← All owner tools · Decode your own SPID label with the GM RPO decoder
| Code | Meaning | Years | Sourcing |
|---|---|---|---|
| 001 | P RAT, M RATIO, 3.70 | 1991 | GM sourced |
| 001 | Rat, M Ratio, 3.70 | 1991 | GM dated |
| 002 | P RAT, M RATIO, 4.11 (4 1/9) | 1991 | GM sourced |
| 002 | Rat, M Ratio, 4.11 (4 1/9) | 1991 | GM dated |
| 003 | Rat, M Ratio, 4.33 | 1991 | GM dated |
| 003 | P RAT, M RATIO, 4.33 | 1991 | GM sourced |
| 004 | Rat, M Ratio, 4.78 | 1994 | GM dated |
| 004 | P RAT, M RATIO, 4.78 | 1994 | GM sourced |
| 005 | Rat, M Ratio, 4.56 (4 5/9) | 1991 | GM dated |
| 005 | P RAT, M RATIO, 4.56 (4 5/9) | 1991 | GM sourced |
| 006 | Rat, M Ratio, 4.63 (4 5/8) | 1996 | GM dated |
| 006 | P RAT, M RATIO, 4.63 (4 5/8) | 1996 | GM sourced |
| 007 | Rat, M Ratio, 3.07 | 1997 | GM dated |
| 007 | P RAT, M RATIO, 3.07 | 1997 | GM sourced |
| 008 | Rat, M Ratio, 4.88 | 1996 | GM dated |
| 008 | P RAT, M RATIO, 4.88 | 1996 | GM sourced |
| 009 | Rat, M Ratio, 5.29 | 1991 | GM dated |
| 009 | P RAT, M RATIO, 5.29 | 1991 | GM sourced |
| 00A | Spare wheel upgrade Chevrolet Silverado 1500 | 2022–2023 | GM sourced |
| 00A | Wheel Spare 17 X 8.0, J, Steel, Design 2 | — | Reference |
| 00D | Not Equipped with Climate Control Knob Digital Temperature Display Chevrolet Silverado 1500 | 2022 | Provisional |
| 00G | Not Equipped with Heated Steering Wheel, see dealer for details Chevrolet Silverado 1500 | 2022–2023 | Provisional |
| 00L | Ccl, R Secondary Color, Exterior, Prime | 1989 | GM dated |
| 00L | P CCL, R SECONDARY COLOR, EXTERIOR, PRIME | 1989 | GM sourced |
| 00L | Exterior Color,secondary,prime,union City Body | — | GM dated |
| 00R | Not Equipped with Heated Rear Outboard Seats, see dealer for details Chevrolet Silverado 1500 | 2022–2023 | Provisional |
| 00U | Ccu, M Primary Color, Exterior, Prime | 1989 | GM dated |
| 00U | P CCU, M PRIMARY COLOR, EXTERIOR, PRIME | 1989 | GM sourced |
| 00U | Exterior Color,primary,prime,upper,union City Body | — | GM dated |
| 00V | Not Equipped with Heated or Ventilated Front Seats, see dealer for details Chevrolet Silverado 1500 | 2022–2023 | Provisional |
| 00Y | Not Equipped with Rear Park Assist, see dealer for details Chevrolet Silverado 1500 | 2022–2023 | Provisional |
| 00Z | Not Equipped with Front and Rear Park Assist, see dealer for details Chevrolet Silverado 1500 | 2022–2023 | Provisional |
| 010 | Rat, M Ratio, 5.43 | 1991 | GM dated |
| 010 | P RAT, M RATIO, 5.43 | 1991 | GM sourced |
| 011 | Rat, M Ratio, 5.57 (5 4/7) | 1991 | GM dated |
| 011 | P RAT, M RATIO, 5.57 (5 4/7) | 1991 | GM sourced |
| 012 | Rat, M Ratio, 5.83 | 1991 | GM dated |
| 012 | P RAT, M RATIO, 5.83 | 1991 | GM sourced |
| 013 | Rat, M Ratio, 3.73 | 1995 | GM dated |
| 013 | P RAT, M RATIO, 3.73 | 1995 | GM sourced |
| 014 | Rat, M Ratio, 6.14 (6 1/7) | 1991 | GM dated |
| 014 | P RAT, M RATIO, 6.14 (6 1/7) | 1991 | GM sourced |
| 015 | Rat, M Ratio, 6.17 | 1991 | GM dated |
| 015 | P RAT, M RATIO, 6.17 | 1991 | GM sourced |
| 016 | Rat, M Ratio, 5.25 | 1991 | GM dated |
| 016 | P RAT, M RATIO, 5.25 | 1991 | GM sourced |
| 017 | Rat, M Ratio, 6.50 | 1991 | GM dated |
| 017 | P RAT, M RATIO, 6.50 | 1991 | GM sourced |
| 018 | Rat, M Ratio, 6.65 | 1989 | GM dated |
| 018 | P RAT, M RATIO, 6.65 | 1989 | GM sourced |
| 019 | Rat, M Ratio, 6.67 | 1989 | GM dated |
| 019 | P RAT, M RATIO, 6.67 | 1989 | GM sourced |
| 01A | Stc, R Stripe Color, Accent, Two Tone, Silver/gunmetal (1995) | 1998 | GM dated |
| 01A | P STC, R STRIPE COLOR, ACCENT, TWO TONE, SILVER/GUNMETAL (1995) | 1998 | GM sourced |
| 01A | Stripe Color Accent, Two Tone, Silver/gunmetal | — | GM dated |
| 01A | Trim Color Seat Jet Black | — | GM dated |
| 01B | Trim Color Seat LT Neutral | — | Reference |
| 01C | Trim Color Seat LT Titanium | — | Reference |
| 01D | Trim Color Seat LT Cashmere | — | Reference |
| 01E | Trim Color Seat DK Titanium | — | Reference |
The full list, A to Z
Showing 401–500 of 633 codes beginning with M. One meaning shown per code — the best-sourced one we hold. Search above for the rest.
| Code | Meaning | Years | Sourcing |
|---|---|---|---|
| MM9 | P, MTC, M MERCHANDISED TRANS, CVT EQUIPMENT | 1999 | GM sourced |
| MME | Transmission Auto, Electric, Gm, Gxe, Gen 1, Drive Unit, X46f | — | Reference |
| MN0 | P, TRN, M TRANSMISSION, MAN 5 SPD, OPEL, 77 MM, 3.38 1ST, .71 5TH (F35 SR), 10328 E, 0 | — | Provisional |
| MN2 | P, MTC, M MERCHANDISED TRANS, MANUAL/AUTO EQUIPMENT, 10824 E, 0 | — | GM sourced |
| MN3 | P, TRN, M TRANSMISSION, AUTO 4 SPD, HMD, 4T65-E this code has more than one documented meaning — filter by year | 1997 | GM sourced |
| MN4 | P, TRN, M, TRANSMISSION, AUTO 4 SPD, HMD, 4T40-E | 1997 | GM sourced |
| MN5 | P, TRN, M, TRANSMISSION, AUTO 4 SPD, HMD, 4T45-E this code has more than one documented meaning — filter by year | 1997 | GM sourced |
| MN6 | P, MTC, M, MERCHANDISED TRANS, MAN 6 SPD PROVISIONS | 1990 | GM sourced |
| MN7 | P, TRN, M, TRANSMISSION, AUTO 4 SPD, HMD, 4T65-E, HEAVY DUTY this code has more than one documented meaning — filter by year | 1997 | GM sourced |
| MN8 | P, TRN, M, TRANSMISSION, AUTO 4 SPD, HMD, 4L80-E, HEAVY DUTY this code has more than one documented meaning — filter by year | 1998 | GM sourced |
| MNA | Equipment Military, Package #1 | — | Reference |
| MNB | Equipment Military, Package #2 | — | Reference |
| MNC | P, TRN, M, TRANSMISSION, MAN 5 SPD, EATON, 6.82 1ST, 1.28 4TH, DIRECT DRIVE this code has more than one documented meaning — filter by year | 1998 | GM sourced |
| MND | Equipment Military, Package #3 | — | Reference |
| MNF | P, TRN, M, TRANSMISSION, AUTO 4 SPD, AISIN-WARNER, A4-AF17, ELECTRONIC, 10515 E, 0 | — | GM sourced |
| MNG | Transmission Auto 4 Spd, Aisin-warner, AW 80-40le, Fwd, Gen2 | — | Reference |
| MNH | Transmission Auto 6 Spd, 6t40, Gen3, Var1 | — | Reference |
| MNI | P, LATCH, MINI WEDGE DOOR SYSTEM this code has more than one documented meaning — filter by year | 1996 | GM sourced |
| MNK | P, TRN, M, TRANSMISSION, AUTO 5 SPD, ALLISON, MD3060P, W/PTO DRIVE GEAR this code has more than one documented meaning — filter by year | 1998 | GM sourced |
| MNN | Equipment Maintenance Body | — | Reference |
| MNP | Transmission Auto 6 Spd, 6t45, Gen3 | — | Reference |
| MNR | Transmission Auto 6 Spd, 6t45, Gen2 | — | Reference |
| MNT | FAMILY CODE, MOUNT, 20531 | — | Provisional |
| MNZ | P, TRN, M, TRANSMISSION, AUTO 5 SPD, ALLISON, MD3560P, W/PTO DRIVE GEAR this code has more than one documented meaning — filter by year | 1998 | GM sourced |
| MO1 | H.D. CLUTCH | — | Provisional |
| MOD | P, MODULE, VEHICLE CONTROL | 1992 | GM sourced |
| MOE | P, MODULE, BODY CONTROL | 1997 | Provisional |
| MOJ | P, TRN, M, TRANSMISSION, MAN 5 SPD, EATON, FSO-2305, 3.48 1ST, 0.75 5TH, O/D | 1998 | Provisional |
| MOK | P, TRN, M, TRANSMISSION, MAN 5 SPD, EATON, FSO-2305G, 4.00 1ST, 0.75 5TH, O/D | 1998 | Provisional |
| MOL | P, TRN, M, TRANSMISSION, MAN 5 SPD, EATON, FSO-2305B, 4.08 1ST,.815 5TH, O/D | 1998 | Provisional |
| MON | P, VEHICLE, MONROE EQUIPMENT CO. | 1998 | GM sourced |
| MOR | P, TRN, M, TRANSMISSION, MAN 5 SPD, EATON, FS4205A, 8.05 1ST, 1.48 4TH, DIRECT DRIVE | 1998 | GM sourced |
| MOS | P, TRN, M, TRANSMISSION, MAN 5 SPD, EATON, FS4205B, 6.99 1ST, 1.28 4TH, DIRECT DRIVE | 1998 | GM sourced |
| MOU | P, TRN, M, TRANSMISSION, MAN 5 SPD, EATON, FS5205A, 7.52 1ST, 1.52 4TH, DIRECT DRIVE | 1998 | GM sourced |
| MOV | P, TRN, M, TRANSMISSION, MAN 5 SPD, EATON, FS5205C, 6.82 1ST, 1.17 4TH, DIRECT DRIVE | 1998 | GM sourced |
| MOW | P, TRN, M, TRANSMISSION, MAN 6 SPD, EATON, FS5206, 9.01 1ST, DIRECT DRIVE | 1998 | GM sourced |
| MOX | P, TRN, M, TRANSMISSION, MAN 5 SPD, EATON, FS6205A, 7.22 1ST, 1.39 4TH, DIRECT DRIVE | 1998 | GM sourced |
| MOY | P, TRN, M, TRANSMISSION, MAN 5 SPD, EATON, FS6205B, 7.22 1ST, 1.27 4TH, DIRECT DRIVE | 1998 | GM sourced |
| MP1 | Transmission Auto/man 6 Sp, Opel, M20, 4.273 1st, 2.158 | — | Reference |
| MP2 | P, TRN, M, TRANSMISSION, MAN 5 SPD, SATURN, 70MM, 3.08 1ST, .64 5TH, O/D this code has more than one documented meaning — filter by year | 1998 | GM sourced |
| MP3 | P, TRN, M, TRANSMISSION, MAN 5 SPD, SATURN, 70MM, 3.25 1ST, .73 5TH, O/D this code has more than one documented meaning — filter by year | 1998 | GM sourced |
| MP6 | P, TRN, M, TRANSMISSION, AUTO 4 SPD, SATURN, CONV CLUTCH this code has more than one documented meaning — filter by year | 1992 | GM sourced |
| MP7 | P, TRN, M, TRANSMISSION, AUTO 4 SPD, SATURN, ELECTRONIC CONV CLUTCH this code has more than one documented meaning — filter by year | 1992 | GM sourced |
| MP8 | P, TRN, M, TRANSMISSION, AUTO 6 SPD, ALLISON, MD3060P, W/PTO DRIVE GEAR this code has more than one documented meaning — filter by year | 1997 | GM sourced |
| MP9 | P, TRN, M, TRANSMISSION, AUTO 6 SPD, ALLISON, MD3000MH, W/PTO DRIVE GEAR, 20408 | — | Provisional |
| MPB | Transmission,man 7 Spd,fuller,t8607b,d/drive | — | Reference |
| MPD | P, KIT, SHIFT MODIFY, 3RD GEAR HOLD this code has more than one documented meaning — filter by year | 1999 | GM sourced |
| MPE | Transmission,man 13 Spd,fuller Rt6613,d/drive | — | Reference |
| MPG | P, CLU, R, CLUTCH, 13-1 CERAMIC PULLTYPE, DIAPHRAM SPRING, SELF ADJ, 20129 | — | Provisional |
| MPH | P, TRN, M, TRANSMISSION, MAN 10 SPD, FULLER, RT6610, DIRECT DRIVE this code has more than one documented meaning — filter by year | 1998 | GM sourced |
| MPJ | P, CLU, R, CLUTCH, 13 IN, CERAMETALIX, EATON VALEO, PUSH TYPE this code has more than one documented meaning — filter by year | 1998 | GM sourced |
| MPK | P, CLU, R, CLUTCH, 14-2 CERAMIC, PULL TYPE GREASEABLE BEARING this code has more than one documented meaning — filter by year | 1999 | GM sourced |
| MPL | P, CLU, R, CLUTCH, 14-1 CERAMIC, PULL TYPE, ANGLE SPRING, AELF ADJ, 10820 | — | GM sourced |
| MPM | P, CLU, R, CLUTCH, 14-1 CERAMIC, PULL TYPE, DIAPHRAM SPRING, SELF ADJ, 10820 | — | GM sourced |
| MPN | Clutch Ceramic, Hydraulic | — | Reference |
| MPP | P, EQUIPMENT, TRANSMISSION PARK PAWL this code has more than one documented meaning — filter by year | 1996 | GM sourced |
| MPQ | Transmission Auto 6 Spd, Allison, 2550rds/hs Conv Clutch, With Park Pawl. | — | Reference |
| MPR | Transmission Auto 6 Spd, Allison, 2550evs, Conv Clutch With Park Pawl | — | Reference |
| MPS | Transmission Auto 6 Spd, Allison, 2500rds/hs Conv Clutch NO Park Pawl. | — | Reference |
| MPU | P, TRN, M, TRANSMISSION, MAN 5 SPD, EATON, 7.52 1ST, 1.52 4TH, O/D this code has more than one documented meaning — filter by year | 1998 | GM sourced |
| MPV | Transmission,man 5 Spd Clark/fuller,fs5005c,d/drive this code has more than one documented meaning — filter by year | — | Reference |
| MPW | Transmission,manual 4-speed(borg-warner) | — | Reference |
| MQ7 | Transmission Man 5 Spd, Tremec, 109mm, 6.16 1st, 3.11 2nd, 1.71 3rd, 1.00 4th, 0.76 5th (tr4050) | — | Reference |
| MQB | Transmission, 10-speed automatic | 2026 | GM sourced |
| MQC | Transmission, 10-speed automatic | 2026 | GM sourced |
| MQE | Transmission, 8-speed automatic | 2022–2023 | Provisional |
| MR0 | P, TRN, M, TRANSMISSION, MAN 5 SPD, AISIN, 72 MM, 3.704 1ST, 0.802 5TH | 1999 | Provisional |
| MR1 | P, TRN, M, TRANSMISSION, AUTO 6 SPD, HMD, X10R (300LB.FT) | 1999 | GM sourced |
| MR2 | P, CLU, R, CLUTCH, 302 MM, SINGLE PLATE, PUSH TYPE, VALEO this code has more than one documented meaning — filter by year | 1994 | GM sourced |
| MR3 | P, TRN, M, TRANSMISSION, AUTO 6 SPD, EATON, F08406A-ASX, 20408 this code has more than one documented meaning — filter by year | — | GM sourced |
| MR4 | P, TRN, M, TRANSMISSION, MAN 6 SPD, ISUZU, 6.378 1ST, O/D, 523 E, 8 | — | Provisional |
| MR5 | Transmission Man 6 Spd, Opel, 76.5 Mm, 4.273 1st, 2.353 2nd, 1. 475 3rd, 1.067 4th, 0.875 5th, 0.744 | — | Reference |
| MR6 | Transmission Man 6 Spd, Opel, 83mm, 3.92 1st, 0.62 6th (f40 Wr) Ptu, Helix Angle | — | Reference |
| MR7 | P, TRN, M, TRANSMISSION, MAN 10 SPD, EATON RT7608, 11, 18.18 1ST | 1998 | Provisional |
| MR8 | Transmission,cvt Fwd | — | Reference |
| MR9 | P, TRN, M, TRANSMISSION, MAN 5 SPD, ISUZU, 69.5MM, 3.78 1ST, O/D | 1997 | Provisional |
| MRA | Transmission Auto Cvt | — | Reference |
| MRI | Family Code, Mirror I/s FRT Van | 1998 | GM dated |
| MRJ | P, CLU, R, CLUTCH, 310 MM, SINGLE PLATE, PUSH TYPE, DANA-SPICER this code has more than one documented meaning — filter by year | 1990 | GM sourced |
| MRK | P, CLU, R, CLUTCH, 350 MM, SINGLE PLATE, PUSH TYPE, DANA-SPICER this code has more than one documented meaning — filter by year | 1995 | GM sourced |
| MRV | Clutch Auto Shift,hydraulic | — | Reference |
| MRW | P, CLU, R, CLUTCH, 14 IN, SINGLE PLATE, PUSH TYPE, LIPE this code has more than one documented meaning — filter by year | 1998 | GM sourced |
| MRZ | P, CLU, R, CLUTCH, 330 MM, SINGLE PLATE, PUSH TYPE, LIPE this code has more than one documented meaning — filter by year | 1990 | GM sourced |
| MS0 | P, TRN, M, TRANSMISSION, MAN 5 SPD, GETRAG, F23, 5T45E, 75MM, 1ST 3,58, 2ND 2.02, 3RD 1.35, 4TH 0.98, 5TH 0.69 | 1999 | GM sourced |
| MS4 | P, TRN, M, TRANSMISSION, MAN 6 SPD, ISUZU, 135MM, 7.17 1ST, DIRECT DRIVE | 1998 | Provisional |
| MS5 | P, TRN, M, TRANSMISSION, MAN 5 SPD, AISIN, 74 MM, 3.704 1ST, 0.802 5TH, 10327 E, 5 | — | Provisional |
| MS6 | P, TRN, M, TRANSMISSION, MAN 5 SPD, AISIN, 74 MM, 3.566 1ST, 0.810 5TH, 10328 E, 5 | — | Provisional |
| MS7 | P, TRN, M, TRANSMISSION, AUTO 4 SPD, TOYOTA, ELECTRONIC CONV CLUTCH | 1987 | GM sourced |
| MS9 | P, TRN, M, TRANSMISSION, MAN 9 SPD, EATON, RT8709, DIRECT DRIVE this code has more than one documented meaning — filter by year | 1998 | GM sourced |
| MSA | Transmission Man 5 Spd, D20 M/cr, 1st 3.818 , 5th 0.868 this code has more than one documented meaning — filter by year | — | Reference |
| MSC | P, TRN, M, TRANSMISSION, MAN 5 SPD, EATON, 6.99 1ST, 1.28 4TH, DIRECT DRIVE this code has more than one documented meaning — filter by year | 1998 | GM sourced |
| MSG | P, TRN, M, TRANSMISSION, MAN 5 SPD, EATON, 8.05 1ST, DIRECT DRIVE this code has more than one documented meaning — filter by year | 1998 | GM sourced |
| MSK | P, PLT, R, PLANT CODE, MISHAWAKA, IN, USA, 407 | — | GM sourced |
| MSL | P, PLT, R, PLANT CODE, SILAO, MEXICO this code has more than one documented meaning — filter by year | 1997 | GM sourced |
| MSM | Family Code, Model Conversion | 1988 | GM dated |
| MT1 | 4L80-E four-speed heavy-duty automatic transmission | 2007 | GM sourced |
| MT2 | P, TRN, M, TRANSMISSION, MAN 6 SPD, OPEL, 83MM, 3.77 1ST, 0.62 6TH (F40 WR), 10131 this code has more than one documented meaning — filter by year | — | GM sourced |
| MT3 | P, TRN, M, TRANSMISSION, MAN 10 SPD, EATON, RT8908LL, DIRECT DRIVE this code has more than one documented meaning — filter by year | 1998 | GM sourced |
| MT5 | P, TRN, M, TRANSMISSION, MAN 5 SPD, NISSAN, 67MM, 3.06 1ST, O/D | 1987 | Provisional |
| MT6 | P, TRN, M, TRANSMISSION, MAN 5 SPD, ISUZU, 69.5MM, 4.99 1ST, O/D | 1997 | Provisional |
Using the master list
This is the full GM RPO code list we hold — every Regular Production Option code in the database, searchable by code or by description and filterable to a single model year. Most RPO lists on the internet run to a couple of hundred codes copied from one service manual. This one holds 24,366, and tells you where each meaning came from.
What an RPO code is
RPO stands for Regular Production Option. Every piece of factory equipment on a GM vehicle carries a three-character code, and the ones fitted to your truck are printed on the Service Parts Identification label in the glove box or on the door jamb. G80 is a locking differential, Z71 is an off-road suspension package, K05 is a block heater.
They matter because they are what the factory actually built, not what a listing claims. If you are buying a truck, the label settles the argument. If you are ordering parts, the axle and transmission codes decide which part fits.
Why the same code means different things
GM has reused these codes for decades and across every division. A code that means one thing on a 1978 pickup can mean something unrelated on a 2015 SUV, and plenty of entries in circulation come from bulk listings with no year and no document behind them.
So every entry here is labelled with where it came from. GM sourced means we hold an actual GM document for it. GM dated means it comes from the option master with a date attached. Reference means it is in general circulation with nothing dated behind it — still useful, but treat it as a lead rather than a fact. Filtering by your model year is the single best way to get an answer you can rely on.
Read the codes off your own label
If you have the sticker in front of you, the RPO decoder will read a photo of it and decode every code at once, checked against your model year.
FullSizeChevy.com is not affiliated with, endorsed by, or sponsored by General Motors. Chevrolet, GMC, Cadillac, Silverado, Sierra and related marks are trademarks of General Motors LLC and are used here only to identify applicable vehicles. RPO meanings vary by model year, platform and configuration — verify against your own label before buying parts.