Help..is this the correct transmission

[das borgen]

I've got 325rwhp and a 3.38 diff. I'm not sure it's stronger or not, but by the numbers the 310/320 is rated for 310/320 nm, isn't the 420 rated at 420?

Correct... But what we don't know outside ZF and Getrag is the FOS. I haven't heard any stories of ZF boxes blowing up with 280 ft.lbs of torque at the wheels, but that's anecdotal

The ZF's main weakness seems to be the shift detent pins... And even that is mainly an issue on the 320Z, and less so on the 310Z used in the 95 M3

[nick325xit 5spd]

The E46 m3 smg is the same transmission as the 6 speed, (size, shape, gears, ....) the difference is that it didn't need the internal detents (pins that locate the shifter mechanism) because the SMG unit did that.

(Assuming you are using an E46), I did did this swap last winter, at a MINIMUM, you are going to need a euro E36 6 speed trans support, ($20 new) an E46 clutch and pressure plate, the Euro E36 6 speed shift carrier, shifter and selector rod, and lastly a euro 6 speed driveshaft. I had Rob at UUC make me a package, flywheel, clutch pp, and ssk. I hated the shifter. (Very hard, notchy and mchanical), I got a Rogue ssk, and after a bit of back and forth parts try's, it works great. (The E46 stuff does not work, you need the euro E36 carrier and selector rod)

now how while you are there... How deep is your wallet? Stainless clutch line, flywheel, shifter seal and bushing, release arm, pilot bearing,( e36 will work just fine), E36 325 slave, stainless pivot pin, new guibo and bolts, center support bearing, rebuild the CV or universal.. And a 6 speed shift knob...lol all in, it was about $4500. Including a very low mileage E46 M3 box.

FWIW, the AutoSolutions is way better than the UUC and Rogue, having used all three.

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Crap six speed? Because it's 12kg heavier doesn't make it crap. I too opted for the six speed (euro) at the same time a 3.91 went into my 99M3 (S50B32). The car is my 'fun' car, mostly weekend use, runs up to the crater, auto-x when I have tire funds, so the increased fuel mileage is moot. The reduced engine speed/noise on the highway is nice side benefit.

The car pulls the .86 sixth gear easily. One occasion, on a very late night, I saw 6K rpm and it was still pulling when I decided that was enough on this small island.

The 6spd is less durable under racing conditions than the ZF. Another issue is that it's hard to build a diff that'll hold up under brutal conditions at a short enough ratio to make it worth it. None of this is a major issue in a street car.

[MauiM3Mania]

In short, yes the Getrag S6S is not crap, but the numbers just don't say it's better than the stock ZF for a stock E36 M3 application. That's all I'm concluding and proferring

I was only relaying my experience, not giving advise. I'm not suggesting that anyone fit a six speed to their car, unless they have the desire to do so as I did.

In my case, the six speed/3.91 diff was an afterthought, post euro motor install. A 'why the hell not' idea with a cost that was not insignificant. If I was driving a stockish, 20 year old E36 M3, that would be the last place I'd put ~$3K.

FWIW, the AutoSolutions is way better than the UUC and Rogue, having used all three.

We were able to modify the Auto Solutions shifter (details long forgotten) that was used on the ZF to fit the Getrag. UUC LWF, M5 clutch, etc was a direct fit to the euro Getrag six speed.

[nick325xit 5spd]

I was only relaying my experience, not giving advise. I'm not suggesting that anyone fit a six speed to their car, unless they have the desire to do so as I did.

In my case, the six speed/3.91 diff was an afterthought, post euro motor install. A 'why the hell not' idea with a cost that was not insignificant. If I was driving a stockish, 20 year old E36 M3, that would be the last place I'd put ~$3K.



We were able to modify the Auto Solutions shifter (details long forgotten) that was used on the ZF to fit the Getrag. UUC LWF, M5 clutch, etc was a direct fit to the euro Getrag six speed.

Ronald makes a proper E36 6spd shifter. He occasionally does runs of them when there is sufficient demand, or can run them one-off (at a premium). I'm not sure what the ZF shifter is like, but I suspect that it is *extremely* short throw on a Getrag. I suspect that you would enjoy the proper shifter a lot more.

[pbonsalb]

Turbo owners have found the e46m3 trans to be stronger than the e36m3 trans. But we might make 500-600 lbs tq at the wheels. I broke my first zf320 this year. Supercharged 2006-2010 and turbocharged 2010-2015. Probably 70k boosted miles. Been occasionally drag racing the last few years. Launching on drag radials is rough on the drive train -- fused clutches, broke driveshafts, broke diff output shafts. The trans actually failed during a 5th gear highway pull but maybe the damage started earlier.

[nick325xit 5spd]

Turbo owners have found the e46m3 trans to be stronger than the e36m3 trans. But we might make 500-600 lbs tq at the wheels. I broke my first zf320 this year. Supercharged 2006-2010 and turbocharged 2010-2015. Probably 70k boosted miles. Been occasionally drag racing the last few years. Launching on drag radials is rough on the drive train -- fused clutches, broke driveshafts, broke diff output shafts. The trans actually failed during a 5th gear highway pull but maybe the damage started earlier.

The problem under racing conditions is that the shift mechanism inside the transmission fails. I agree that the gears are stronger, but outside of very high power applications, the ZF320 as a whole tends to last longer under hard use.

[RRSperry]

And maybe, you just don't need and overdrive 6 speed when racing?

[kevinwilly]

It's more like 25lbs (75lb for the ZF S5D320Z vs 100 for the Getrag S6S420G)

FYI, you do know that the gear ratios are identical between both boxes (minus of course the ZF's lack of 6th gear)? The 420G's 6th gear ratio is 0.86:1 (5th gear is 1:1). I very much doubt you can enjoy the added "fun" of the 6th gear when your car probably can't even overcome the drag at those speeds to actually accelerate versus having fun by simply spinning at a few RPMs lower. If the latter is your idea of fun, then by all means have at it because I don't see how the former is viable with anything short of 300whp

It's ok to do mods just for the heck of it, just be aware of the facts and figures! Enjoy it!

Yeah, I know it's the same through the first 5 gears. I'm putting in a 3.64 rear end, though- that's why I mentioned the lower gearing. Unrelated to the transmission.

It's just not really viable to run a 3.64 in a daily driver without a 6 speed. Makes you run something like 4k rpm at 80mph. That's WAY too much.

Also, I have an S50B32 that put down 275-280whp on the dyno last week. After a few mods go on it and it gets retuned it'll probably be close to the 300whp mark.

tl;dr- I know what I'm doing. It's all good, man. But I'm totally going to weigh those transmissions this weekend. I really don't think it's as much as 25 pounds. But it's been a while since I've lifted the 5 speed.

[MauiM3Mania]

Ronald makes a proper E36 6spd shifter. He occasionally does runs of them when there is sufficient demand, or can run them one-off (at a premium). I'm not sure what the ZF shifter is like, but I suspect that it is *extremely* short throw on a Getrag. I suspect that you would enjoy the proper shifter a lot more.

Throws are similar to the AS shifter I have in the E46 M3, which I like.

[nick325xit 5spd]

And maybe, you just don't need and overdrive 6 speed when racing?

No, the tighter gear spacing is an advantage with the right diff. A re-geared 5spd would be equally fast, if not faster (you could optimize), but custom transmissions are expensive (and less likely to be allowed).

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Throws are similar to the AS shifter I have in the E46 M3, which I like.

That's honestly kind of bizarre. The dimensions of ZF and Getrag shifters are very different. But hey, I guess it works.

[pbonsalb]

No, the tighter gear spacing is an advantage with the right diff. A re-geared 5spd would be equally fast, if not faster (you could optimize), but custom transmissions are expensive (and less likely to be allowed).

Is the 6 speed gear spacing really tighter enough to make a difference? I thought the differences were very, very, very minor in 1st through 5th, and that 6th was simply an OD.

[ScotcH]

We use the ZF 6 speed (from a 330i) in our race cars. They have been basically bullet proof so far. We have junkyard trannies in both cars, and only had to replace once in 3 years (3rd gear gone, but unknown previous life). We use them since we run 4:33 diffs and are too lazy to swap, so 6th is needed for top speed we hit (around 145mph). So yes, you DO need overdrive in racing when using a short diff. We had a 4.88 diff as well, but it was too weak.

[kevinwilly]

We use the ZF 6 speed (from a 330i) in our race cars. They have been basically bullet proof so far. We have junkyard trannies in both cars, and only had to replace once in 3 years (3rd gear gone, but unknown previous life). We use them since we run 4:33 diffs and are too lazy to swap, so 6th is needed for top speed we hit (around 145mph). So yes, you DO need overdrive in racing when using a short diff. We had a 4.88 diff as well, but it was too weak.

The Zf 6 speed is a completely different transmission than what has been mentioned in here. Not sure how they compare to the Getrag 6 speed in terms of reliability.

But yeah- depending on gearing you MIGHT need a 6th gear for racing. Wouldn't going to a 4.88 diff almost just shift all your gears down by one? Meaning that first gear is useless, second gear is BASICALLY the same as stock first gear, third gear is basically the same as stock second gear, etc.

I mean- there's a point where extra gearing in your rear end really isn't helping you that much.... I'd need a spreadsheet of effective final gear ratios, though.

[ScotcH]

The Zf 6 speed is a completely different transmission than what has been mentioned in here. Not sure how they compare to the Getrag 6 speed in terms of reliability.

But yeah- depending on gearing you MIGHT need a 6th gear for racing. Wouldn't going to a 4.88 diff almost just shift all your gears down by one? Meaning that first gear is useless, second gear is BASICALLY the same as stock first gear, third gear is basically the same as stock second gear, etc.

I mean- there's a point where extra gearing in your rear end really isn't helping you that much.... I'd need a spreadsheet of effective final gear ratios, though.

Agreed, I was just saying that 6th gear can be useful. We use 4.33 and 4.44 now. The 4.88 was useful for one of our tracks (slow, tight), but they changed the layout, so now it's no good. Our engines have a narrow power bands, so a short ratio works well.

[jbarela]

Hey there all..thanks so much for all the posts as it is really helping me. Why do i want the mod...95 325i vert with s50 cams and turner tune..338 gears in the back..dont like the engine running high rms at 80 mph on freeway....however agame changer occured and i "think" it is still the appropriate mod..picked up a solid strong s50 with dinansupercharger...going to stage 2 with aftercooler,tune,maff pluggs etc..just not going to change the pullys. I dont race my car but i red line through gears getting on freeway...10 percent of time shifting at 6grand. I like to drive spirited for sure...but i dont know how to drive a supercharged engine in regards to wahts good and not good...for example i always down shift gears to stop..anyhow thanks for the pics and now i know what to look for..

[Rob Levinson]

Although a cool mod, I don't understand why someone would want to spend the money on a heavier, less strong transmission for such minimal gains (if even) on gas mileage.

E46 M3 club racers swap out the crap 6spd for ZF 5spd for the weight loss and durability gains

Actually, the E46 M3 transmission is extremely strong. Mechanically, it's the same internals as the E39 M5 and mostly the same as a turbo Supra. Not wimpy cars. What kills them is slamming gears without full clutch disengagement or nowhere-close revs. Racers change to the 5-speed because it's cheap, plentiful, and weighs a little less.

For street use where you need good low-speed acceleration and want low high-speed cruising rpm, the 6-speed and an appropriate final drive ratio is a fantastic combination for the E36.

[das borgen]

Actually, the E46 M3 transmission is extremely strong. Mechanically, it's the same internals as the E39 M5 and mostly the same as a turbo Supra. Not wimpy cars. What kills them is slamming gears without full clutch disengagement or nowhere-close revs. Racers change to the 5-speed because it's cheap, plentiful, and weighs a little less.

For street use where you need good low-speed acceleration and want low high-speed cruising rpm, the 6-speed and an appropriate final drive ratio is a fantastic combination for the E36.

thanks for saying again what all has been beat to death time immemorial and again in this thread. Have you any actual input aside from repeating what's been said? All you've said here has been said in the thread already here over the past few days, you know?


I'm genuinely surprised you didn't schill for any of your fantastic products also in your post. Maybe with age does come wisdom

[Rob Levinson]

thanks for saying again what all has been beat to death time immemorial and again in this thread. Have you any actual input aside from repeating what's been said? All you've said here has been said in the thread already here over the past few days, you know?


I'm genuinely surprised you didn't schill for any of your fantastic products also in your post. Maybe with age does come wisdom

"Ease down, Ripley, ease down! Ripley, you've blown the transaxle! You're just grinding metal!"

That's exactly what I pictured just now. LOL!

Yeah, I have a bit more experience than the average bear when it comes to these. I tested and wrote the most-quoted swap guide for this gearbox into the E36. We've performed countless of them here in customer cars and our own cars, and I've yet to see these transmissions fail any more or less than the 5-speeds.

So, yeah, there might be some value to my input. ;-)

[bmwm3smg]

HI Guys,

Seeing you talk about SMG and i was wondering if i could ask a question:

I'm the owner of a E36 1999 SMG1 and i'm seriously looking for going to manual, this due to a crappy SMG module.

I'm now trying to find out what kind of things i need to replace but all i can find is information about changing the E46 instead of E36.

Do you know what the difference is between installing a manual transmission on a E36 instead of a E46?

Thanks a a lot for the reply