Gear box
Thread Starter
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Joined: Sep 2006
Posts: 67
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From: Wiltshire
Gear box
I have a manual 1977 C3 or I think you guys refer to it as a stick shift.
I took these numbers off the side of it can anybody tell me what they mean:
WL1162
17S416329
Does this mean I have an M20 or is there an M21
many thanks Jerry
I took these numbers off the side of it can anybody tell me what they mean:
WL1162
17S416329
Does this mean I have an M20 or is there an M21
many thanks Jerry
Racer
Joined: Aug 2006
Posts: 330
Likes: 3
From: Wellington, New Zealand
You have a super t10 box, its not a muncie. Here's a link you might find interesting.
http://www.corvettemagazine.com/2005...ssion-lead.asp
http://www.corvettemagazine.com/2005...ssion-lead.asp
Drifting
Joined: Sep 2006
Posts: 1,259
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From: MS
M20 or M21 has nothing to do with Muncie, it just means Wide Ratio or Close Ratio 4-speed manual.
Muncie was used through mid-74, then Warner thereafter.
If you have the L48 it will be the M20, the L82 could be either.
Muncie was used through mid-74, then Warner thereafter.
If you have the L48 it will be the M20, the L82 could be either.
Le Mans Master
Joined: Mar 2004
Posts: 7,493
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From: Little Rock AR
Originally Posted by mr303
Ahhhhhhhh sorry mate, your wrong!
For example M20 means wide ratio 4 speed but does not tell you the manufacturer. As for this tranny: "W" is Warner, then comes the date code and I believe the last digit would be "1" for wide ratio or as is the case here "2" for close ratio on a Warner box available with L-82 for '77.
Anybody have better reference material than me that can back up the Warner ratio codes?
-Mark.
Last edited by stingr69; Nov 9, 2006 at 08:40 PM.
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Drifting
Joined: Sep 2006
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From: MS
Originally Posted by mr303
Ahhhhhhhh sorry mate, your wrong!
M20 = wide ratio muncie
M21 = close ratio muncie
M22 = close ratio muncie with HD gear set (rock crusher)
M20 = wide ratio muncie
M21 = close ratio muncie
M22 = close ratio muncie with HD gear set (rock crusher)
Then explain to me why there were still M20s and M21s through 1979 when the old Muncies were discontinued in mid 1974?
Believe me, the M does NOT stand for Muncie as some people think.
ALL of GM's transmission options begin with M, ie: M38 Turbo 350, M40 Turbo 400 even M74 on the new Allison 6-speed.
M20 just means Wide Ratio. Heck in 1978, there were 2 different Wide Ratio 4-speeds and they were both M20s!!! The L48 had a Saginaw with 2.85 low and the L82 used the Warner with the 2.64 low.
2 different trannies with the same M20 RPO and neither made by Muncie.
Thread Starter
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Joined: Sep 2006
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From: Wiltshire
My car is a L48 so:
mr303
You have a super t10 box, its not a muncie.
So I have a super t10 box.
wfo76
M20 or M21 has nothing to do with Muncie, it just means Wide Ratio or Close Ratio 4-speed manual.
Muncie was used through mid-74, then Warner thereafter.
If you have the L48 it will be the M20,
so you think it is a super t10 box made by warner and is a M20 wide ratio box.
Stingr69
Actualy, he is right about the codes. For example M20 means wide ratio 4 speed but does not tell you the manufacturer.
As for this tranny: "W" is Warner, then comes the date code and I believe the last digit would be "1" for wide ratio or as is the case here "2" for close ratio on a Warner box available with L-82 for '77.
So is mine a close ratio box on a 1977 L48?
crash-ent
The last digit of the build date designates shift(1=1st shift, 2=2nd shift)
Hope this helps... Crash
Im not quite sure what you mean by 1st shift and 2nd shift !!
thanks for your help so far but as you can see I'm still a bit confused
but hey nothing new there then.
mr303
You have a super t10 box, its not a muncie.
So I have a super t10 box.
wfo76
M20 or M21 has nothing to do with Muncie, it just means Wide Ratio or Close Ratio 4-speed manual.
Muncie was used through mid-74, then Warner thereafter.
If you have the L48 it will be the M20,
so you think it is a super t10 box made by warner and is a M20 wide ratio box.
Stingr69
Actualy, he is right about the codes. For example M20 means wide ratio 4 speed but does not tell you the manufacturer.
As for this tranny: "W" is Warner, then comes the date code and I believe the last digit would be "1" for wide ratio or as is the case here "2" for close ratio on a Warner box available with L-82 for '77.
So is mine a close ratio box on a 1977 L48?
crash-ent
The last digit of the build date designates shift(1=1st shift, 2=2nd shift)
Hope this helps... Crash
Im not quite sure what you mean by 1st shift and 2nd shift !!
thanks for your help so far but as you can see I'm still a bit confused
but hey nothing new there then.
Drifting
Joined: Sep 2006
Posts: 1,259
Likes: 2
From: MS
Yes, 77 L48 manuals will only be the Wide Ratio Warner
Ratios: 2.64, 1.75, 1.33, 1.00
You might also see an "HS" stamped or painted on the left side,
this denotes the W/R 2.64 gear set.
The 1 or 2 "shift" numbers just mean the assembly plant worker's shift,
ie: assuming 1 would be the morning shift and 2 the afternoon
17S416329 is the VIN stamping and if your car's VIN ends in 7S416329
then this is the original tranny for the car.
Ratios: 2.64, 1.75, 1.33, 1.00
You might also see an "HS" stamped or painted on the left side,
this denotes the W/R 2.64 gear set.
The 1 or 2 "shift" numbers just mean the assembly plant worker's shift,
ie: assuming 1 would be the morning shift and 2 the afternoon
17S416329 is the VIN stamping and if your car's VIN ends in 7S416329
then this is the original tranny for the car.
Le Mans Master
Joined: Mar 2004
Posts: 7,493
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From: Little Rock AR
Originally Posted by UK Jerry
My car is a L48 so:
So is mine a close ratio box on a 1977 L48?
So is mine a close ratio box on a 1977 L48?
My source for the questonable "2" suffix meaning close ratio info was a book by Richard Prince which has been proved to be less than 100% accurate.
-Mark.
Racer
Joined: Aug 2006
Posts: 330
Likes: 3
From: Wellington, New Zealand
WFO76. In general talking, people refer to muncies as M20, M21 etc. Even though the option code was still M20 etc when the BW gearbox was used. I have not found that people refer to BW box's as a "M" gearbox.
Race Director
Joined: May 2005
Posts: 10,674
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From: Millington Illinois
St. Jude Donor '08-'09
Originally Posted by mr303
WFO76. In general talking, people refer to muncies as M20, M21 etc. Even though the option code was still M20 etc when the BW gearbox was used. I have not found that people refer to BW box's as a "M" gearbox.
Melting Slicks
Joined: Sep 2004
Posts: 3,225
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From: Northeast
Thread Starter
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Joined: Sep 2006
Posts: 67
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From: Wiltshire
Originally Posted by tracdogg2
Jerry, you should have Borg-warner ST10, not a muncie. Count the bolts holding the side cover on. Muncie has 7. ST10 has 9.
Mike
Mike
, many thanks for all your help,Cheers for now Jerry