Inquiring minds want to know. We are about 1 year out from the first swaps I can find of this trans behind some 3800's and some V8's. I'm curious if anyone has managed to blow one up yet.

No need to discuss gear ratios, clutches, fittament, old flame wars, etc as all of those things have been discussed in other places already. I'd like to hear from anyone who's managed to break this trans in their high HP application, and if you can include what your setup is as well, that much better.

cheers,
Sabooo

I want to know too,
If you post "I didnt break it" add how you tried, do you drive it hard, launch, etc
and how much power are you trying with, doesnt count if you never get on it.

I know of at least one

quote Originally posted by sabooo: Inquiring minds want to know. We are about 1 year out from the first swaps I can find of this trans behind some 3800's and some V8's. I'm curious if anyone has managed to blow one up yet. No need to discuss gear ratios, clutches, fittament, old flame wars, etc as all of those things have been discussed in other places already. I'd like to hear from anyone who's managed to break this trans in their high HP application, and if you can include what your setup is as well, that much better. cheers, Sabooo

The 6 speed has not been R/D to it full potential by anyone that I have seen. The only advantage of the 6 speed is that it is new but being there are new 4/5 speeds for sale that are stock for the Fiero, it kinda kills that reason to go with a 6 speed.

I am leaning torward a 6 speed swap on a 3800SC just to say I did it and see what it is like. If this happens then I will do everything I can to tear it up to see what it can handle.

If Troy ever gets his Perfect Onion out of Archie's shop, maybe his modified LS7 will break it.

Hmm, I didn't know anyone with a 6 speed drove their car hard on a regular basis...

quote Originally posted by jscott1: I know of at least one

inquiring minds want to know

quote Originally posted by Jncomutt: Hmm, I didn't know anyone with a 6 speed drove their car hard on a regular basis...

BINGO!!!!!!!!!!!!!!!!!!!!!!

quote Originally posted by BMTFIERO: inquiring minds want to know

I don't know the history behind this, because it's not mine, but I'm pretty sure it didn't come from the factory this way:

well, you know, an auto wouldn't do that

quote Originally posted by jscott1: I don't know the history behind this, because it's not mine, but I'm pretty sure it didn't come from the factory this way:

Nice! Wish I knew the story behind that.

quote Originally posted by jscott1: I don't know the history behind this, because it's not mine, but I'm pretty sure it didn't come from the factory this way:

Wow, that's an old one.

You must have seen that one when you were at the shop picking up or dropping off your car. Or whoever took the picture saw it at the shop. whoever took the pic should have asked about it & I could have shown them what happened.

That trans didn't break from the inside out. The inside is just fine. It was cracked from the outside by a key on a computer keyboard.

A few years ago I ordered a set of Axles for the then new G6 conversions. When I was typing up the Purchase Order, I hit the wrong key on the PC & made the left side axle 1" shorter than I had intended. Some time later as the car was being driven in a parking lot (low speed) the inboard Tripot broke. The axle then whipped around & cracked the case.

Later, rather than throw it away, we cut some more of the case away so we now use it as a show & tell pc.

My Grandkids love it, they like to turn the imput shaft & run the shift levers & see it all move around inside.

Archie

BTW, I'm editing this to add this......

My background has a 9 year stint as a QA Manager in Aircraft Manufacturing.

Whenever an error like this happened we would make whoever did it fill out a Cause & Corrective Action Report. This form would explain what happened & what was done to improve the QA system to make sure it didn't happen again.

Now all my P.O.'s are compared to previous P.O.'s for the same item.

We no longer allow the axles to be assembled by a vendor before they are delivered to us for inspection & inspections are logged.

After a 6 speed car is assembled & on the floor we have what we call a "Push in" measurement that is taken of the final assembly & we log those numbers.

A

[This message has been edited by Archie (edited 05-02-2009).]

And now I do..

quote Originally posted by Archie: Wow, that's an old one. You must have seen that one when you were at the shop picking up or dropping off your car. Or whoever took the picture saw it at the shop. whoever took the pic should have asked about it & I could have shown them what happened. A

Thanks for the history...yeah I saw that years ago, but I wasn't trying to "out" you or anything. I figured it broke one way or another, so it's not made out of unubtanium or some other such unbreakable metal.

quote Originally posted by Archie: Wow, that's an old one. You must have seen that one when you were at the shop picking up or dropping off your car. Or whoever took the picture saw it at the shop. whoever took the pic should have asked about it & I could have shown them what happened. That trans didn't break from the inside out. The inside is just fine. It was cracked from the outside by a key on a computer keyboard. A few years ago I ordered a set of Axles for the then new G6 conversions. When I was typing up the Purchase Order, I hit the wrong key on the PC & made the left side axle 1" shorter than I had intended. Some time later as the car was being driven in a parking lot (low speed) the inboard Tripot broke. The axle then whipped around & cracked the case. Later, rather than throw it away, we cut some more of the case away so we now use it as a show & tell pc. My Grandkids love it, they like to turn the imput shaft & run the shift levers & see it all move around inside. Archie BTW, I'm editing this to add this...... My background has a 9 year stint as a QA Manager in Aircraft Manufacturing. Whenever an error like this happened we would make whoever did it fill out a Cause & Corrective Action Report. This form would explain what happened & what was done to improve the QA system to make sure it didn't happen again. Now all my P.O.'s are compared to previous P.O.'s for the same item. We no longer allow the axles to be assembled by a vendor before they are delivered to us for inspection & inspections are logged. After a 6 speed car is assembled & on the floor we have what we call a "Push in" measurement that is taken of the final assembly & we log those numbers. A

I was wondering what was up wth that photo ..the gears looked fine ...

quote Originally posted by jscott1: Thanks for the history...yeah I saw that years ago, but I wasn't trying to "out" you or anything. I figured it broke one way or another, so it's not made out of unubtanium or some other such unbreakable metal.

No problem Dude. That trans. has been sitting around in plain view for a long time.

Until you posted about it, it never occured to me that people might have seen it sitting around & thought that it had been blown up. I should attach a note to it for people that see it in the future.

At first it was just sitting around. Then when Troy wanted his trans. case Chrome Plated, I was checking out Chrome plating businesses that i was thinking about using. I cut a few pcs. out of the trans case as test pcs. to find a supplier that could do a good job. A couple of potential suppliers failed when they screwed up the plating on pcs. of this trans.

From there it developed into a "cut-away" trans. It now has a chunk of the bellhousing cut-out so we can use it to mock-up different clutches for clearances on different engines.

Archie

There are a fair number of people on this forum that are diehard fans of the manual. We also have a group of people that absolutletly want the superior strength that the automatic offers. The manual group feels that driving an auto is boring and the auto group wants fast shifting and reliability. The bottom line is the available stick chocies are limited and can only provide so much strength. However, the SS Cobalt w the 260HP Ecotec is available with a stick but a traction control system is also used with it.
Right now the solution seems to be to avoid hole shots, using slicks, drag radials, and keeping the 1/4 mile runs limited but if someone can figure out how to deploy a traction control system that may provide the ultimate fix..

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, 3.4" Pulley, N* TB, LS1 MAF, Flotech Exhaust Autolite 104's Custom CAI 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

This is the trans pictured above. I have many others but don't ask. Sore subject to this day with the wife.

[This message has been edited by LT188GT (edited 05-02-2009).]

I'm getting off topic, so please forgive, but I hafta ask, Archie, please give us a tooth count on that differential gear, is it 78 or 71 tooth?
If it's 78 then the final is 3.54545:1, but if it's 71 then it's 3.55000:1. Thanks!

This might help.


http://www.fastfieros.com/N...nsmission_ratios.htm

thank you, but I've seen it before, it doesn't have the answer, or I wouldn't have asked. I have all the other MT2 ratios to 4 decimal places, but not the final. And my apologies that this is getting even farther off topic.

quote Originally posted by Isolde: thank you, but I've seen it before, it doesn't have the answer, or I wouldn't have asked. I have all the other MT2 ratios to 4 decimal places, but not the final. And my apologies that this is getting even farther off topic.

I'll get a count for you tomorrow when I go over to the shop.

A

quote Originally posted by Dennis LaGrua: There are a fair number of people on this forum that are diehard fans of the manual.

Yeah, I'm pretty die hard manual... I have 4 speed, 5 speed and 6 speed Fieros. But my 4.9 doesn't have enough torque to break the F40 so it's ideal for me. If I had a more powerful engine like an LSx and were wanting to drag race, I would be forced to go auto. But LSx and drag racing is not in my immediate future.

quote Originally posted by Isolde: I'm getting off topic, so please forgive, but I hafta ask, Archie, please give us a tooth count on that differential gear, is it 78 or 71 tooth? If it's 78 then the final is 3.54545:1, but if it's 71 then it's 3.55000:1. Thanks!

78 Teeth

Archie

Archie is my new best friend. Thanks a million!

quote Originally posted by LT188GT: This is the trans pictured above. I have many others but don't ask. Sore subject to this day with the wife.

Wow, you broke the tri-pot (or is it a tulip)... I'm guessing that you were scaring the wife with some serious acceleration when this happened.

Say, are those billet or cast? Casting defects are common and would explain why it just cracked and blew.

[This message has been edited by Rolling Thunder (edited 05-04-2009).]

Archie explained above what happened. Axle was too short, came apart, and whipped the side of the transmission.

quote Originally posted by Isolde: Archie is my new best friend. Thanks a million!

He's not my best friend, but he did just get a plus from me for taking the time to count those teeth.

I think I'll be building a guard for mine, even with correct axle length.

quote Originally posted by Jncomutt: Hmm, I didn't know anyone with a 6 speed drove their car hard on a regular basis...

Wrong. I drive my car like I stole it every day. It's only been on the road for a year but i haven't had any problems yet. I race my car at autocrosses just about every other weekend and drive it just as hard on the street. I'm only makeing 305 rwhp and 310 ft lbs of torque at the moment but it's not exactly peanuts.

I'll try to break mine one of these days. Don't want the spare to rust.

------------------

Red: TPI V8 + 6-Speed Yellow: Nitrous 3.4 + 4 speed Auto
304rwHP/366rwTQ

quote Originally posted by Zac88GT: I drive my car like I stole it every day.

This is my goal, and my motivation for asking. I am hoping to put something in that will suffer a bit of abuse. I have had an eye out for posts about breaking this trans, but I haven't seen any. The folks I've talked to seem to all be doing fine in regards to this swap.

I just found this thread on the Daewoo forum: http://www.daewootech.com/f...?f=3&t=6502&start=45

Looks like someone swapped one into an '04 GP, running 18 psi on a T66 turbo, and broke 2 F40s in the exact same way.
Couple of pics, and I think it was the stock trans, without cryo or anything.

Behold the almighty F40!

Interesting.

Didn't GM redesign that trans after the 1st year's production?
Seems like there was a surplus of the 1st design on eBay for a while.

People speculated that it was for a ratio change (the redesign did have different ratios) but I wonder if GM knew about 2nd gear being the "fuse".

quote Originally posted by Raydar: Interesting. Didn't GM redesign that trans after the 1st year's production? Seems like there was a surplus of the 1st design on eBay for a while. People speculated that it was for a ratio change (the redesign did have different ratios) but I wonder if GM knew about 2nd gear being the "fuse".

No. The MT2 was in use since 2003 in Saab vehicles, I believe. It was changed in 07 (the rpo is different, MT2 is the older version, MU9 is the newer one). There were some gear ratio changes, as well as I believe, a change in the detent on the shift sleeve, with some increased tension between the sleeve and rail, to prevent vibrating while in gear. I don't know if there were any strength changes as far as the case goes, or if the gear materials are stronger or not.

It would be interesting to know if the detent/sleeve changes are adaptable to the MT2 also, to help reduce any vibration in the trans. Pretty sure I'll be taking my trans to get cryo treated now though.

So before the guy was fragging fully built 4T65e and now he is fragging the F40... with 581 whp through the 4T65.... or about 700+ crank hp and a redline of 6200 rpm... With that low of a redline, he would be making around 700+ lb-ft of tq (flywheel)...

He most certainly has a monster setup and probably needs to perform a driver mod... or drop 15K on a tranny that will hold that kind of power.

[This message has been edited by fieroguru (edited 07-27-2010).]

quote Originally posted by fieroguru: So before the guy was fragging fully built 4T65e-HD's and now he is fragging the F40... with 581 whp through the 4T65.... or about 700+ crank hp and a redline of 6200 rpm... With that low of a redline, he would be making around 700+ lb-ft of tq (flywheel)... He most certainly has a monster setup and probably needs to perform a driver mod... or drop 15K on a tranny that will hold that kind of power.

Justin never legitimately broke his transmission.

edit

quote He was running 18psi on a T66, headwork, cam, 3" straight exhaust, triple disc clutch

That is not that amazing. 18psi on pump gas and a little 3 inch exhaust is not anything to blow up any trans over. Maybe 430whp through an auto, so, no more than 510 or 520whp on the manual, which both Justin and John have been putting down on their fieros without transmission related failures (just spec clutch failures).

Would be interesting to see where that guy got a triple disk clutch from.

[This message has been edited by darkhorizon (edited 07-27-2010).]

quote Originally posted by darkhorizon: Justin never legitimately broke his transmission. I would say that any single disk clutch that guy could have in there wouldnt grab enough to break a 282.

The thread says he is running a tripple disk clutch... there is room in the F40 for such animal, but it would not be street friendly as all and could be a possible contributor to the failures.

Curious what has happened in the last year?

[This message has been edited by fieroguru (edited 07-27-2010).]

quote Originally posted by darkhorizon: That is not that amazing. 18psi on pump gas and a little 3 inch exhaust is not anything to blow up any trans over. Maybe 430whp through an auto, so, no more than 510 or 520whp on the manual, which both Justin and John have been putting down on their fieros without transmission related failures (just spec clutch failures).

I'm not saying it is amazing. But the post also doesn't say what engine is getting that boost. I was just restating what was said in the thread, and pointing out that he broke a trans. Troyboy is putting out about 480whp through an F40 with no problems, but his is also cryoed.

I don't know what the reference to blowing up the autos, that fieroguru made, was about. I didn't see that in that thread. Maybe he knows the guy from another forum or something, where he was complaining about it.

But this guy with the GP broke the trans twice doing the exact same thing, so it would be nice to know what exactly caused it. If it's the insane clutch, shifting at readline, and causing the rpm drop to put it right at the peak torque area when he lets out of the clutch, increased load, or something else. It's a thread about whether the trans has broken for anyone, and I figured people might want to see one broken. More info would be great, but I don't have any more.