Does anyone know if a Getrag 282, 5 speed will hold up to a LS364/440 G.M. crate engine? It makes 440hp and 411 ft. lbs. of torque.I would like to put the F40 6 speed in but it might be a hassel.

The Getrag is only rated to about 200 ft lbs of torque. But I have seen them bolted up to big engines and run for a long time with no trouble. Then again, I've seen cases split in half from too much pounding so I guess it all depends on your driving style.

Condition of the transmission is critical. The LS440 is way above the factory rated torque output, so any slop or play in the transmission will make it more prone to failure.
If it's in good shape, though, it should hold up well to regular and spirited driving. I don't recommend clutch dumps, but if you don't abuse it, it should be ok.

The 30# flywheel typically installed with V8 swaps is a vital part of a short transmission life.

Here's some background info on the F40 6-speed transaxle.

2006 F40 (MT2)
Type: transverse front wheel drive, six speed manual transaxle
Engine range: 3.9L
Maximum engine torque: 245 lb-ft ( 333 Nm )
Maximum gearbox torque: 295 lb-ft ( 400 Nm )

Gear ratios:
First: 3.77
Second: 2.04
Third: 1.32
Fourth: 0.95
Fifth: 0.76 Reverse: 3.54
Sixth: 0.62 Final Drive 3.55

V-8 Archie has an install kit for this trans. Check out his site for more details.

I too am looking to put an LS engine in my 1988 GT and I have yet to make a decision as to keeping the 282 5-speed or moving up to the newer and slightly stronger F40. From what I have read on V-8 Archie's site he seems to feel that the 282 5-speed can handle the power of a V-8. But that said he also notes that if you beat on anything long enough and hard enough, eventually you will break it.
I hope the info proves helpful.
Good luck with the project.

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"Its nice to be important.
Its more important to be nice."

Consider cryogenically treating your gears and stress relieving your case. I have my gears out now for cryo treatment and sent the case along for stress relief too. I am also making a ‘girdle” for the right side case to better contain the lateral thrust developed by the ring and pinion gears. Do a search on Getrag failures and you’ll see pictures of cases blown out on the right side. You’ll also read mentions of guys having right side axles push out of the case. You can also use a forged differential from a Quad4 trans instead of the cast one that comes in our Fieros. Searching the cryo bit and the Quad4 topics will yield you some useful threads. All this work may just cause the failure to happen elsewhere though?
You could also consider a Northstar….less weight, less damaging torque, and you still have a modern V8, but yes, sadley less Hp too. There’s lots of support out there now due to the number of transplants. Just few ideas (without intending to start and engine debate)……

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Daviero - 88 N* GT

is there a good reason nobody ever considers the 284 getreg 5 speeds for these v8 swaps? they have a higher TQ/HP rating than the 282s and they have an intermediate driveshaft that venly distributes the TQ to both wheels..aside from early nineties luminas and montecarlos, what other vehicles were they found on?

Grand Prix 91

quote Originally posted by FieroBobo: Will, Would you please elaborate on the 30# flywheel, and why it can cause transmission failure. I am considering putting a V-8 in my car and I'd like to know what the potential pitfalls of this type of a swap are. Thank you Sir.

Anything that contributes to shock loading the transmission will contribute to transmission failure: heavy flywheel + grabby clutch, sticky tires, solid powertrain mounts, etc.
When you launch hard or shift hard, the flywhee has to change speed rapidly. The rapid change in angular momentum of the flywheel mass (more correctly: moment of inertia) causes a torque spike through the drivetrain. Go search the internet for dyno charts of automatic transmission cars. You'll see that on the shifts they can spike the torque more than 100 ftlbs above and beyond the engine's peak output. This is because the shift spins down the rotating mass of the engine and torque convertor. The situation is worse with a stickshift because the spin-down happens in a much shorter amount of time. This is why you can chirp the tires with a hard shift...
Solid powertrain mounts do not allow deflection of the powertrain and thus give the energy in the flywheel no where to go except through the transmission. Compliant (NOT loose or floppy) powertrain mounts absorb some of the initial torque hit from the flywheel and feed that back into the powertrain as they spring back, which reduces the magnitude of the torque spike.

Because, as was mentioned above, the most common failure mode of the 282 is breaking the right diff bearing boss from too much axial loading on the final drive mesh, and because axial loading is proportional to torque, the way to keep the transmission alive is to keep the torque spikes down.

quote Originally posted by aaronrus: is there a good reason nobody ever considers the 284 getreg 5 speeds for these v8 swaps? they have a higher TQ/HP rating than the 282s and they have an intermediate driveshaft that venly distributes the TQ to both wheels..aside from early nineties luminas and montecarlos, what other vehicles were they found on?

Because the 284 is about as common as a hen's tooth and, doorstep to doorstep, will cost $2000 to overhaul.
The intermediate shaft has no affect on torque distribution in a Fiero. You can put an intermediate shaft on a 282 as well.

[This message has been edited by Will (edited 12-28-2007).]

build a strong getrag, treat it right and you will be surprised at how much it will hold up to:

-start with a stock fiero getrag
-buy a differential assembly from a 1992-94 FWD GM transmission (came in caviliers, pontiac 6000s, etc), these have MUCH stronger spider gears which is the fail point in stock fiero getrags.
-buy a LSD assembly or locker for better straight line traction (no wheel spin then instant hook which puts huge shock loads on your tranny)
-cryo treat everything, if you cant afford the case that is the least of your needs, you can skip it if you sdont have the money (~$5/lb)
-DO NOT cryo treat your CV axles, you will want these to be your weak link, they are very cheep (in comparison), they are very easy to replace and all-in-all the best thing that you could break in your drivetrain.
-this is contraversial but if you want to put big power to the ground and not blow up your tranny, I would get a spec IV (solid hub design) and put a weak pressure plate on it... like a RAM or something slightly stiffer then stock but not as much as what Spec gives you. you will get slightly less clutch life if you do this but it will 'give' just enough to not grenade your new tranny that you just stuck all of this work and money into.

please comment if you feel the need to but this is what I believe to be the ultimate street/strip fiero getrag. I can get more in-depth with a drag strip only 5-speed if you would like but I think you are looking for something to drive on the street aswell.

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1987 Pontiac Fiero GT
SBC dual stage Nitrous injected

What experiences do you have with running such a setup?

I think that reduction of MOI and powertrain mounting with controlled compliance are the big goals and when achieved those two factors will allow the use of sticky tires, grabby clutch, etc without problem.

well, I currently have everything done to my tranny that I posted above except a lighter pressure plate which I am going to do this winter when I switch engines. I just found another thread here today that showed a great picture of how to lighten Archie's flywheel drastically. I am going to get more information on this but if I can cut the weight of the flywheel from ~30lbs to 20lbs or less that would even out the clutch disk wear that has been a problem for sbc guys running spec clutches for ever. the spec clutches always wear a lot on the flywheel side and not so much on the pressure plate side because of all the rotating mass that keeps the flywheel spinning.

The light pressure plate with grabby clutch disk was actually taken from VWs where they throw massive hp at trannys that are only rated for 60ft/lbs they found that if you throw a big pressure plate at it the trannys will explode quicker then a cat can lick its a$$. the light pressure plate absorbs a lot of the initial shock but the clutch disk holds enough to keep the power going to the ground after the initial hit is relieved.

I know that I am new hear but I have followed you guys for a long time and for whatever reason decided to join a few weeks ago. so, I hope everything goes good here and I can become a welcomed member of the PFF family, thanks.

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1987 Pontiac Fiero GT
SBC dual stage Nitrous injected
built 5-speed getrag

Richlo, What lsd are you using?? Would that not replace the spider gears?

nope, lockers and LSD units dont replace the spider gears, they are just ways of evening out the power given to each wheel, the spider gears still have to take the brute force of the engine. LSDs push against the surfaces of the spider gears to slow how much each side can spin compared to the other side. Phantom Grips use 2 plates to push against the biggest set of spider gears with 4 friction points total. Gr8Grip uses 4 plates to push against all spider gears with 8 pressure points total. I have a Gr8Grip installed in my tranny with the bigger 92-94 differential assembly, I just sent the whole diff to Bud (owns Gr8Grip) and he sent it back coplete with the new LSD installed, completely painless for me and he is VERY accurate and knowledgeable with his product. I highly recomend him for LSD units.

just remember, if you do get a clutch style LSD unit installed in ANY manual tranny that has the diff inside the transmission you have to get special "Friction Modified Syncromesh" from any GM dealership. Be sure to ask for "Friction Modified" syncromesh otherwise you can run the risk of chewing up your spider gears and your LSD unit and scraping your tranny.

again, I can go more in detail with drag strip only transmissions and differantials with this post but I figure you are looking for something that can still be driven on the street.

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1987 Pontiac Fiero GT
SBC dual stage Nitrous injected
built 5-speed getrag

quote Originally posted by Will: Because the 284 is about as common as a hen's tooth and, doorstep to doorstep, will cost $2000 to overhaul. The intermediate shaft has no affect on torque distribution in a Fiero. You can put an intermediate shaft on a 282 as well.

does the 284 have the same gearing as the 282? if not, what is the gearing for the 284. also, what is the rated strength of the 284 tranny?

I hear numbers tossed about like 200 ftlbs for the 282 and 250 for the 284. I forget whether GM's designations were 5TM40 for the 282 or 284...

The Fiero 282 had 3.50, 2.05, 1.38, 0.92, 0.72 with 3.61 final.
The 284 has 3.46, 2.28, 1.43, 1.03, 0.72 with 3.67 final. It's geared for a bigger engine, with more even splits across the rev range.

But 1st gear is still WAY too low.

quote Originally posted by Will: I hear numbers tossed about like 200 ftlbs for the 282 and 250 for the 284. I forget whether GM's designations were 5TM40 for the 282 or 284... The Fiero 282 had 3.50, 2.05, 1.38, 0.92, 0.72 with 3.61 final. The 284 has 3.46, 2.28, 1.43, 1.03, 0.72 with 3.67 final. It's geared for a bigger engine, with more even splits across the rev range. But 1st gear is still WAY too low.

damnit.. if only someone could manufacture a higher geared final, somewhere in the 2.83:1-3.06:1 range...i was hoping you would say the 284 had better gearing for a v8, but it doesnt apparently..

quote Originally posted by aaronrus: is there a good reason nobody ever considers the 284 getreg 5 speeds for these v8 swaps? they have a higher TQ/HP rating than the 282s and they have an intermediate driveshaft that venly distributes the TQ to both wheels..aside from early nineties luminas and montecarlos, what other vehicles were they found on?

Yea, they are nice but they are pretty rare and not too many people know that there is a difference. In fact, wasnt the LQ1 (3.4 DOHC) detuned because GM couldnt make the 284 strong enough?

What is the way to identify the difference between the 282 and 284 externally ( serial number or something else )
I have a FWD getrag suposedly coming out of a 1991 Grand Prix but not sure ? And there is no digit on the casting anywhere . here are a few pics



there was no thread in these 2 holes

quote Originally posted by Robert 2: What is the way to identify the difference between the 282 and 284 externally ( serial number or something else ) I have a FWD getrag suposedly coming out of a 1991 Grand Prix but not sure ? And there is no digit on the casting anywhere . here are a few pics

you have a 284. but if its out of a 1991, you still have the smaller spider gears in your diff. if you plan on running the stock fiero speedometer you will have a problem because of the speedo gear insided there. my 92-94 diff (Im not exactly sure which year it was, and I dont really care) came with that steel cross-cut speedo gear also like yours in the pic above and I just poped that one off and popped the old fiero plastic heli-cut speedo gear onto it while it was out and now I can run a stock fiero speedo and speed sensor without any more modifications... the gear was a direct fit replacement. You might have to get a speed sensor from a 284 car and adapt it to the fiero.

you might have a 92-94 also, I would write those casting numbers down and spend some time searching for a getrag casting number referance chart on the internet (google, yahoo) to see what you actually have since your not to sure and there was a BIG differance from the 1991 year to 1992.

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1987 Pontiac Fiero GT
SBC dual stage Nitrous injected
built 5-speed getrag

Hi and thank you
I have the plastic gear that i bought from Rodney Dickman .
I'm suppose to open the tranny to put it in but i'm a little bit scary with that .
As far as the casting number i can't find one anywhere on the tranny ??? Only had the sticker from where it was rebuilded .
but now the sticker is gone .
Don't know if the number on it can lead us to something positive ( the one on one of those pics above )
Can you tell me where is the dif from the 282 -284 just by looking at it ( mean something you can point at )

quote Originally posted by Robert 2: What is the way to identify the difference between the 282 and 284 externally ( serial number or something else ) I have a FWD getrag suposedly coming out of a 1991 Grand Prix but not sure ? And there is no digit on the casting anywhere . here are a few pics

I don't know what the other guy's smoking, (or if that's just a typo) but this is a 282.
The 284 takes a pull-to-release clutch and has a significantly different bellhousing and throw out mechanism.
The other data about the diff gears is pretty much correct (for a 282).

The ONLY way you will get a 284 is out of a 91-93 Grand Pric GTP, Olds Cutlass International (?), or Lumina Z34. These cars had the 3.4 TDC engine. Nothing with a 3.1 ever got the 284.

[This message has been edited by Will (edited 12-30-2007).]