At the end of last year I rebuilt the M20 for my 71 corvette into a M22W using the AutoGear gears. I used the article by Chevy Punch magazine as my guild on disassembling and assembling the transmission. Here is a link to the chevy punch article. I suggest saving it while it is still available. http://www.chevypunch.com/issues/february2007.pdf

Here are my build pics.
This was my original M20 i started with. It had a lot of rust and pitting on the gears. So since I needed to replace them I went with the M22W set.


I ordered a handful or parts including torque lock sliders. I found a lot of the parts through Jody's transmissions. He was also very helpful in the process with any questions I had.


I cleaned up my original case with some degreaser and eventually a brass wire brush.




I proceded to work on the rear case. I installed a new bushing, placed in the reverse spring and the reverse lever. This was a bit tricky keeping that ball down and sliding the lever in.



I then went back to the main case and installed the M22W cluster into the case. You have to do this a few times to get the measurements for endplay and adjust the shims.



With the cluster done, you can go install the bearings and cage into the input shaft. Then I stacked the case on an old case, this way I could put in the input shaft and the reverse idler gears.



Then I went ahead and started pressing everything onto the mainshaft.



It is a little tricky getting the mainshaft into the case. I put the slider down to 4th to catch the input shaft on install. Then wiggled it into place.



The front bearing slides into to place fairly easy with some tapping by a rubber mallet. I then sealed up the front bearing retainer and bolted it in.



Finally I put my side cover back together and onto the transmission. Added the backup switch and poured in some gear oil.

 

Looks good.
What is 1st gear?
How much torque will it handle?
Thanks
Terry

 

The ratios are:
1st 2.559
2nd 1.752
3rd 1.366
4th 1.000

As for torque not really sure on the limit. It should be good for a BBC over 500 hp. For my build the week point would be the case and stock midplate.

 

Thanks for the link. I'm going to attempt this one day.

 

I liked this thread until you showed the type of gear oil being used. Friends don't let friends use Sta Lube! Try some Brad Penn, Amsoil, Lubrication Engineers, or Swepco "MT-1" rated gear oil especially because your running a 22.5 degree M-22 gear pitch now! Even back in the 60's M-22 Vettes had special tags attached to their consoles stating the requirement of special gear oil requirements, that Sta Lube crap isn't a good enough grade of lubricant for a M-22 trans

You just put over $1000 of effort and parts into your Muncie.....now go out and buy a lubricant that will insure that effort lives a decent amount of time.

 

What is the problem with Sta-Lube? It is actually the recommended oil by the gear manufacture and also the builder I got my parts from. You have had people running M22 trans for years with good ole GL-4 gear oil without any issues.

 

Hey it's your money I wouldn't put that lube in a car I owned. I did back when I was a kid running wrecking yard posi stuff at the drags and breaking it on a regular basis ( learned a lot about building differentials and transmissions and lubrication chemistry since then.) I've built 6 M-22 transmissions in my life, the people who bought them were very happy with the performance of them. I wouldn't use Sta Lube except to use as a break in flush on a M-22 trans but, be my guest, I'm probably just some internet troll who probably lost a job at CRC.....

It isn't even the GL4 rating you should be looking for, you need to find a lube with a MT1 rating to prevent degradation of the bronze blocker rings in your Muncie....what's a guy like me know?

 

Nice rebuild Sigforty!

Pardon the hijack...

Solid LT1:

What are your thoughts on Red Line MTL SAE 75W80 API GL-4 (All synthetic and is listed as less slippery for improved synchronizer coefficient of friction.)?

I plan on using it for first fill on a rebuilt BW Super T10. Should I use something different as a break in gear oil and then change to Red Line MTL?

 

Thx for the details. Now could u up grade a Borg Warner T10 for us?

cardo0

 

Never taken one of those apart, but if I ever do I will post up.

 

If your building a trans with a brand new gear set such as this build I would change lube at 500-1000 miles. I'm no longer a fan of Red Line lubes I do have a few gallons of " shock proof " 90-250 gear oil around if anyone is looking for some $50 a gallon! I like Lubrication Engineers 703/704, Swepco, Amsoil and just trying some Brad Penn in a Jeep gearbox this comming week.....looks good so far. You need to use a lubricant with a MT1 rating so it isn't corrosive to your brass Syncro rings of your BW or Muncie.