E8X MT or DCT? I am conflicted on my next upgrade

rhodesman

Corporal
Mar 21, 2017
186
78
0
44
Maryland
rhodesman.com
Ride
2010 BMW E88 N54 135i
Currently my 2010 135i AT transmission is dying, she slips if I start to dial up the power. I was planning on pulling the engine for routine maintenance and a good cleaning over winter and would love to swap out the AT for something...better. However, I have been going back and forth in my head over the past year on which route to go down and I just cannot decide what to do.

On one hand, the MT is a full on experience, nothing can compare to rowing through the gears. However, the DCT is quicker at shifting and when going to the drag strip, would be a huge advantage to cutting down my 1/4 mile times. Also, I have grown fond of the paddles which I have converted to the M3 DCT ones so I have 'proper' paddles vs the push/pull crap the car came with.

Some questions I don't have clear answers to is what extra hardware should I get to accompany the swap? Obviously the MT has a bit more hardware to install over the DCT but things like cooling or fitment on the block and/or extra needed components has me unsure of the greater task at hand. I'm looking at salvaged transmissions and parts pulled from wrecked cars as I can get a complete kit (drive shafts, diffs, shifters, wiring, etc.) for less than a brand new transmission. I do plan to put new upgraded clutches in and do any other routine services before installing so I think this is a good route to go but curious with other peoples experience is like going salvaged over new.
 

KClemente

Sergeant
Nov 26, 2019
280
145
0
Ride
E90 335i
If you haven't made up your mind already, clutches on a dct are way more expensive than a high end twin disc clutch. Though the DCT should handle some decent power

It's funny because I am currently thinking about going MT to DCT on my car now.
 

DirtKurt

Corporal
Nov 5, 2016
179
196
0
NH
I swapped from At to Dct in my 09 335. After driving my brothers e90 m3 I knew the dct was the only way to go. I wanted to go with the most durable best performing option and for me that was the dct.
However if you are mainly looking for 1/4 mile times you may not be happy with the dct. It can be really difficult to get it to launch without blowing the tires off. Much harder than the auto
 

Begood69

Corporal
Nov 13, 2016
234
113
25
Fayetteville, NC
Ride
335i N54 Predator 3.2L stroker
I liked my DCT.. but now swapped to 8hp70.. so if anyone needs a DCT/oem harness, let me know (optional big momma pan). PM me or 910-364-8118 john