Because different transmission gear ratios can greatly affect a drivetrain combination, it’s important for anyone performing a transmission swap to know the gear ratios of the gearboxes you might be installing in your vehicle.

We’ve assembled a variety of manual gear ratio charts for General Motors vehicles that we hope can help you avoid choosing the wrong transmission only to discover your hot rod or truck is performing like a 19th-century horse-drawn chuckwagon, minus the delicous beans and salt pork.

Planning a manual transmission swap in your Chevy or GM vehicle? Double-check your gear ratios. Here’s a good start.

interior of a customized 1965 corvette sting ray with a hurst line lock shifter and sun tach
This Sting Ray’s Muncie M21 is connected to a super-cool Hurst reverse lockout lever poking through the boot. (Image/George Lyons)

[NOTE: Not every transmission in GM’s history is listed here. It is mostly Camaro/Firebird/Corvette-focused. We’re sorry if you love a particular transmission not shown on this list. We promise it wasn’t intended as any sort of slight to the excluded GM-made transmissions.]

T-10 Four-Speed

TypeFirst GearSecond GearThird GearFourth Gear
A-code2.541.921.511.00
C-, F-code2.201.641.311.00
D-, E-, G-code2.541.891.511.00

Super T-10 Four-Speed

TypeFirst GearSecond GearThird GearFourth Gear
P-code
(wide ratio)
2.431.761.471.00
S-code
(close ratio)
2.431.611.231.00
U-code3.442.281.461.00
V-code2.231.771.351.00
W-code2.641.751.341.00
X-code2.641.611.231.00
Y-code2.881.741.331.00
Z-code3.422.281.461.00
AA-code3.291.721.001.00
BB-code4.172.281.461.00
CC-code2.881.911.331.00

Muncie M21/M22 Four-Speed

TypeFirst GearSecond GearThird GearFourth Gear
1963-772.201.641.271.00

Saginaw Three-Speed

TypeFirst GearSecond GearThird Gear
All2.541.881.00

Saginaw Four-Speed

TypeFirst GearSecond GearThird GearFourth Gear
All2.201.641.471.00

T-5 Five-Speed (Camaro/Firebird)

TypeFirst GearSecond GearThird GearFourth GearFifth Gear
1983-87 (V8)2.951.941.341.000.74
1988-92 (V8)2.951.941.341.000.73
1988-923.351.991.331.000.68
1988-923.972.341.461.000.79

T-56 Six-Speed (Camaro/Firebird)

TypeFirst GearSecond GearThird GearFourth GearFifth GearSixth Gear
1993 (wide ratio)3.362.071.351.000.840.62
1993 (close ratio)2.971.941.341.000.840.62
1994-20022.661.781.301.000.740.50

T-56 Six-Speed (Corvette)

TypeFirst GearSecond GearThird GearFourth GearFifth GearSixth Gear
1997-2007 Corvette (base)2.661.781.301.000.740.50
2001-07 Corvette Z062.972.071.431.000.840.56

ZF Six-Speed

TypeFirst GearSecond GearThird GearFourth GearFifth GearSixth Gear
1989-96 Corvette (LT1/4/5)2.681.801.311.000.750.50

T-6060 Six-Speed

TypeFirst GearSecond GearThird GearFourth GearFifth GearSixth Gear
2008-13 Corvette2.661.781.301.000.740.50
2008-09 Corvette Z512.972.071.431.000.710.57
2009 Pontiac G8 GXP2.972.101.461.000.710.56
2009-13 Cadillac
CTS-V
2.661.781.301.000.800.63
2010 Camaro SS3.012.071.431.000.840.57
2012-15 Camaro ZL12.661.781.301.000.800.63
2015-17 Chevrolet SS3.012.071.431.000.710.57
2016-17 Cadillac
ATS-V
2.661.781.301.000.790.63

M420 Four-Speed (Truck)

TypeFirst GearSecond GearThird GearFourth Gear
1957-677.203.571.701.00

M465 Four-Speed (Truck)

TypeFirst GearSecond GearThird GearFourth Gear
1968-906.543.571.571.00

NP435 Four-Speed (Truck)

TypeFirst GearSecond GearThird GearFourth Gear
All4.782.391.371.00

NV4500 Five-Speed (Truck)

TypeFirst GearSecond GearThird GearFourth GearFifth Gear
1995-20075.613.041.671.000.73