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Discussion Starter · #1 ·
So for shits and giggles, I decided to open up the muncie that came with my car. I knew it was going to need a rebuild, but I wasnt really counting on this. I will preface this by saying that I know nothing about these transmissions. I was going to get a rebuild kit and book from 5speeds.com and just work my way through it. I couldn't tell what gears were grenaded, but broken chunks of metal in a transmission is never a good sign. Also noticed that there is a hairline crack in one of the mounting ears.




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Discussion Starter · #3 ·
Yikes....there's a good story behind that one.
Probably. Unfortunately, I was not part of it. Im still hoping this is rebuildable, but I dont have my hopes too high for that. Im not even sure I would rebuild this case with the cracked ear.
 

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It appears that one of the sliders let go. If it was rebuilt prior these may have been replaced. Possibly with the cheap Chinese knockoff sliders that are not nearly as dependable as original. Without having more detailed pictures of the gears/counter gear it’s hard to say if they’re salvageable. Everything is usually rebuildable but with the cracked case it may be cheaper to source another one? Unless it’s numbers matching?
 

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Discussion Starter · #5 ·
It appears that one of the sliders let go. If it was rebuilt prior these may have been replaced. Possibly with the cheap Chinese knockoff sliders that are not nearly as dependable as original.
Heres a few pics of what I pulled out of the case. Dont know what they are. Most likely not a rebuild with chinese parts, since best guess is this thing hasnt run in 25-30 years. Of course, nothing would surprise me and for all I know this transmission was sitting in the barn with the car and they threw it in there when they sold it.

Not a numbers matching case, so no worries there. Also, I have a good friend who is a master welder and would be able to weld the ear if need be.

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Probably. Unfortunately, I was not part of it. Im still hoping this is rebuildable, but I dont have my hopes too high for that. Im not even sure I would rebuild this case with the cracked ear.
My question to you is, is your car going to be a stock rebuild? If you plan on building your engine for more HP/TQ, then I would not put a dime into the trans - unless you want to have a repeat after you rebuild it. If you plan on building up more HP/TQ, then I would go with a heavier transmission that will hold up, and now might be the time to upgrade. (y)
 

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Discussion Starter · #7 ·
My question to you is, is your car going to be a stock rebuild? If you plan on building your engine for more HP/TQ, then I would not put a dime into the trans - unless you want to have a repeat after you rebuild it. If you plan on building up more HP/TQ, then I would go with a heavier transmission that will hold up, and now might be the time to upgrade. (y)
Are you saying an M-22 or something like a tremek 5 speed?

As far as what I want to do HP wise, I dont really know. Realistically, I am at least 2 years away from that. I might change my mind 10 times between now and then. Right now, a healthy 400 or 455 would be nice. But if this muncie was blown up by the current motor, it makes me wonder what the previous owner did to this motor. Maybe ill take it apart during the winter and see what it looks like.
 

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Are you saying an M-22 or something like a tremek 5 speed?

As far as what I want to do HP wise, I dont really know. Realistically, I am at least 2 years away from that. I might change my mind 10 times between now and then. Right now, a healthy 400 or 455 would be nice. But if this muncie was blown up by the current motor, it makes me wonder what the previous owner did to this motor. Maybe ill take it apart during the winter and see what it looks like.
Yes, something that can handle more HP/TQ if you go that route. You can destroy/damage a Muncie with stock HP just as you can the 10-bot rear end - just depends on how you use your car.
 

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The slider let loose it appears and subsequently sent those parts through the transmission. Personally I’d start looking for a replacement. Being that it’s not #’s matching and the crack in the case ear. By the time you start adding up case repair, gear set (Italian only! No Chinese gears), sliders, bearings, synchros, gaskets, etc. you’ll easily be in it more than what you can find a replacement for, usually 1-1.5k. Or if you want to take a chance with it you can pull it apart, profile the gear teeth as best as possible, put a rebuild kit in it for about 300 bucks, a new slider for about $40 and run the crap out of it.
 

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So for shits and giggles, I decided to open up the muncie that came with my car. I knew it was going to need a rebuild, but I wasnt really counting on this. I will preface this by saying that I know nothing about these transmissions. I was going to get a rebuild kit and book from 5speeds.com and just work my way through it. I couldn't tell what gears were grenaded, but broken chunks of metal in a transmission is never a good sign. Also noticed that there is a hairline crack in one of the mounting ears.




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The munci in my day was called a "munchie" because they were good for a couple months of weekend hotrodding. Try the T10 easy to build and very strong.
 

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Unless you’re throwing a lot more power at it I would stick with the Muncie. This is probably what the car came with and for most, when you resale it that’s what most expect in it. They’re not that expensive to replace and with a steel mid plate installed are pretty reliable with stock/mild torque applications. If you have an issue finding one local there is an older gentleman in Southern Utah that has bought Muncie’s up for years, rebuilds them and sells them pretty reasonable. PM me if you’d like his info.
 

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Discussion Starter · #13 ·
In the next installment of "What else could go wrong", I decided to pop the cover off the rear to check out the gears.

Ok, ring gear looks OK....(dont mind the hair and fuzz from my rag)

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Lets spin it and see what it looks like...oh no...

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Turns out my pinion gear is chipped in a few spots. There was no metal in the gear oil, so this had been taken apart and most likely just cleaned out and put back together at some point. I also noticed a while ago that one of the upper control arm mounting ears was welded. That didnt necessarily bother me, but at this point I dont know if this rear is even worth rebuilding. I mean, I would like to find the previous owner and give him a swift kick in the ass. The more I see, the more I realize that this car was just rode hard and put away wet...
 

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In the next installment of "What else could go wrong", I decided to pop the cover off the rear to check out the gears.

Ok, ring gear looks OK....(dont mind the hair and fuzz from my rag)

View attachment 145726


Lets spin it and see what it looks like...oh no...

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Turns out my pinion gear is chipped in a few spots. There was no metal in the gear oil, so this had been taken apart and most likely just cleaned out and put back together at some point. I also noticed a while ago that one of the upper control arm mounting ears was welded. That didnt necessarily bother me, but at this point I dont know if this rear is even worth rebuilding. I mean, I would like to find the previous owner and give him a swift kick in the ass. The more I see, the more I realize that this car was just rode hard and put away wet...
Well, you now have a good excuse to go with a Tremec TKO 5-speed with OD and a Ford 9" with 3.73 or 3.89 gearing. Both should be bullet proof and then you will have an excuse to build a 500HP stroker engine.

I would also be looking at the frame for cracks. Check where things bolt to the frame like the upper control arms and the crossmember. Previous owner might have been drag racing the car with wide sticky slicks. Are your quarter panels straight? If you see any buckles or distortions - the car was drag raced hard.
 

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Discussion Starter · #15 ·
I would also be looking at the frame for cracks. Check where things bolt to the frame like the upper control arms and the crossmember. Previous owner might have been drag racing the car with wide sticky slicks. Are your quarter panels straight? If you see any buckles or distortions - the car was drag raced hard.
I did check out the frame and did not see any cracked welds or anything like that. It is a convertible, so the frame is a little stronger than a non-boxed frame. Of course, I do not have the car off the frame yet, so who knows what I will see when I do that...
 

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Discussion Starter · #16 ·
Im heading to Carlisle and Hershey in a few weeks. Im going to look for another 8.2 I think. What I think I want with this car is something that cruises nice, sounds good, is reliable and can smoke the tires when necessary. While a 9 inch conversion sounds nice, right now thats money that I can use elsewhere...like a new Muncie.
 

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I think it’s a great time to go to 3:36 gears for cruising with a posi and throw the new Muncie in there! But Jim’s idea is also very enticing.
 

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Discussion Starter · #18 ·
I think it’s a great time to go to 3:36 gears for cruising with a posi and throw the new Muncie in there! But Jim’s idea is also very enticing.
Hopefully Ill find one at Carlisle or Hershey. Along with an M20.😀
 

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Discussion Starter · #19 ·
I found a gentleman selling an m20 at a fair price. The trans was rebuilt about 20 years ago and never used. It was previously in his 65 GTO. Has a 1" input shaft and 11/8" output shaft. It does not have rings on the input shaft. Would this fit my 66, and would the lack of rings indicate a weaker input shaft, or are they all the same?
 

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Some of the early (I believe 63-65) Muncie trans had no rings. The other being the M22. I would be suspect that the counter shaft may have been machined out to a 1”. I would measure both shafts and verify the spline count against your current. And of course open up the trans and inspect it for corrosion.
 
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