6AT Transmission Service……what else should I do when I’m in there?

iqraceworks · 10-21-2019, 12:00 PM

I’m getting ready to order all the parts for a transmission fluid service on my “new to me” 07’ 335i with 100,000miles on it. I have no idea if the fluid and filter have ever been changed before.
So if I’m going to be in there with the pan off….what else should I replace? I know there are common things that everyone replaces in there (plug adapter & sealing sleeve), but what about stuff like the valve body to case sleeves and the shift solenoids?
I think it’s smart to replace “known to fail” type stuff when you are in there, but I also think that sometimes you are better off leaving some of the “hardly ever fails” stuff alone……not sure I want to pull the valve body out unless I absolutely have to.
Thoughts?

mweisdorfer · 10-21-2019, 12:14 PM

Quote:

Originally Posted by iqraceworks

I’m getting ready to order all the parts for a transmission fluid service on my “new to me” 07’ 335i with 100,000miles on it. I have no idea if the fluid and filter have ever been changed before.
So if I’m going to be in there with the pan off….what else should I replace? I know there are common things that everyone replaces in there (plug adapter & sealing sleeve), but what about stuff like the valve body to case sleeves and the shift solenoids?
I think it’s smart to replace “known to fail” type stuff when you are in there, but I also think that sometimes you are better off leaving some of the “hardly ever fails” stuff alone……not sure I want to pull the valve body out unless I absolutely have to.
Thoughts?

I'd leave the sleeves & solenoids alone for now. Probably at 150,000 miles and beyond is when you need to consider changing out the various sleeves.

The megatronic sleeve is notorious for leaking in the e90. I'd change that for sure.

If you buy 12-14 qts of oil, you can flush out all the trans fluid in the torque converter via the hot line on the trans cooler. You will need the special blue to take the hydraulic line off the trans cooler, but you can buy it for about $13-4 on Amazon.

I'd also change out the fluid every 50,000 miles from here on in. The internal parts are not brand new anymore.

mweisdorfer · 10-21-2019, 03:56 PM

CTA Tools 3466 BMW Power Steering and Transmission Line Disconnect Tool https://www.amazon.com/dp/B009VI9P62..._UwGRDbJ98WKSZ

How to flush -

- Drain the old fluid & change the pan filter & fill with new fluid until it starts to come out.

- Mark a milk jug at the 3qt. Mark.

- disconnect the hot (return) line going from the trans to the trans cooler & put it into the milk jug.

- Have someone start the engine & watch the milk jog fill up to 3qts; tell your helper to shut the engine off.

- Repeat 3x or so. You should see the trans fluid become bright red coming into the milk jug.

- Connect the trans line back to the cooler

- Do a final fill until fluid starts to run out; put the fill plug in. Turn on the engine & run it through the gears a few times at a minimum.

- You need a way to measure the temp of the trans fluid either by way of a laser type thermal gun, or software like INPA, BIMMERGEEKS, ISTA D, or some other device.

- The temp needs to be 86 to 122F. When it reaches this range, take the fill plug out & fill the pan with fluid until it start me to come out of the fill hole & put the fill plug back in & tighten down.

Now 99.9% of the fluid in the trans is brand new vs 50% at best

relative4 · 10-21-2019, 10:21 PM

Definitely drop the valve body and replace the double-square seal. Recommend the tube seals too, and the solenoids aren't a bad idea.

turbohugh · 10-22-2019, 12:15 AM

To do this right you have to drop the pan.
Once you drop the pan you should drop the mechtronic
Once you drop the Mechtronic you should replace the electronic connector sleeve, the tubes and the square blocks.
Then replace the pan with the new pan [filter is built into the pan].
Then add the new fluid following the procedure above.

Don't cheap out. IF you haven't gotten codes consider yourself lucky. IF you do the sleeves and block you may avoid a E-clutch fault [which basically will mean a new transmission].

Theres's a lot of credible information about why you should replace all the rubber sleeves during the service. YMMV but this is the recommended 'while youre at it' .

10-21-2019, 12:00 PM	#1
iqraceworks Brigadier General 1994 Rep 3,725 Posts Drives: 2007 335i Join Date: Aug 2019 Location: Missouri iTrader: (0)	6AT Transmission Service……what else should I do when I’m in there? I’m getting ready to order all the parts for a transmission fluid service on my “new to me” 07’ 335i with 100,000miles on it. I have no idea if the fluid and filter have ever been changed before. So if I’m going to be in there with the pan off….what else should I replace? I know there are common things that everyone replaces in there (plug adapter & sealing sleeve), but what about stuff like the valve body to case sleeves and the shift solenoids? I think it’s smart to replace “known to fail” type stuff when you are in there, but I also think that sometimes you are better off leaving some of the “hardly ever fails” stuff alone……not sure I want to pull the valve body out unless I absolutely have to. Thoughts? __________________ 2007 335i, BMS DCI, BMS Chargepipe w/Tial BOV, ARM Catless Downpipes, silicone inlets, Bilstein B12 Prokit Suspension, Whiteline subframe bushings, Front/Rear M3 control arms, G-Plus FMIC, Stage 2 LPFP, Custom E40 tune by Justin (V8Bait), xHP stage 3 transmission flash, RB Two Turbos....10.90 @ 128mph
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10-21-2019, 03:56 PM	#3
mweisdorfer Major General 1903 Rep 6,968 Posts Drives: 2007 Black/Black 335i e90 Join Date: Apr 2011 Location: Holly, MI iTrader: (0) Garage List 2007 BMW E90 335i [0.00] 2008 bmw x5 [0.00]	CTA Tools 3466 BMW Power Steering and Transmission Line Disconnect Tool https://www.amazon.com/dp/B009VI9P62..._UwGRDbJ98WKSZ How to flush - - Drain the old fluid & change the pan filter & fill with new fluid until it starts to come out. - Mark a milk jug at the 3qt. Mark. - disconnect the hot (return) line going from the trans to the trans cooler & put it into the milk jug. - Have someone start the engine & watch the milk jog fill up to 3qts; tell your helper to shut the engine off. - Repeat 3x or so. You should see the trans fluid become bright red coming into the milk jug. - Connect the trans line back to the cooler - Do a final fill until fluid starts to run out; put the fill plug in. Turn on the engine & run it through the gears a few times at a minimum. - You need a way to measure the temp of the trans fluid either by way of a laser type thermal gun, or software like INPA, BIMMERGEEKS, ISTA D, or some other device. - The temp needs to be 86 to 122F. When it reaches this range, take the fill plug out & fill the pan with fluid until it start me to come out of the fill hole & put the fill plug back in & tighten down. Now 99.9% of the fluid in the trans is brand new vs 50% at best
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10-21-2019, 10:21 PM	#4
relative4 Major 611 Rep 1,272 Posts Drives: '08 335xi E90 MT stage 1+ Join Date: Feb 2019 Location: Denver, CO iTrader: (0)	Definitely drop the valve body and replace the double-square seal. Recommend the tube seals too, and the solenoids aren't a bad idea.
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10-22-2019, 12:15 AM	#5
turbohugh ASCMA General 51 Rep 157 Posts Drives: E90-N54 <>E36 328Vert Join Date: Nov 2015 Location: Somewhere in Washington DC iTrader: (0)	To do this right you have to drop the pan. Once you drop the pan you should drop the mechtronic Once you drop the Mechtronic you should replace the electronic connector sleeve, the tubes and the square blocks. Then replace the pan with the new pan [filter is built into the pan]. Then add the new fluid following the procedure above. Don't cheap out. IF you haven't gotten codes consider yourself lucky. IF you do the sleeves and block you may avoid a E-clutch fault [which basically will mean a new transmission]. Theres's a lot of credible information about why you should replace all the rubber sleeves during the service. YMMV but this is the recommended 'while youre at it' .
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