GM RPO Codes – Factory Identification Labels and Interpretation
GM RPO Codes, or General Motors “Regular Production Option” codes contain lots of valuable information about your GM vehicle. This tag includes info about equipment that was originally installed during the manufacturing phase. Everything from paint color & engine options to….you guessed it, Axle and Differential specs.
The GM RPO Codes label is usually located inside the glove box or on the Driver’s Side Door Jamb (on the B-Pillar). The silver placard will be labeled “Service Parts Identification” and includes a bunch of three-digit codes.
The prefix for GM RPO codes relevant to Axle Identification is almost always “G”. We call them G codes…look for G80, GT3, etc. Occasionally an “F” or “H” prefix will be used when referring to Axle Identification.
Keep in mind that any information obtained using the GM RPO code assumes that the rear end has not been previously modified.
Need help with identification? Call or send us an email here: Contact Us | Sierra Gear & Axle – Sierra Gear & Axle Online
Found what you need? Find a dealer here: Find a Dealer | Sierra Gear & Axle – Sierra Gear & Axle Online
GM RPO Codes:
Ring and Pinion Repair and GM RPO Codes chart.
GM RPO Codes |
||||
| RPO Code | Description | Ratio | ||
| F16 | Transaxle Final Drive | 2.53 | ||
| F17 | Transaxle Final Drive | 2.84 | ||
| F18 | Transaxle Final Drive | 2.65 | ||
| F25 | Transaxle Final Drive | 3.32 | ||
| F29 | Transaxle Final Drive | 2.82 | ||
| F36 | Axle Front | 2.19 | ||
| F45 | Axle Front | 2.93 | ||
| F47 | Axle Front | 2.73 | ||
| F57 | Axle Front | 3.15 | ||
| F62 | Transaxle Final Drive | 2.39 | ||
| F67 | Transaxle Final Drive | 3.19 | ||
| F68 | Transaxle Final Drive | 3.45 | ||
| F75 | Transaxle Final Drive | 3.18 | ||
| F77 | Transaxle Final Drive | 3.73 | ||
| F79 | Transaxle Final Drive | 2.97 | ||
| F82 | Transaxle Final Drive | 3.23 | ||
| F83 | Transaxle Final Drive | 3.05 | ||
| F90 | Axle Front | 2.73 | ||
| FA0 | Rear | 5.77 | ||
| FA1 | Rear 2 Speed | 4.88/6.94 | ||
| FA2 | Rear 2 Speed | 4.88/6.94 | ||
| FH5 | Transaxle Final Drive | 2.81 | ||
| FH6 | Axle Front | 3.64 | ||
| FH7 | Transaxle Final Drive | 4.12 | ||
| FH8 | Axle Front | 2.40 | ||
| FH9 | Transaxle Final Drive | 2.60 | ||
| FJ1 | Axle Front | 4.18 | ||
| FJ2 | Axle Front | 3.74 | ||
| FJ3 | Transaxle Final Drive | 3.35 | ||
| FJ4 | Axle Front | 4.53 | ||
| FJ5 | Axle Front | 4.19 | ||
| FJ7 | Axle Front | 4.56 | ||
| FP0 | Transaxle Final Drive | 2.55 | ||
| FP1 | Transaxle Final Drive | 2.72 | ||
| FP2 | Transaxle Final Drive | 3.58 | ||
| FP3 | Transaxle Final Drive | 2.73 | ||
| FP4 | Transaxle Final Drive | 2.69 | ||
| FP5 | Transaxle Final Drive | 2.95 | ||
| FP6 | Transaxle Final Drive | 3.54 | ||
| FP7 | Transaxle Final Drive | 3.73 | ||
| FP8 | Transaxle Final Drive | 3.54 | ||
| FP9 | Transaxle Final Drive | 3.54 | ||
| FQ2 | Transaxle Final Drive | 3.48 | ||
| FQ3 | Transaxle Final Drive | 2.86 | ||
| FQ4 | Transaxle Final Drive | 3.57 | ||
| FQ6 | Transaxle Final Drive | 4.12 | ||
| FQ8 | Transaxle Final Drive | 2.96 | ||
| FQ9 | Transaxle Final Drive | 3.21 | ||
| FR2 | Transaxle Final Drive | 2.93 | ||
| FR3 | Transaxle Final Drive | 3.69 | ||
| FR6 | Transaxle Final Drive | 3.84 | ||
| FR7 | Transaxle Final Drive | 3.95 | ||
| FR8 | Axle Front | 4.17 | ||
| FR9 | Transaxle Final Drive | 3.29 | ||
| FV0 | Transaxle Final Drive | 3.67 | ||
| FV1 | Transaxle Final Drive | 3.72 | ||
| FV2 | Transaxle Final Drive | 4.18 | ||
| FV3 | Transaxle Final Drive | 3.11 | ||
| FV4 | Transaxle Final Drive | 3.71 | ||
| FV5 | Transaxle Final Drive | 4.19 | ||
| FV6 | Transaxle Final Drive | 4.24 | ||
| FV7 | Transaxle Final Drive | 4.29 | ||
| FV8 | Transaxle Final Drive | 4.31 | ||
| FV9 | Transaxle Final Drive | 4.53 | ||
| FVO | Transaxle Final Drive | 3.67 | ||
| FW2 | Transaxle Final Drive | 3.06 | ||
| FW3 | Transaxle Final Drive | 4.02 | ||
| FW4 | Transaxle Final Drive | 3.89 | ||
| FW5 | Transaxle Final Drive | 4.10 | ||
| FW6 | Transaxle Final Drive | 3.42 | ||
| FW7 | Transaxle Final Drive | 3.83 | ||
| FW8 | Transaxle Final Drive | 4.28 | ||
| FW9 | Transaxle Final Drive | 3.43 | ||
| FWS | Transaxle Final Drive | 4.10 | ||
| FX1 | Transaxle Final Drive | 3.94 | ||
| FX2 | Transaxle Final Drive | 2.66 | ||
| FX4 | Transaxle Final Drive | 3.35 | ||
| FX8 | Transaxle Final Drive | 3.61 | ||
| FY1 | Transaxle Final Drive | 2.36 | ||
| FY3 | Transaxle Final Drive | 3.79 | ||
| FY5 | Transaxle Final Drive | 3.52 | ||
| G11 | Transaxle Final Drive | 2.56 | ||
| G44 | Axle Rear | 3.07 | ||
| G72 | Axle Rear | 2.14 | ||
| G75 | Axle Rear | 3.62 | ||
| G76 | Positraction Rear | |||
| G80 | Not Open Diff – Positraction / Limited Slip / Typ. Gov-Lock | |||
| G81 | Positraction Rear Axle | |||
| G82 | Axle Rear | 4.56 | ||
| G84 | Axle Rear | 4.10 | ||
| G86 | Axle Rear, Limited Slip | |||
| G87 | Ring Gear, 8.5″ | |||
| G89 | Ring Gear, 7.5″ | |||
| G90 | Rear | 3.15 | ||
| G91 | Special Highway Rear Axle | 3.08 | ||
| G94 | Axle Rear | 3.31 | ||
| G96 | Axle Rear | 3.55 | ||
| G97 | Axle Rear | 2.73 | ||
| GH0 | Axle Rear | 3.54 | ||
| GH2 | Axle Rear | 2.29 | ||
| GH3 | Axle Rear | 2.77 | ||
| GH4 | Axle Rear | 2.92 | ||
| GH7 | Axle Rear | 2.73 | ||
| GJ1 | Axle Rear | 5.38 | ||
| GJ2 | Axle Rear | 5.13 | ||
| GK7 | Axle Rear | 4.78 | ||
| GK8 | Axle Rear | 4.33 | ||
| GK9 | Axle Rear | 4.63 | ||
| GL0 | Axle Rear | 5.13 | ||
| GL3 | Axle Rear | 6.17 | ||
| GM1 | Axle Rear | 2.59 | ||
| GM2 | Axle Rear | 3.44 | ||
| GM3 | Axle Rear | 3.45 | ||
| GM4 | Axle Rear | 3.67 | ||
| GM5 | Axle Rear | 3.89 | ||
| GM6 | Axle Rear | 4.22 | ||
| GM7 | Axle Rear | 3.68 | ||
| GM8 | Axle Rear | 2.56 | ||
| GN9 | Axle Rear | 4.11 | ||
| GS1 | Axle Rear | 2.73 | ||
| GS3 | Axle Rear | 3.73 | ||
| GS4 | Axle Rear | 3.70 | ||
| GS5 | Axle Rear | 4.11 | ||
| GS6 | Axle Rear | 4.56 | ||
| GS8 | Axle Rear | 3.94 | ||
| GT1 | Axle Rear | 2.56 | ||
| GT2 | Axle Rear | 2.29 | ||
| GT4 | Axle Rear (Dup of 5X1) | 3.73 | ||
| GT5 | Axle Rear (Dup of GT8) | 4.10 | ||
| GT7 | Axle Rear | 3.33 | ||
| GT8 | Axle Rear (Dup of GT5) | 4.10 | ||
| GU1 | Axle Rear | 2.41 | ||
| GU2 | Axle Rear | 2.73 | ||
| GU3 | Axle Rear | 2.93 | ||
| GU4 | Axle Rear | 3.08 | ||
| GU5 | Axle Rear | 3.23 | ||
| GU6 | Axle Rear | 3.42 | ||
| GU7 | Axle Rear | 2.77 | ||
| GU8 | Axle Rear | 3.90 | ||
| GU9 | Axle Rear | 3.91 | ||
| GV0 | Axle Rear | 3.55 | ||
| GV1 | Axle Rear | 2.73 | ||
| GV2 | Axle Rear | 5.83 | ||
| GV3 | Axle Rear | 3.08 | ||
| GV4 | Axle Rear | 3.36 | ||
| GV5 | Axle Rear | 3.55 | ||
| GV7 | Axle Rear | 4.11 | ||
| GV8 | Axle Rear | 2.72 | ||
| GV9 | Axle Rear | 4.25 | ||
| GW2 | Axle Rear | 2.56 | ||
| GW3 | Axle Rear | 2.56 | ||
| GW4 | Axle Rear | 3.31 | ||
| GW5 | Axle Rear | 2.73 | ||
| GW6 | Axle Rear | 3.27 | ||
| GW8 | Axle Rear | 4.10 | ||
| GW9 | Axle Rear (Dup of GU3) | 2.93 | ||
| GX1 | Axle Rear | 3.70 | ||
| GX2 | Axle Rear | 3.07 | ||
| GX3 | Transaxle Final Drive | 3.33 | ||
| GX4 | Axle Rear | 3.75 | ||
| GX5 | Axle Rear | 4.09 | ||
| GX6 | Axle Rear | 3.53 | ||
| GX8 | Transaxle Final Drive | 3.74 | ||
| GY2 | Axle Rear | 3.31 | ||
| GY3 | Transaxle Final Drive | 4.29 | ||
| GY4 | Axle Rear | 4.53 | ||
| GY5 | Axle Front | 3.65 | ||
| GY7 | Transaxle Final Drive | 4.18 | ||
| GY9 | Axle Rear | 4.31 | ||
| GYS | Transaxle Final Drive | 3.65 | ||
| H01 | Axle Rear | 3.07 | ||
| H04 | Axle Rear, Single Speed | 4.11 | ||
| H05 | Axle Rear | 3.73 | ||
| H12 | Axle Rear, 21000 Lbs, Eaton 21065S, Single Speed | |||
| H42 | Axle Rear | 6.17 | ||
| H43 | Axle Rear | 5.43 | ||
| HA3 | Axle Rear, Single Speed | 5.29 | ||
| HC4 | Axle Rear | 4.56 | ||
| HC7 | Axle Rear, 7500 Lbs, Single Speed | 2.38 | ||
| HC8 | Axle Rear, Single Speed, Truck | 3.21 | ||
| HC9 | Axle Rear | 5.13 | ||
| HE3 | Axle Rear, 3500 Lbs, Single Speed | 3.07 | ||
| HE4 | Axle Rear | 3.40 | ||
| HF7 | Axle Rear, 10000 Lbs, Dana 70, Single | 4.56 | ||
| HF8 | Axle Rear | 4.88 | ||
| HJ1 | Axle Rear | 4.55 | ||
| HJ2 | Axle Rear | 5.86 | ||
| HJ3 | Axle Rear | 4.75 | ||
| HJ4 | Axle Rear | 6.50 | ||
| HJ5 | Axle Rear | 5.57 | ||
| HJ6 | Axle Rear | 4.78 | ||
| HJ7 | Axle Rear | 4.88 | ||
| HK1 | Axle Rear | 2.87 | ||
| HK3 | Axle Rear | 6.14 | ||
| HK9 | Axle Rear 10000 Lbs, Single Spd | 5.86 | ||
| HO4 | Axle Rear | 4.11 | ||
| HO6 | Axle Rear | 4.63 | ||
Find a Dealer
Find the application and ratio you need? Locate a Sierra Gear & Axle Distributor near you.
Gear Calculator
Doing a gear ratio change but not sure what you want? Try our Differential Gear Calculator.