E46 325I 6 speed swap

[Machak07]

Good day everyone, so this has been a project I've been working on the past few months, even ended up buying incorrect parts........I now have a 2007 335 transmission for sale! if anyone is interested lol.....I guess this is more or less a verification than anything, which 6 transmission will work on the 2005 325? I'm seeing alot of people doing this "poor man supercharger" upgrade...and I got the 3.46 dif ready to go, just want to put on a 6 speed since I do alot of highway driving. Do I need to be searching for a 330 transmission? any 330 (besides X)? I'm in search for a GS6-37BZ, if this is correct.


Thanks!

[legoman67]

you need a 6 speed transmission from an E46. They were found in the later 330's and M3's. They are rather rare compared to the 5 speed... i actually have 1 sitting in my basement, but shipping it would kill.

[dworthy]

+1

You would have to do less modification with the M-3 6-speed than the 330i, as they use a different style shift linkage.

The other thought would be to get a different diff, as in getting a 3.23 from the 325xi or maybe even a 3.07 from the 323i.

[Machak07]

Yeah that's what I'm wondering...I figured BMW has kept the same bolt patterns on the bellhousings for generation....I had a few people tell me that the 335 transmission would work....and surprisingly I think it would bolt up...just, the shifter linkage is way different. No where on the body to bolt it on underneath. Also, driveshaft is different on the E92, giant nut that threads on the dif, not a 3 bolt flange I'm used to seeing on bmws.

[Machak07]

Dworthy - so the 330 uses a different shifter assembly from the 325 and m3? What kind of modifications will be involved useing the 330? I can see the 6 speed needing a shorter selector rod due to the length of the trans being longer.

But yeah I have an 3.46 from an automatic. I've already tried with my factory 5 speed and it is a torque monster! Just want that 6 speed to lower my cruising RPMs.

[dworthy]

It should be the same as the E-9x shift linkage, where you have a single support rod, but the attachment to the trans is different. The support in the back uses the same bushing for all of them: http://www.realoem.com/bmw/enUS/part...&q=25111222015

You would need the whole link and assembly, but I have a feeling that the 335i transmission would fit the M-5x motors. What gives me a clue is they all use the same pilot bearing and the covering place looks very similar. Take it all with a grain of salt as I have never put a E-9x transmission into a E-46.

All 325i sedan and wagon built after YM01 came with the 3.46 for the 5-speed IIRC.

[Machak07]

Well, i know it should bolt up....everything around the bell housing looks exactly the same....I put my 325 up on my lift last weekend and removed my exhaust and driveshaft to verify everything will be correct, and noticed this is what my shifter looks like: (upon a quick Google search)
https://www.google.com/search?q=e46+...1Idq2gNijcM%3A

The 335 trans I have looks really close to this shifter assembly:

https://www.google.com/search?q=335i...qHyYC-a3kTM%3A

Hopefully those links work for you....

From the shifter hole (going into the dash) with the 335 shifter assembly the selector rod will go back another 2-3 inches from the factory bushing spot...with no mounting hole, so i would have to prob make some new holes....ew.....that is...if the transmission will line up to the 335 assembly in the shifter hole. So I'm not sure this is going to work.

So your saying the e46 330 is the same as the E9X assembly?

[dworthy]

What I would use is the E-46 6-speed shifter, as they would be similar mounting points to the E-9x transmission. This would allow you to check prior to install, and will run 25 bucks for the shift arm. I am interested in your swap, as I too have a 5-speed in the wagon, and it gets ugly around 120mph with the rev's taching out on the autobahn.

[Machak07]

Well, im doing some searching around...looking to see what the e46 6 speed shifters look like. I'm not finding much luck, but i did find one write up on another forum and it looks kinda similar to the E9X shifter assemblies....http://forum.e46fanatics.com/showthread.php?p=16891357 if you scroll down a ways he shows his shifter assembly...looks kinda close...I'm wondering does it have the be this ZHP or do all E46 six speed shifters look like this?

[dworthy]

Yes, the ZHP has a "short shifter" while the carrier or the shift arm should be the same as all the other E-46's 6-speed. You don't need the ZHP shift lever, for you can use anyone from a E-46 330i 6-speed.