AT Transmission Question.

[terryd5150]

I've got a 2008 335i coupe sitting in my garage begging me to finally get off my butt and do something with it.

Before I go down that road though, the current transmission shifts like sh!t, although it doesn't throw any codes.

Does anyone know first-hand which transmission this car has, 6HP19 or 6HP21?

Car is a 10/07 build.

I've done a lot of searching but all I can find are people taking "best guesses" based on wiki-type data, and even ZF seems to contradict themselves.

I'm looking for someone that's been under an '08 coupe that can say, definitively, that it has model "XX".

[topher454]

What is the last seven of your VIN#? and I'll look it up in BMW EPC

[psychosinmylobby]

Your 2008 has a 6HP21 which is a gen 2 of a 6HP19. BMW called it 6HP19Z; Z for technical update.

I know this first hand since I did the Zip kit on my 2007 (3/07 build date) and it took the Gen 2 6HP21 kit. Valve body layout matches exactly that of the Gen 2.

[terryd5150]

Your 2008 has a 6HP21 which is a gen 2 of a 6HP19. BMW called it 6HP19Z; Z for technical update.

I know this first hand since I did the Zip kit on my 2007 (3/07 build date) and it took the Gen 2 6HP21 kit. Valve body layout matches exactly that of the Gen 2.

Thanks for chiming in, Psycho.

Interesting that you mentioned the Zip kit; I was strongly considering one.

Do you feel it was a worthy investment?

[psychosinmylobby]

I did the zip kit at the same time I was trying to resolve a leaking mechatronic sleeve. If there wasn't anything wrong with your transmission in the first place I would advise against it. I did not feel like it made my shifts any firmer. I did start feeling a delayed 1-2-3 shifts under low load after the install but that might be due to the Redline D4 fluid I used instead of the OEM fluid.

If you are considering it, understand that in addition to the zip kit, you will need to purchase a separator plate for the transmission. This ranges anywhere from 60-100 dollars depending on which one you have and where you get it.

What symptoms are you facing with your transmission?

[terryd5150]

I did the zip kit at the same time I was trying to resolve a leaking mechatronic sleeve. If there wasn't anything wrong with your transmission in the first place I would advise against it. I did not feel like it made my shifts any firmer. I did start feeling a delayed 1-2-3 shifts under low load after the install but that might be due to the Redline D4 fluid I used instead of the OEM fluid.

If you are considering it, understand that in addition to the zip kit, you will need to purchase a separator plate for the transmission. This ranges anywhere from 60-100 dollars depending on which one you have and where you get it.

What symptoms are you facing with your transmission?

Several.

- Very weak shifts and sometimes no shift at all, I have to let off the gas and slow down for it to change gears (when pushing it hard).

- When it shifts, sometimes it sounds like a manual that someone hit the clutch too quickly when shifting gears as there's a slight rev increase and time lapse before it finds the next gear (during DD).

- Quite often, its as if it doesn't seem to know or can't make up its mind on which gear it should be in - the shift points seem make no sense (during DD).

The car's under warranty, but if I take it in now I'll know I'll get told "there's no codes so we're not gonna touch it".

[psychosinmylobby]

Did you spot any leaks from the transmission? I got symptoms 1 and 2 (but occasional) from a leaking mechatronics sleeve and low fluid.

If you can have the SA sit in your car and demonstrate those symptoms, that would be best. I doubt you want to be arms deep in transmission fluid (yuck!)

[terryd5150]

Did you spot any leaks from the transmission? I got symptoms 1 and 2 (but occasional) from a leaking mechatronics sleeve and low fluid.

If you can have the SA sit in your car and demonstrate those symptoms, that would be best. I doubt you want to be arms deep in transmission fluid (yuck!)

No leaks that I know of, but I haven't been under the car.

There's nothing on the floor of my garage and nothing in my parking space at work.

I think I may do the zip kit, solenoids, sleeve, pan & filter, and BMW brand fluid and then reset adaptations.

If that doesn't do it, then I'll flog the sh!t out of it until it either throws a code or won't drive.

Then I'll take it in for a warranty repair.

[psychosinmylobby]

Mine was a very slow leak and the fluid dried onto the bottom of the transmission fluid pan so it didn't make it to the floor either. Additionally, there is a splash shield there so you might not see fluid on the floor unless the leak is significant.

Sounds like you got a plan there. I think you should go for it and see if that fixes it. You can PM me anytime if you have any questions regarding the Zip Kit install.

[terryd5150]

Mine was a very slow leak and the fluid dried onto the bottom of the transmission fluid pan so it didn't make it to the floor either. Additionally, there is a splash shield there so you might not see fluid on the floor unless the leak is significant.

Sounds like you got a plan there. I think you should go for it and see if that fixes it. You can PM me anytime if you have any questions regarding the Zip Kit install.

Thanks, Psycho; I may tap on your shoulder in the near future.

Some upfront questions, though: the zip kit is described as not requiring special tools. It reads like its an easy install.

Your thoughts?

Also, can it be installed with the transmission still in the car?

Was planning on a DIY in my garage....

[psychosinmylobby]

Requires quite a bit of patience and a very ventilated room (transmission fluid stinks). Aside from the the usual screwdriver set (torx is required), you will probably need needle nose pliers, precision screw driver (to remove clips and such) to assist the install.

Be very careful when separating the halves, there are checkballs (little plastic balls) and check valves that may fall out. It should be separated with the VB flat on the table. Order the correct separator plate and have it ready before starting the install.

The zip kit has to be done with the VB fully uninstalled. There are several bolts holding the VB to the transmission that goes complete though which wont allow you to separate the VB into its halves.

I did the DIY in my own garage as well. It's very doable as a DIY.

[j_hynson]

The car's under warranty, but if I take it in now I'll know I'll get told "there's no codes so we're not gonna touch it".

I would keep taking it to them saying that the issues are happening and make sure you have your own paper trail from the dealer for the complaints. This way if something happens when out of warranty you can fall back on it and say this was something you tried to have addressed multiple times