[Smurfzilla]

Subject: 2008 E90 Sedan w/100k + miles on the clock. Daily driven with MHD Stage 2 flashed. Car is not beat on daily and normally is driven spiritedly every once in a while (not lately with the trans issues).

ok guys so my transmission has been doing something weird and it started happening shortly after i flashed the AlpinaMod on the car and it seems to slowly be getting worse.

Symptoms: Accelerating at more then 60% throttle results in a quick upshift from 4th gear to 5th and back down again. If I stay in the throttle it will throw a trans code if I get out of it briefly and get back into it, it will accelerate ok. It does this about 90% of the time from 4th to 5th, about 10% of the time from 5th to 6th and about 5% of the time from 3rd to 4th (Thats a new development).

Things tried to remedy:
- Changed fluid and replaced mechatronic sleeve and pan. Seemed to alleviate it a bit but for the most part same issues.

- disabled kickback in MHDFLasher. Seemed to help a bit but for the most part no change.

The most obvious part is I should flash the transmission back to stock but I'm still learning my way around the platform and I dont want to flash the wrong thing (Thinking about having an indy help me here). Assuming that flashing it back to stock doesnt work I have been thinking of a few different ways to get this resolved.

1) Just have a indy pull the transmission out, send it to a 6HP21 specialist to go over it and rebuild it. Its my primary vehicle although I have others to drive I dont really want to do this if I can avoid it.

2) Buy a cheap used 6HP21 and send it off to a ZF specialist and drive until the transmission is back.

or

3) Buy a good used ZF (if I can find one of those) and swap it into my car then send mine out to a ZF specialist for rebuild and hold on to it until I need to replace my current one.

My friend in Atlanta is a BMW specialist and he swears by these auto trans (my first i normally drive stick). He thinks this a anomaly. Trying to think of the most cost effective thing to do while still being able to drive. I actually just enjoy driving this thing.

Thanks for any info or wisdom anyone can impart on me (Including a ZF transmission specialist) or any thing else i haven't tried troubleshooting wise based off my description.

[STR8-6IX]

Originally Posted by Smurfzilla

Subject: 2008 E90 Sedan w/100k + miles on the clock. Daily driven with MHD Stage 2 flashed. Car is not beat on daily and normally is driven spiritedly every once in a while (not lately with the trans issues).

ok guys so my transmission has been doing something weird and it started happening shortly after i flashed the AlpinaMod on the car and it seems to slowly be getting worse.

Symptoms: Accelerating at more then 60% throttle results in a quick upshift from 4th gear to 5th and back down again. If I stay in the throttle it will throw a trans code if I get out of it briefly and get back into it, it will accelerate ok. It does this about 90% of the time from 4th to 5th, about 10% of the time from 5th to 6th and about 5% of the time from 3rd to 4th (Thats a new development).

Things tried to remedy:
- Changed fluid and replaced mechatronic sleeve and pan. Seemed to alleviate it a bit but for the most part same issues.

- disabled kickback in MHDFLasher. Seemed to help a bit but for the most part no change.

The most obvious part is I should flash the transmission back to stock but I'm still learning my way around the platform and I dont want to flash the wrong thing (Thinking about having an indy help me here). Assuming that flashing it back to stock doesnt work I have been thinking of a few different ways to get this resolved.

1) Just have a indy pull the transmission out, send it to a 6HP21 specialist to go over it and rebuild it. Its my primary vehicle although I have others to drive I dont really want to do this if I can avoid it.

2) Buy a cheap used 6HP21 and send it off to a ZF specialist and drive until the transmission is back.

or

3) Buy a good used ZF (if I can find one of those) and swap it into my car then send mine out to a ZF specialist for rebuild and hold on to it until I need to replace my current one.

My friend in Atlanta is a BMW specialist and he swears by these auto trans (my first i normally drive stick). He thinks this a anomaly. Trying to think of the most cost effective thing to do while still being able to drive. I actually just enjoy driving this thing.

Thanks for any info or wisdom anyone can impart on me (Including a ZF transmission specialist) or any thing else i haven't tried troubleshooting wise based off my description.

did you also replace the pan filter?

it is very likely that you need new transmission solenoids. you should have replaced those when servicing the fluid.

also, a transmission adaptation reset should help, but it will only fix your issue temporarily until you get those solenoids replaced.

[Smurfzilla]

yes replaced filter (I thought it was built in to the pan)? Should I just replace all solenoids?

[shadow191]

Does it slip while in gear? Or just the weird shifting? You may be able to get away with replacing the valve body. Not sure about the costs of used ones. Or you can buy a solenoid kit but by the time you factor in labor, it may be better off with just a used valve body.

Swapping out the entire transmission is probably overkill unless you just get a great deal and are experiencing other issues.

I doubt resetting the adaptations will do anything at all. If you're throwing codes and it's shifting strangely you're beyond that. Personally resetting adaptations seems more placebo than anything. I tried it and there wasn't any difference but some people swear it works.

[JC888]

I had this happened to me a few years back which sounds like what you are experiencing. It was due to the clutch pack slipping and not holding.

http://www.e90post.com/forums/showth...=836218&page=2


I ended it up replacing the tranny and haven't had any problems since.

[STR8-6IX]

Originally Posted by Smurfzilla

yes replaced filter (I thought it was built in to the pan)? Should I just replace all solenoids?

yes, the filter is integrated into the pan.

may as well replace all 6 solenoids. you will get better shifting throughout the gears because your current ones are aging.

[Smurfzilla]

Originally Posted by shadow191

Does it slip while in gear? Or just the weird shifting? You may be able to get away with replacing the valve body. Not sure about the costs of used ones. Or you can buy a solenoid kit but by the time you factor in labor, it may be better off with just a used valve body.

Swapping out the entire transmission is probably overkill unless you just get a great deal and are experiencing other issues.

I doubt resetting the adaptations will do anything at all. If you're throwing codes and it's shifting strangely you're beyond that. Personally resetting adaptations seems more placebo than anything. I tried it and there wasn't any difference but some people swear it works.

It slips in gear. Its all in throttle input. it won't slip unless I;m giving it more throttle then normal. Also I say slip but to me a slip would be acceleration with no movement (aka gear slip) it upshifts quickly and then goes back to the original gear. I've never seen anything about it.

[Smurfzilla]

Originally Posted by STR8-6IX

yes, the filter is integrated into the pan.

may as well replace all 6 solenoids. you will get better shifting throughout the gears because your current ones are aging.

Yeah if I decide to keep plugging away at this transmission I may try this next. Found a good price for them on FCP Euro

[Smurfzilla]

Originally Posted by jcy335xi

I had this happened to me a few years back which sounds like what you are experiencing. It was due to the clutch pack slipping and not holding.

http://www.e90post.com/forums/showth...=836218&page=2


I ended it up replacing the tranny and haven't had any problems since.

Reading your thread now

[STR8-6IX]

Originally Posted by Smurfzilla

Yeah if I decide to keep plugging away at this transmission I may try this next. Found a good price for them on FCP Euro

your transmission will be fine with new solenoids and an adaptation reset. you wont need anything else.

[Smurfzilla]

Originally Posted by STR8-6IX

your transmission will be fine with new solenoids and an adaptation reset. you wont need anything else.

I have done a adaptation reset thru MHD without replacing solenoids. I may try that before i try some of the more drastic options. You seem extremely confident its that, have you seen a 335i trans do this (upshift for a second and go back down to the proper gear you're in)?

[STR8-6IX]

Originally Posted by Smurfzilla

I have done a adaptation reset thru MHD without replacing solenoids. I may try that before i try some of the more drastic options. You seem extremely confident its that, have you seen a 335i trans do this (upshift for a second and go back down to the proper gear you're in)?

no, I havent seen that before. but the reason why I am confident with the solenoid replacement is because they control what gear your transmission chooses, and 100k miles is high for original solenoids. they are old and hesitating to go into the right gear.

I was also going to say change transmission fluid, but you already did and there is truly nothing else except for your solenoids that can be causing this.

if you end up changing them, please keep us updated. I would definitely try doing that first before getting a whole new transmission because it may very likely fix your problem and the transmission will feel and shift like new again.

Originally Posted by Smurfzilla

I have done a adaptation reset thru MHD

That's not the proper procedure for your intended purposes.

[Smurfzilla]

Ok thanks. I'll by the solenoids this week and try to get them installed next week. Keep you guys posted. And keep the suggestions coming guys. Thanks

[shadow191]

If it's slipping then that may be a bigger problem than just solenoids. It may still just be the valve body as failing solenoids could cause slow shifts which would result in the "flare" you get right before shifts (slip then shift).

Honestly I wouldn't put too much confidence in what we're saying as we're not there to see what's actually happening. I think you're on the right track. Flash back to stock and then take it from there. I wouldn't just start replacing parts based on some internet stranger who actually hasn't experienced your situation.

Originally Posted by Smurfzilla

It slips in gear. Its all in throttle input. it won't slip unless I;m giving it more throttle then normal. Also I say slip but to me a slip would be acceleration with no movement (aka gear slip) it upshifts quickly and then goes back to the original gear. I've never seen anything about it.

[Smurfzilla]

Originally Posted by FCobra94

That's not the proper procedure for your intended purposes.

Do you have a link to the proper procedure? Or a name so I can search for myself. Or I can just search proper way to reset transmission adaptations.........

LOL ok nevermind.

[Smurfzilla]

Originally Posted by shadow191

If it's slipping then that may be a bigger problem than just solenoids. It may still just be the valve body as failing solenoids could cause slow shifts which would result in the "flare" you get right before shifts (slip then shift).

Honestly I wouldn't put too much confidence in what we're saying as we're not there to see what's actually happening. I think you're on the right track. Flash back to stock and then take it from there. I wouldn't just start replacing parts based on some internet stranger who actually hasn't experienced your situation.

I'm just amazed that the slipping upshifts are something no one has seen before.....usually someone somewhere has been there done that. LOL. The flash back to stock on trans maps is free and replacing solenoids is cheaper then all the other stuff I reckon, repeatedly taking the trans/pan down is not admittedly.

Originally Posted by Smurfzilla

I'm just amazed that the slipping upshifts are something no one has seen before.....usually someone somewhere has been there done that. LOL.

This has been seen plenty of times before...mostly on cars equipped with JB4 though.

[Smurfzilla]

Ahhhhh. Ok when ever I asked around I would get the MOST puzzled look on their faces. In those instances with JB4 equipped cars was the fix mostly the same or was a wide range of possible fixes that cured it.

[Ilma]

I had my tranny start jumping out of gear (4th and 5th under WOT) and also had lots of flare up on upshift and loss of power due to clutch slippage.

Had the tranny rebuilt for around $2,500.

They replaced clutch paks, harder bushings and new solenoids.

Solved the problem.

Shop said the clutch paks were burnt and glazed - so I think you will need to address this especially if you are experiencing slippage.

[Smurfzilla]

Do they sell clutch packs on their own? It was my understanding its basically a complete rebuild at that point?

[Smurfzilla]

clutch = torque converter clutch?