I completely forgot to mention that when I installed the "new' transmission and just casually removed the filling bolt absolutely not prepared to catch any fluid, fluid started to poor out like crazy. Complete disaster on my floor ended up catching over 3 quarts of fluid. Which means that tranny was big time overfilled. At this point who knows if this one is not screwed too.

[Pruzina]

For illustration
1st and 2nd picture are the "new" installed in the car where you can see the start stop cylinder plus the harness connected in to the cylinder

3rd and 4th old tranny without cylinder and obviously no harness.

So if I transfer my old mechatronic over to "new" I will not have the harness which goes in to the cylinder. The question is if the ecu is going to have problem with that or not.

Seems like the only way how to find out is to try.

[Slick_FThirty]

Originally Posted by Pruzina

Oh and I completely forgot to mention that when I installed the "new' transmission and just casually removed the filling bolt absolutely not prepared to catch any fluid, fluid started to poor out like crazy. Complete disaster on my floor ended up catching over 3 quarts of fluid. Which means that tranny was big time overfilled. At this point who knows if this one is not screwed too.

Well it will appear overfilled, because when the engine is not running, the fluid comes out of the torque converter.

This is the reason why the engine must be running during the fill. After you top up the fluid and turn on the engine, it needs another litre.

That doesn't conclusively say whether or not it was overfilled. But what you experienced could be normal.

[Slick_FThirty]

Originally Posted by Pruzina

For illustration
1st and 2nd picture are the "new" installed in the car where you can see the start stop cylinder plus the harness connected in to the cylinder

3rd and 4th old tranny without cylinder and obviously no harness.

So if I transfer my old mechatronic over to "new" I will not have the harness which goes in to the cylinder. The question is if the ecu is going to have problem with that or not.

Seems like the only way how to find out is to try.

That's strange. I haven't seen the ZF8HP without that. Are you sure it isn't missing from the old one?

Potentially, you could connect the mechatronics unit only, and keep the transmission there without doing all the work. Run a diagnostics with it and see if the ECU can communicate with it.

ISTA+ would allow you to do that.

[Pruzina]

Originally Posted by Slick_FThirty

Well it will appear overfilled, because when the engine is not running, the fluid comes out of the torque converter.

This is the reason why the engine must be running during the fill. After you top up the fluid and turn on the engine, it needs another litre.

That doesn't conclusively say whether or not it was overfilled. But what you experienced could be normal.

Good point. Hopefully you are right. Not sure if the torque converter holds over 3 quarts.

[Pruzina]

Originally Posted by Slick_FThirty

That's strange. I haven't seen the ZF8HP without that. Are you sure it isn't missing from the old one?

Potentially, you could connect the mechatronics unit only, and keep the transmission there without doing all the work. Run a diagnostics with it and see if the ECU can communicate with it.

ISTA+ would allow you to do that.

No it's not missing not all cars with zf8hp have start stop so no need for the cylinder. Also the new one has extra hole where the cylinder is fitted mine doesn't have the hole. For that reason I have to leave the cylinder in place even if it's not going to be in use and connected to basically plug the hole. But I don't know if that is not going to make problems with fluid pressure inside the transmission.

Thats exactly what I'm going to do right now. I'll report back. The question is if the diagnostic data will be accurate with engine off. With no fluid pressure data.
fingers crossed. I really don't wanna pull the tranny out again.