2006 Pontiac G6 F40 6 speed manual transmission

[zofo61]

Will this bolt up to a 3400?

[El_Diablo]

yes, not sure on the newer VVT engines but the 3500 shared the same bolt pattern so as long as its the same bellhousing as the one used with the 3500 then i guarantee you it will bolt up

[Blackrider]

yes, not sure on the newer VVT engines but the 3500 shared the same bolt pattern so as long as its the same bellhousing as the one used with the 3500 then i guarantee you it will bolt up

The F40 never came with the LX9, it was only an option on the LZ9 (3900VVT) and some Saabs.

Regardless it will bolt up to a 3400.

[El_Diablo]

meh, wasn't sure, not really a huge fan of g6's, to common around here

either way, thanks for clarifying

[LeftVentricle]

The F40 never came with the LX9, it was only an option on the LZ9 (3900VVT) and some Saabs.

Regardless it will bolt up to a 3400.

Gen1/2 motors as well. One of the guys at Pennock's slapped it onto his Fiero's 2.8 with little difficulty. I'll see if I can dig up the thread...

[zofo61]

It is a FWD trasnny ....yes?

[sharkey]

axles are a huge deal, you need custom adaptors made and then you need to build your own axles out of other gm axles, not an easy thing to do. the clutch is a big deal, the stock 3900 clutch is a dual mass, its 11/16" thicker flywheel. it will all bolt to a previous motor, but dual mass isnt really known for good performance.

[zofo61]

Thanks......I was hoping this was my answer to a manual shift ...but seems ....as usual....too good to be true......Oh well.....................

[Blackrider]

Thanks......I was hoping this was my answer to a manual shift ...but seems ....as usual....too good to be true......Oh well.....................

Getting custom axles done up is not that huge of a deal.

[Joseph Upson]

Actually custom axles are more a necessity for the Fiero due to the track, in the average full size front wheel drive car the G6 axles will probably go right into place. Although I haven't said much about it in the 3900 thread that's the tranny I have installed with it. The right side intermediate shaft and axle went right into place except for needing to change the outboard joint cup which has the larger spindle like what's found on the larger cars. The left side axle required some work however Moser can respline axle ends to meet joint requirements only you must insist they match the original spline and snap ring dimensions or you'll end up with a permanent joint installed on the axle end.

The Cobalt SS and Saturn Redline 5 speed uses the same inboard joint splines however the intermediate shaft is female like that used on the Saab, and the outboard joint has the smaller spindle end that will bolt directly to the Fiero hub, the overall axle is a little shorter than that found on the G6. There are two 5 speeds for the Cobalt and Redline, only the Supercharged models have the correct 5 speed with interchangeable axles to the 6 speed.

As for the dual mass flywheel performance it's heavier than the old 60 degree V6 flywheel but then it came attached to a 3.9L V6, it also has a much stronger clutch assembly which the builder for my Kevlar disc measured about a 2000 lb clamping force in the stock pressure plate.

Here is the link to what I gathered in my work with it so far;

http://www.fiero.nl/forum/Forum2/HTML/078656.html

[Blackrider]

Actually custom axles are more a necessity for the Fiero due to the track, in the average full size front wheel drive car the G6 axles will probably go right into place. Although I haven't said much about it in the 3900 thread that's the tranny I have installed with it. The right side intermediate shaft and axle went right into place except for needing to change the outboard joint cup which has the larger spindle like what's found on the larger cars. The left side axle required some work however Moser can respline axle ends to meet joint requirements only you must insist they match the original spline and snap ring dimensions or you'll end up with a permanent joint installed on the axle end.

The Cobalt SS and Saturn Redline 5 speed uses the same inboard joint splines however the intermediate shaft is female like that used on the Saab, and the outboard joint has the smaller spindle end that will bolt directly to the Fiero hub, the overall axle is a little shorter than that found on the G6. There are two 5 speeds for the Cobalt and Redline, only the Supercharged models have the correct 5 speed with interchangeable axles to the 6 speed.

As for the dual mass flywheel performance it's heavier than the old 60 degree V6 flywheel but then it came attached to a 3.9L V6, it also has a much stronger clutch assembly which the builder for my Kevlar disc measured about a 2000 lb clamping force in the stock pressure plate.

Here is the link to what I gathered in my work with it so far;

http://www.fiero.nl/forum/Forum2/HTML/078656.html

40LBS flywheel assembly? No wonder the throttle response on the 3900 sucks. Would there be any way to go aftermarket on this?

I understand 2000LBS clamping force is pretty decent, however what are we talking in regards to engine torque out put, how much power can this clutch take?

[Joseph Upson]

Hard to say for sure if the flywheel is the reason behind the throttle response since it has an electronic throttle body and there is a plus and minus for both lightweight and heavy flywheel assemblies.

There is about two aftermarket combos most of which use the Spec clutch which lately has a lot of skepticism following several similar very, very low mileage clutch failures even during proper break in. You'd have to search for them on the Fiero forum.

The 3900 is rated at 240/240, and the Kevlar friction material in place of the stock material combined with the high pressure plate clamping force originally designed for a car that nearly weighs a 1000 lbs more than my car really doesn't cause me any concern with holding capacity. The guy that built my disc using the stock hub said that the size and clamping pressure relative to the stock Fiero clutch indicates that the standard clutch used on the G6 is pretty stout.

[Blackrider]

Hard to say for sure if the flywheel is the reason behind the throttle response since it has an electronic throttle body and there is a plus and minus for both lightweight and heavy flywheel assemblies.

It probably has something to do with it, that’s one of my complaints with the 3900 is the throttle response is awful.

What are some of the downsides of a lighter clutch? I understand that due to the reduction in rotating mass the engine will not only rev quicker however it will also lose revs just as quick.


Sorry I didn’t mean to hijack this thread.

[Joseph Upson]

It probably has something to do with it, that’s one of my complaints with the 3900 is the throttle response is awful.

What are some of the downsides of a lighter clutch? I understand that due to the reduction in rotating mass the engine will not only rev quicker however it will also lose revs just as quick.


Sorry I didn’t mean to hijack this thread.

Exactly, inertia between shifts is the trade off. If the engine is producing enough power the added weight will not be much of an issue. It weighs less than some of the V8 flywheels I've encountered including the one used on the 4.3L which I doubt is a 240 hp motor. The old TPI 305 was a 190 hp motor with about 285 lb/ft of torque back in 1986 and it sported a heavy flywheel and lets not forget the automatics with their torque converters.

The downside I have experienced personally to date is when my engine idles down very low and starts chopping like a Harley, the dampened flywheel starts to oscillate and transmission noises occur. If it weren't for the flywheel weight it wouldn't be able to idle that low, somewhere around 300 rpm where you could actually count the exhaust pulses, I was amazed.

[Blackrider]

Exactly, inertia between shifts is the trade off. If the engine is producing enough power the added weight will not be much of an issue. It weighs less than some of the V8 flywheels I've encountered including the one used on the 4.3L which I doubt is a 240 hp motor. The old TPI 305 was a 190 hp motor with about 285 lb/ft of torque back in 1986 and it sported a heavy flywheel and lets not forget the automatics with their torque converters.

The downside I have experienced personally to date is when my engine idles down very low and starts chopping like a Harley, the dampened flywheel starts to oscillate and transmission noises occur. If it weren't for the flywheel weight it wouldn't be able to idle that low, somewhere around 300 rpm where you could actually count the exhaust pulses, I was amazed.

Makes sense, my car can run as low 900RPM in gear before it even starts to sputter.

Thanks Joe.