10 or 26 splines?
Thread Starter
Pro
Joined: Mar 2018
Posts: 526
Likes: 113
From: Seattle WA
10 or 26 splines?
New member here. Car history and story coming soon. Before I do that I have a question please.
1975 L48 coupe with pro date of January 1975. Specced/ordered ordered from a WA State dealer in November of 1974. Delivered to the customer new in Spring of 1975 with an M20 wide ratio 4-speed.
I know I can just crawl under there and determine if I have a Muncie or Borg-Warner trans. I am curious to know if it can be stated for certain what trans came with the car from new given the information above and without a physical inspection of the vehicle.
Please see the accompanying, ummm, build sheet?
What do you all say? Does my transmission input shaft have 10 or 26 splines?
Thanks all~
kie
1975 L48 coupe with pro date of January 1975. Specced/ordered ordered from a WA State dealer in November of 1974. Delivered to the customer new in Spring of 1975 with an M20 wide ratio 4-speed.
I know I can just crawl under there and determine if I have a Muncie or Borg-Warner trans. I am curious to know if it can be stated for certain what trans came with the car from new given the information above and without a physical inspection of the vehicle.
Please see the accompanying, ummm, build sheet?
What do you all say? Does my transmission input shaft have 10 or 26 splines?
Thanks all~
kie
Thread Starter
Pro
Joined: Mar 2018
Posts: 526
Likes: 113
From: Seattle WA
Le Mans Master
Joined: Nov 2003
Posts: 5,771
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From: Maryland
St. Jude Donor '05, '09, '15
Tom
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Pro
Joined: Mar 2018
Posts: 526
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From: Seattle WA
I've read it more than once. In this thread for example...
https://www.corvetteforum.com/forums...-with-m21.html
Thread Starter
Pro
Joined: Mar 2018
Posts: 526
Likes: 113
From: Seattle WA
I'm pretty sure I have the answer. 26 splines is what my car has.
I asked my local Chevy dealer parts pro to look up the input shaft and clutch disc part number. I only told him I had a 1975 Corvette with a 4-speed manual. He gave me 360814 and 3989030 both of which correspond to parts with 26 splines. He didn't ask me for a production date nor did he ask if I had a Muncie or a B/W. This ebay link to a nos 74 to 79 Corvette M20 input shaft pretty much shuts the door...
https://www.ebay.com/itm/1974-1979-C...-/370819641444
So I've got a 1975 M20 option code Corvette that came with a Borg-Warner Super T10 from new.
I asked my local Chevy dealer parts pro to look up the input shaft and clutch disc part number. I only told him I had a 1975 Corvette with a 4-speed manual. He gave me 360814 and 3989030 both of which correspond to parts with 26 splines. He didn't ask me for a production date nor did he ask if I had a Muncie or a B/W. This ebay link to a nos 74 to 79 Corvette M20 input shaft pretty much shuts the door...
https://www.ebay.com/itm/1974-1979-C...-/370819641444
So I've got a 1975 M20 option code Corvette that came with a Borg-Warner Super T10 from new.
Le Mans Master
Joined: Nov 2003
Posts: 5,771
Likes: 694
From: Maryland
St. Jude Donor '05, '09, '15
I always thought M20 and M21 were Muncie only codes. Looks like I was wrong. I also found the "M" is the RPO code designation for transmissions. Not "Muncie". RPO M22 is HD Muncie only and I did find an RPO M08 that says Borg Warner but I don't know where that falls in all this. Oh well you found your answer on your own. Good!
Tom
Tom
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Thread Starter
Pro
Joined: Mar 2018
Posts: 526
Likes: 113
From: Seattle WA
I always thought M20 and M21 were Muncie only codes. Looks like I was wrong. I also found the "M" is the RPO code designation for transmissions. Not "Muncie". RPO M22 is HD Muncie only and I did find an RPO M08 that says Borg Warner but I don't know where that falls in all this. Oh well you found your answer on your own. Good!
Tom
Tom