MN12 vs T56
Thread Starter
Racer
Joined: Jul 2003
Posts: 299
Likes: 0
From: Charlotte NC
MN12 vs T56
What would have to be changed swapped e.g. bell housing input output shafts or anything. I know some swaps have to be done to put one in the f bodies.
To install a MN12 transmission into a C5?
To install a MN12 transmission into a C5?
Melting Slicks
Joined: Feb 2007
Posts: 3,266
Likes: 8
From: Indian Rocks Beach FL
St. Jude Donor '08-'09-'10
There is no such thing as an MN12. The transmission I think you are referring to is the M12 which came standard in the '01-'04 Z06's. They bolt right in to any C5 that came with a manual transmission. All models other than the Z06 received the MM6 transmission. The M12 is different from the MM6 only in the gear ratios and the torque rating.
The M12 is rated at 400 ft/lbs while the MM6 is rated at 450 ft/lbs.
Both are T56 transmissions.
If you are looking to install a manual transmission in a C5 that originally came with an automatic, that's a whole different ballgame.
The M12 is rated at 400 ft/lbs while the MM6 is rated at 450 ft/lbs.
Both are T56 transmissions.
If you are looking to install a manual transmission in a C5 that originally came with an automatic, that's a whole different ballgame.
Melting Slicks
Joined: Feb 2007
Posts: 3,266
Likes: 8
From: Indian Rocks Beach FL
St. Jude Donor '08-'09-'10
Burning Brakes
Joined: Feb 2001
Posts: 793
Likes: 2
From: Milwaukee & Long Beach WI & CA
I think the info below from this thread this thread clarifies it:
I believe the separation, in more detail, is that ....
MM6=Borg Warner T56 Transmission
M12 = Borg Warner T56 Transmission (Z06 ratios)
MN6=code for manual transmission vehicle
ALL Manual C5 Corvettes come down the production line with code MN6, as that tells the factory to install clutch pedal, console for a manual shift, wiring harness, whatever ..... and coupe's and convertibles have code MM6 for their transmission, the Z06 has code M12 for its transmission.
The MX0 code for the automatics puts a different console and shift set-up in the car, a different brake pedal and no clutch or clutch hydraulics installed, etc. The MX0 and MN6 codes may apply to changes to the PCM software, radiator installation of a an auto trans cooler and line ... it is not just "cabin" items that can be tied to the installation codes.
MM6=Borg Warner T56 Transmission
M12 = Borg Warner T56 Transmission (Z06 ratios)
MN6=code for manual transmission vehicle
ALL Manual C5 Corvettes come down the production line with code MN6, as that tells the factory to install clutch pedal, console for a manual shift, wiring harness, whatever ..... and coupe's and convertibles have code MM6 for their transmission, the Z06 has code M12 for its transmission.
The MX0 code for the automatics puts a different console and shift set-up in the car, a different brake pedal and no clutch or clutch hydraulics installed, etc. The MX0 and MN6 codes may apply to changes to the PCM software, radiator installation of a an auto trans cooler and line ... it is not just "cabin" items that can be tied to the installation codes.
Le Mans Master
Joined: Jun 2002
Posts: 8,352
Likes: 103
From: In the pit, trying to love someone.
A Corvette trans can not be modified to fit an F body without a ridiculous amount of hassle and parts changing. If you want an M12 for your F-Body, get a 6 speed out of a 2004 to 2006 GTO. Otherwise you are wasting your time and money.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Pro
Joined: Feb 2003
Posts: 623
Likes: 11
From: Ankeny IA
Another option is to purchase a 3.90 or 4.10 rearend. You can purchase these for about the price of the M12 tranny and they are usually built to withstand more power. You'll still get lower gearing, but keep the ratio spacing of the MM6 which some prefer.
Thread Starter
Racer
Joined: Jul 2003
Posts: 299
Likes: 0
From: Charlotte NC
Its a z06 trans going into a C5. Thanks for the replies. Oh yeah 99c5ja1 the end result I still want 3.90 gears for my vette one day. I would love to move from 4.10s in my camaro to 4.30s or back to 4.56s. Mod budget is LOW right now. SUPER LOW. So I had to say SOME DAY.
