what is one of the strongest 4 spds out there. i am looking for a 4 spd for a older trans am. what is the strongest one that was a "stock" transmition, that would be able to find

i know that muncie but i know they have a m-22 and some other numbers. i have heard of a super t-10 and a rockcrusher. thanks

 

The M22 is known as the 'toughest' but its not... it was in its day, but the Super T10 of the late '70s was just as strong, if not stronger. Didn't make the car sound like a tractor like the M22 did either. Use the Super T10. Cheaper, stronger, and not as loud.

If you want the strongest factory (although a different factory...) 4-spd though, get an aftermarket bellhousing to mount up a Ford Toploader 4-spd to whatever is in the Trans Am. Those are stronger than any of GM's 4-spd trans.

 

His advice is right on the money. The Super T10 is an excellent 4 speed strengthwise. They're usually a bit cheaper to get your hands on than the Muncies as well. I knew a guy with a 76 T/A that had a 455 and a Super T10. He beat on it pretty hard and the tranny never flinched. The other good thing about them is they came with quite a few different first gear ratios, so you can pick the one that's best for your car. Muncies only came with a 2.20 or 2.52 first gear, both of which require a pretty steep rearend gear for good takeoff (i.e. 3.73 or lower). I personally don't know much about the old Ford toploaders, but even if they are stronger, you'd have to figure out how to adapt one to a GM car.

 

thanks that is the info i wanted. it is going beind a built 400 pontiac. thanks why i wanted a strong trans without going 5 or 6 speed

 

Put a Lenco in it.

 

i don't have the money for a lenco. i bought a trans today. i knew it was a muncie but i cannot find what it is. i am trying to run the part numbers but no one seems to have the ones i have. there are a couple of numbers.


on the side cover it says gm 39200793 6(?)
D 197


on the case it says GM 2
3915032
D 257

if anyone can help i would appreciate it. thanks

 

Is it a fine spline trans (26 spline input shaft)? Theres little else that speparates them visually.. they all use the same case. M20 was a wide ratio, M21 was close ratio, and M22 was close ratio HD.

 

actually it has 10 splines on the input shaft.

 

here are some pics

 

Ummmm, I hate to say it, but it looks like you got taken. If you can get your money back from the guy, I would. That's a Saginaw 4 speed. The fact that it's cast iron and reverse is in the side cover are dead giveaways that it's not a Muncie or Super T10. Both of these trannys have aluminum cases and reverse gear is located in the tailshaft housing, not the side cover. Saginaws are okay, but the Muncies and Super T10's are a lot better units, not to mention that the Saginaws are only worth about $100-$150.

 

Another thing is the older M22's used a 10 spline input shaft also, so that's not a telltale sign either. The earlier ones also had the same 27 spline output shaft as the M21 and M20. Only the newer M22's got the Turbo400 style HD 32 spline output shaft and fine spline input. Earlier models also used a 7/8" countershaft, the newer ones were upgraded to a 1" countershaft. The easiest way to tell the newer M21 and M20's apart are the rings on the input shaft. M21's have one ring, M20's have two rings machined in the input shaft. The best way by far to identify a true M22 is to pull the side cover and look at the gear teeth. M22's have a straighter angle on the gear teeth than the M20 and M21, which makes them unmistakeable once you know the difference. I've messed with Muncies for years. If anyone has any questions about one, feel free to send me a PM. I've got all the casting#'s, gear ratios, etc.

 

well i don't have the strongest trans. but it will get my conversion going. how much power do you think this can handle? i will continue to look for a muncie but for now this should work.

 

Saginaws aren't quite as strong as the Muncie or Super T10, but they're still leagues stronger than the Borg-Warner T5's. They hold up pretty good behind a fairly stout V8.