4-speed question: M20 or M21????
Thread Starter
Team Owner
Joined: Jul 2001
Posts: 182,997
Likes: 88
From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
4-speed question: M20 or M21????
I just got back from Clearwater (Tampa area). I went there to pick up my old transmission and engine. I tried to check the numbers on the transmission. I looked up all the numbers on the transmission and tried to find out what transmission it is. All the numbers came back that the transmission could be either a M-20 or M-21. How can I find out if my tranny is a M-20 or M-21??? Here are all the numbers from the transmission:
3925660
3884685
3857584
3915020 (below input shaft)
P8T13
Part of my VIN number is also stamped on the transmission...
Does anyone know it it's a M-20 or M-21???
:cheers:
Olivier
3925660
3884685
3857584
3915020 (below input shaft)
P8T13
Part of my VIN number is also stamped on the transmission...
Does anyone know it it's a M-20 or M-21???
:cheers:
Olivier
Safety Car
Joined: Jan 2001
Posts: 4,660
Likes: 3
From: South Central Louisiana
St. Jude Contributor
Re: 4-speed question: M20 or M21???? (GrandSportC3)
p- muncie
8- 68 yr model
t- dec month of production
13- should be day of month
you should have a letter after the 3
8- 68 yr model
t- dec month of production
13- should be day of month
you should have a letter after the 3
Thread Starter
Team Owner
Joined: Jul 2001
Posts: 182,997
Likes: 88
From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Re: 4-speed question: M20 or M21???? (71,454,4spd)
p- muncie
8- 68 yr model
t- dec month of production
13- should be day of month
you should have a letter after the 3
8- 68 yr model
t- dec month of production
13- should be day of month
you should have a letter after the 3
18S407244
How can the transmission have a later date of manufactory than the car???? That's strange! I also looked for an additional letter after "3" but there is no letter....
:cheers:
Olivier
Safety Car
Joined: Jan 2001
Posts: 4,660
Likes: 3
From: South Central Louisiana
St. Jude Contributor
Re: 4-speed question: M20 or M21???? (71,454,4spd)
Take a look at this post, it explains alot. As far as the date confusion, I believe that:
8- the year of car used in not the year the trans was produced. But the month and date is the actual time that the trans was produced. You won't have a letter after the 3, so follow the post to find out if you have the close or wide ratio.
http://forums.corvetteforum.com/zerothread?id=336188
[Modified by 71,454,4spd, 10:40 PM 7/7/2002]
8- the year of car used in not the year the trans was produced. But the month and date is the actual time that the trans was produced. You won't have a letter after the 3, so follow the post to find out if you have the close or wide ratio.
http://forums.corvetteforum.com/zerothread?id=336188
[Modified by 71,454,4spd, 10:40 PM 7/7/2002]
Team Owner
Joined: Jun 2001
Posts: 23,380
Likes: 1,067
From: Virginia USA
Re: 4-speed question: M20 or M21???? (71,454,4spd)
Go here http://www.5speeds.com/index.html
In the navigation box on the left click on Muncie 4 Speeds. This site will tell you everything you want to know.
John
In the navigation box on the left click on Muncie 4 Speeds. This site will tell you everything you want to know.
John
Thread Starter
Team Owner
Joined: Jul 2001
Posts: 182,997
Likes: 88
From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Re: 4-speed question: M20 or M21???? (theandies)
Go here http://www.5speeds.com/index.html
In the navigation box on the left click on Muncie 4 Speeds. This site will tell you everything you want to know.
John
In the navigation box on the left click on Muncie 4 Speeds. This site will tell you everything you want to know.
John
:cheers:
Olivier
Team Owner
Joined: Jun 2001
Posts: 23,380
Likes: 1,067
From: Virginia USA
Re: 4-speed question: M20 or M21???? (GrandSportC3)
Don't really know. Did you take the shifter linkage arms off the shafts (if this is the way yours is set up)? The cover you mean is on the left side of the tranny, correct? Someone here will help you. Hope you liked that site, it's pretty cool. That is where I am going to buy my rebuild kit, but again, something else (front end is worn completely out, working on that now) so the rebuild has been pushed back one project.:lol: :lol:
John
John
Thread Starter
Team Owner
Joined: Jul 2001
Posts: 182,997
Likes: 88
From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Re: 4-speed question: M20 or M21???? (theandies)
Don't really know. Did you take the shifter linkage arms off the shafts (if this is the way yours is set up)? The cover you mean is on the left side of the tranny, correct? Someone here will help you. Hope you liked that site, it's pretty cool. That is where I am going to buy my rebuild kit, but again, something else (front end is worn completely out, working on that now) so the rebuild has been pushed back one project.:lol: :lol:
John
John
:cheers:
Olivier
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Thread Starter
Team Owner
Joined: Jul 2001
Posts: 182,997
Likes: 88
From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Re: 4-speed question: M20 or M21???? (GrandSportC3)
I finally got the inspection cover off.. It's not a M-22 but I still have to figure out if it's a M-20 or M-21...
:cheers:
Olivier
[Modified by GrandSportC3, 9:12 AM 7/8/2002]
:cheers:
Olivier
[Modified by GrandSportC3, 9:12 AM 7/8/2002]
Thread Starter
Team Owner
Joined: Jul 2001
Posts: 182,997
Likes: 88
From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Re: 4-speed question: M20 or M21???? (theandies)
Go here http://www.5speeds.com/index.html
In the navigation box on the left click on Muncie 4 Speeds. This site will tell you everything you want to know.
John
In the navigation box on the left click on Muncie 4 Speeds. This site will tell you everything you want to know.
John
:cheers:
Olivier
Thread Starter
Team Owner
Joined: Jul 2001
Posts: 182,997
Likes: 88
From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Re: 4-speed question: M20 or M21???? (Bob Jenkins)
I had taken my side cover off once and had a heck of a time getting the forks to go back in place properly.......careful :smash:
:cheers:
Olivier
