[HairyCannonball]

Looking for the groups expert advice about the transmission on my newly acquired 2011 335d. The car has 74,000 miles on it, is still literate, has obviously been very well cared for, and came with all dealer service records since new. However, I have no records of any non dealer performed service. I know at least some work was done outside the dealer, as it has a Forge boost hose. That said, there is no record of the transmission fluid having been changed, so I am planning to do that, along with some other preventative maintenance soon.
The car runs and drives extremely well, however, I have noticed one thing that seems strange to me. Under light acceleration, and ONLY under light acceleration, there is a very slight flare shifting from 2 to 3. It is very slight, the shift still feels perfectly smooth, no jerking, no harsh engagement, no odd noises, no other anomalies. The flare is about 100rpm. Under moderate or greater acceleration there is zero flare. At any level of acceleration, when manually shifting, there is zero flare as well. Downshifting is smooth, quiet, and normal. My questions are, 1. Is this an issue? 2. Will a fluid and filter change help this. and 3? Do you think it is necessary to replace the mechatronic sleeves while the pan is off? I would prefer to not disturb if nothing is wrong.
Thanks for any input.

[335dlci]

This flare is the largest complaint about the zf 6hp for these vehicles. You can get transmission tunes to help with this feeling. So 1. No. 2. No but overdue maintenance is good to catch up on. 3 yes do everything.

[Yozh]

Definitely do sleeves

[HairyCannonball]

Guys, thanks. Sleeves are on their way. Already had the pan/filter, and fluid.

[BB_cuda]

Bridge adapter and mechatronic sleeve too. You need to pull that sleeve to remove valve body anyway. Mine is due for all of this even though fluid only has about 26,000 miles on it.

[HairyCannonball]

Originally Posted by BB_cuda

Bridge adapter and mechatronic sleeve too. You need to pull that sleeve to remove valve body anyway. Mine is due for all of this even though fluid only has about 26,000 miles on it.

Yes. Have those coming along with the sleeves. Will do all when I am back in the country.

[BB_cuda]

Originally Posted by BB_cuda

Bridge adapter and mechatronic sleeve too. You need to pull that sleeve to remove valve body anyway. Mine is due for all of this even though fluid only has about 26,000 miles on it.

I did my transmission service yesterday. I was mistaken as my records show it was 36,500 miles since last new fluid change. The fluid looked pretty clean. The service was needed for the new sleeves, bridge adapter, and mechatronics sleeve. I have a separate aluminum pan so I changed the separate filter sold at thectsc.com meant for B7 Alpina and E53 E70 metal pan units. I also used the green paper gasket with Permatex 51813, anaerobic sealant. The old paper came off fairly easily with an exacto razor blade. I used ~ 7.5L of the ZF LG6 fluid.
The rear mechatronics sleeve was a bit easier this time thanks to advice from 335dlci. He suggested I lever against adjacent structure to better push it all the way in. I had struggled with this aspect on the other M57 we own.

Per yozh advice, I removed the transmission cross member after putting jack stand with block of wood at rear of transmission. This made an easier job of removing the mechatronics connector and sleeve itself. I looked real careful at the keyway on the sleeve prior to removal with the mechanics mirror and flashlight. It is not quite straight down position. More like 5-5:30 using clock dial analogy.

After dropping valve body down and doing the required sleeves and bridge adapter replacement, reinstallation of the mechatronics wasn't that bad. Aligning the shifter pawl was no issue and then got a couple long T40 screws started to hold it in place. I torqued Mechatronic to 8 NM (71 in-lb). I use the in-lb range torque wrench as ft-lb range one has no ability for accuracy down at 5.9 lb-ft.

Installation of the new mechatronics sleeve was a little silly for me but I found a method. Here goes. I aligned the key way well and made sure it was aligned with the connector shell's keyway notch. I couldn't lever against anything with the cross member off. So, I put the cross member back on and removed jack stand. I then placed a short ~3" block of wood in against the mechatronics sleeve. I lever against the cross member to push on the wood using a short OEM car lug nut bar. It worked really well as I gently nudged it in further and further in. I went back and forth between more nudging and trying to push up the white clip that locks the sleeve in place. I was finally able to get the white clip to snap upward. Be gentle on it as it would suck to break it.

I then had to take the cross member back off with same jack stand in order to connect the harness connector to the mechatronics sleeve. There may be better ways to do this but it worked out for me. My aftermarket exhaust is a bit in the way for accessing the passenger side screws to the crossmember but i made due with a 13 mm combination wrench. After connector reinstall, cross member went right back on for last time.

Installed alum pan with green paper gasket and Permatex 51813 anaerobic gasket maker. I'm not a fan of using RTV in a transmission unless the glue is allowed to cure for 12 hours/overnight. Jess Bohl recommended the anaerobic type to me long time ago and I trust him as he is a great mechanic.

Did the normal routine of fluid fill, start, add more fluid until runs out the fill hole. Used ~ 7.5L of Lifeguard 6 fluid.

[335dlci]

Good write up cuda. Always happy to share some tricks

[Yozh]

Nice and as always a detailed write up. Thank you.

[Persian Whisperjet]

Originally Posted by Yozh

Nice and as always a detailed write up. Thank you.

Yes! This group still has some tricks up its sleeve!

[Yozh]

BB_Cuda is an OG. Too bad most got pushed away. So much collective knowledge been here.

[HairyCannonball]

Very detailed write up Cuda. Thank you!!!! I appreciate the advice and information. Looking forward to getting to work on my car when I am back in the States.

[335dlci]

Originally Posted by Yozh

BB_Cuda is an OG. Too bad most got pushed away. So much collective knowledge been here.

Yeah a lot of OG still here. I still perfer e90post. Its not full of vw tards and othrr chesp owners who just ask for everything for free without even diagnosing anything themselves.

[BB_cuda]

Originally Posted by Yozh

BB_Cuda is an OG. Too bad most got pushed away. So much collective knowledge been here.

Thanks to Yozh and 335dlci but I was actually sharing tricks that you two told me. I had struggled with the connector sleeve last time around and I was determined to not let it beat me again.

[HairyCannonball]

One more probably stupid question. Is it best to disconnect the battery before removing the electrical connector to the mechatronic unit?

[BB_cuda]

I don’t know the official propaganda but I don’t disconnect the battery. Not sure if there is a risk so it wouldn’t hurt to disconnect (unless your FRM is still original then I dunno ...).

[HairyCannonball]

I believe my FRM is original, but will need to scour the service records to be sure. That said, maybe is best if it hasn't been replaced that it fails now before the extended warranty expires. Build date on mine was 03/11, in service date sometime after that obviously. Should have a couple more months at least. But the FRM is what I was thinking about concerning battery d/c. I would rather fry a FRM than a mechatronic unit though. But, if you have never had any issues....

[Yozh]

Disconnecting the battery does run you a risk of FRM going bust.

[335dlci]

No need to disconnect battery.

[HairyCannonball]

Originally Posted by 335dlci

No need to disconnect battery.

Again, thanks guys. I appreciate the help and advice.

[BB_cuda]

Nice folks at DUDMD can take care of your FRM BEFORE it goes bad. Also guys on here that can do this too.

Maybe its smarter to get it reprogrammed at your convenience rather than it bricking at a bad time for you.

[Yozh]

Originally Posted by BB_cuda

Nice folks at DUDMD can take care of your FRM BEFORE it goes bad. Also guys on here that can do this too.

Maybe its smarter to get it reprogrammed at your convenience rather than it bricking at a bad time for you.

Not everyone updates to the latest firmware to avoid bricking.