Technical Either broke my M20 or damaged the clutch seriously

this is simple, if in neutral and clutch pedal is out, all gears are turning. Input shaft, cluster and all gears on main shaft. None of the gears are engaged by the sycro hubs. It is called a constant mesh transmission. When in first gear, the power goes from the input to the cluster gear and then to rear of transmission where firs gear is. Second gear is the same but engages the second gear forward on the main shaft. Third moves forward again on the cluster and main shaft and fourth is a lock up between the input and main shaft. If in neutral. and clutch out and makes noise, you have broken something inside the gear box as it is hard to shift as you said. If clutch is in there is no part of gear box spinning including the input shaft and clutch disc. If it is noisy at this time, you have a clutch disc/ pressure plate/ throwout bearing problem. If the noise is worse with clutch out, then you may have two things wrong. If the input shaft is broken where it engages at the cluster gear, you will not have first second or third, just 4 or high gear. i think you have a couple problems here caused at the same time. good luck.

 

Nah... looked at the vitals and the oil pressure was good, got home and nothing dripping that wasn't dripping before.

 

I was thinking my issue is compound. I'll know something more before the evening is out. Hot and sticky here and my allergies are bad...

 

here too, pic taken this afternoon with my 32 with a very accurate vintage temperature mirror...90-91..headed to the scrapyard looking for cool chit!

there were snow flurries in northern Connecticut, 2 -3 days ago! 44 degrees yesterday morning..


hey, run skinny rear bias, cut 5 feet off the back of that 59...and burn rubber right the 'ell across Long Island...lol.. without breaking anything..

The Chicks don't care how quick it is off the line! They want a show, Dude!! LMAO

 

I am betting one of the springs in the clutch disc fell out... will cause a noise at all times and will prevent the clutch from disengaging, causing the hard to shift.

 

my bet is most of one tooth is missing on the input shaft, and or, the forward-most gear on the cluster.

 

It's the jets, man..

 

The verdict.. blowed up to some extent. Clutch works fine. Clutch in... quiet as a mouse. Clutch out... a bucket of bolts. Out it comes on Saturday and will take pictures. Every crime scene needs to be documented.

 

That's where my $$ is. I did have 1st gear so the countershaft gears is somewhat intact.

 

Love me some CSI

 

Carnage. Never nice.

 

Ain't so bad when its' some one else's...

 

I had a OT car with a 396/ 375hp engine with the 10.5" L88 lightweight flywheel, and matching clutch & pressure plate from the local Chevy Dealer. I was using a Lakewood scatter shield & a Muncie 4 speed. Sometimes shifting at 7000 rpm, it would not go into gear. I found out the diaphragm pressure plate was going over center causing the problem. Mr. Gasket made a bracket that bolted to the clutch lever inside the car. It was ajustable to limit the stroke of the pedal to keep the pressure plate from over centering making for much better shifting!!!!!!!!!!!!!!!!!!

 

Could have been worse, at least I limped home with it and the clutch is good. The PP is balanced to the flywheel and I'd hate to have that done again. This is the first thing I have broken in many years and the $$ end is the least of it.. I can't jump in go for a ride for at least a week!

My speedo connection is on the driver-side and sort of in the way of the shift rods. If I go for a wide-ratio '67 and up, this puts the cable on the passenger-side. Easy enough to see if I have enough cable or buy a longer one. But I have to have the 2.56 or 2.52 1st gear.

Possibly looking at a T10 option, I have to see how close it gets to mounting up, don't want to have to play with the driveshaft. My adapter plate on the crossmember is... adaptable.

 

T10 and Muncie are same length, basic same tranny. Output shaft though i think is same as TH400 and Rock crusher. Not the smaller one like yours and Th350/ PG. Just need a front yoke and joint, that's all

 

Pull the side plate and look.

 

Don't we all need a m22.
I have 2--m21's and still want a m22

 

As promised. Yanked it out, was a tough job, got some help for the heavy work. The last time I had it out I was able to leave the crossmember in... this time no luck. Added to the chore.

Looks like the main shaft gear and 1st is wiped out on the cluster. Drained the oil, cleaned up everything and put it away. Will think of a replacement box on Monday. See some new ones at a decent price, I can fix this one at my leisure.

 

Well,now don`t that just suck.
Good luck.Have fun.Be safe.
Leo

 

Looks like it's getting ready to hump a Vette.

 

I later raised the back up too to give more room. Sore as heck today and moving slow. Shopping on line, Muncie... T10... hate to have to change the clutch disc and front yoke. But will if that's where things take me.

 

The old iron case T-10 will be a direct bolt in, same 10 spline input and 27 spline output. Would be pre-1965 I think? What GM used before the Muncie was introduced.

The later ST-10(Super T-10) the aluminum case stuff GM went to in 1975, and iron case Brute Force versions from the same time frame have a 26 spline input and 32 spline(TH-400 size) output.

 

Yes, the Super T10 is different mounting than the pre-1971 Muncie. From what I read so far. I could go M22 for around $300 more, plus a new clutch disc and trans yoke. Auto Gear has a nice M20 for around $1800 and everything is new, case, all gears, etc.

 

You can go with a replacement Muncie M-20 or M-21; M-22 will have the bigger output shaft and fine spline input. Older T-10 will need a course output slip yoke. Newer Super T-10 will need both input disc and output slip yoke. You could go with a Saginaw, depending on the engine you have (I'd skip that idea!). Muncie's and Borg Warner's have VERY similar shifter mounts and linkage; Saginaw will be DIFFERENT (another reason to stay away from). Craig's List time for something locally would be the best bet, unless you're independently wealthy, like me (yeah right!). Take your time, you'll find the right deal; stick with the Muncie. I am Butch/56sedandelivery.

 

So you need an input and a cluster. What else?

 

I don't have it apart, taking it to a local guy to see if he can turn it around in a couple of weeks for a decent price. I'm looking at the Auto Gear M20 for $1775, really the best deal I've seen so far.

 

Got it back last week, had another thread going about where to get a replacement box. A local guy, Larry from D & L Transmissions went through it for me. I now have a later M20 input shaft, new cluster gear, some other worn pieces replaced with good used pieces. The case was bored for a 1" counter shaft pin, the 7/8" pin spun in the case, which takes out the locating ledge on the mid plate. My reverse idler gear should have no worked at all, someone had garbaged my box together using who knows what. Larry was amazed that my pre-crash box shifted so well, it does now down-shift better. The new one is working well, each shift feels a lot better and no noise from it.