GM RPO Axle Codes
To find the axle gear ratio of any GM vehicle, locate the RPO sticker (typically located in the glove box) and write down any codes starting with F, G, or H. Then, find those codes in the table below.
GM RPO Axle Code Notes
These RPO codes are used to idicate a specific type of differential and/or ring gear size. Not all applications will have one of these codes but when they apply, they will be listed in addition to an axle code found in the main RPO axle code list below.
| RPO | Axle Type |
| G76 | Rear Axle (Posi) |
| G80 | Positraction |
| G81 | Positraction (Rear) |
| G86 | Limited Slip (Rear) |
| G87 | 8.5" Ring Gear |
| G89 | 7.5" Ring Gear |
RPO code data is ©Copyright Crawlpedia.com - Please provide a link back to this page when copying.
Data is accurate to the best of our knowledge through 2015 and is offered as-is with no guarantee.
GM RPO Axle Code List (F)
The following is a complete list of GM RPO axle codes for Chevy and GMC vehicles starting with the letter F.
| RPO | Axle Type | Ratio |
| F16 | Transaxle | 2.53 |
| F17 | Transaxle | 2.84 |
| F18 | Transaxle | 2.65 |
| F25 | Transaxle | 3.32 |
| F29 | Transaxle | 2.82 |
| F36 | Front Axle | 2.19 |
| F45 | Front Axle | 2.93 |
| F47 | Front Axle | 2.73 |
| F57 | Front Axle | 3.15 |
| F62 | Transaxle | 2.39 |
| F67 | Transaxle | 3.19 |
| F68 | Transaxle | 3.45 |
| F75 | Transaxle | 3.18 |
| F77 | Transaxle | 3.73 |
| F79 | Transaxle | 2.97 |
| F82 | Transaxle | 3.23 |
| F83 | Transaxle | 3.05 |
| F90 | Front Axle | 2.73 |
| FA0 | Rear Axle | 5.77 |
| FA1 | Rear Axle (2 Speed) | 4.88/6.94 |
| FA2 | Rear Axle (2 Speed) | 4.88/6.94 |
| FH5 | Transaxle | 2.81 |
| FH6 | Front Axle | 3.64 |
| FH7 | Transaxle | 4.12 |
| FH8 | Front Axle | 2.40 |
| FH9 | Transaxle | 2.60 |
| FJ1 | Front Axle | 4.18 |
| FJ2 | Front Axle | 3.74 |
| FJ3 | Transaxle | 3.35 |
| FJ4 | Front Axle | 4.53 |
| FJ5 | Front Axle | 4.19 |
| FJ7 | Front Axle | 4.56 |
| FP0 | Transaxle | 2.55 |
| FP1 | Transaxle | 2.72 |
| FP2 | Transaxle | 3.58 |
| FP3 | Transaxle | 2.73 |
| FP4 | Transaxle | 2.69 |
| FP5 | Transaxle | 2.95 |
| FP6 | Transaxle | 3.54 |
| FP7 | Transaxle | 3.73 |
| FP8 | Transaxle | 3.54 |
| FP9 | Transaxle | 3.54 |
| FQ2 | Transaxle | 3.48 |
| FQ3 | Transaxle | 2.86 |
| FQ4 | Transaxle | 3.57 |
| FQ6 | Transaxle | 4.12 |
| FQ8 | Transaxle | 2.96 |
| FQ9 | Transaxle | 3.21 |
| FR2 | Transaxle | 2.93 |
| FR3 | Transaxle | 3.69 |
| FR6 | Transaxle | 3.84 |
| FR7 | Transaxle | 3.95 |
| FR8 | Front Axle | 4.17 |
| FR9 | Transaxle | 3.29 |
| FV0 | Transaxle | 3.67 |
| FV1 | Transaxle | 3.72 |
| FV2 | Transaxle | 4.18 |
| FV3 | Transaxle | 3.11 |
| FV4 | Transaxle | 3.71 |
| FV5 | Transaxle | 4.19 |
| FV6 | Transaxle | 4.24 |
| FV7 | Transaxle | 4.29 |
| FV8 | Transaxle | 4.31 |
| FV9 | Transaxle | 4.53 |
| FVO | Transaxle | 3.67 |
| FW2 | Transaxle | 3.06 |
| FW3 | Transaxle | 4.02 |
| FW4 | Transaxle | 3.89 |
| FW5 | Transaxle | 4.10 |
| FW6 | Transaxle | 3.42 |
| FW7 | Transaxle | 3.83 |
| FW8 | Transaxle | 4.28 |
| FW9 | Transaxle | 3.43 |
| FWS | Transaxle | 4.10 |
| FX1 | Transaxle | 3.94 |
| FX2 | Transaxle | 2.66 |
| FX4 | Transaxle | 3.35 |
| FX8 | Transaxle | 3.61 |
| FY1 | Transaxle | 2.36 |
| FY3 | Transaxle | 3.79 |
| FY5 | Transaxle | 3.52 |
RPO code data is ©Copyright Crawlpedia.com - Please provide a link back to this page when copying.
Data is accurate to the best of our knowledge through 2015 and is offered as-is with no guarantee.
GM RPO Axle Code List (G)
The following is a complete list of GM RPO axle codes for Chevy and GMC vehicles starting with the letter G.
| RPO | Axle Type | Ratio |
| G11 | Transaxle | 2.56 |
| G44 | Rear Axle | 3.07 |
| G72 | Rear Axle | 2.14 |
| G75 | Rear Axle | 3.62 |
| G82 | Rear Axle | 4.56 |
| G84 | Rear Axle | 4.10 |
| G90 | Rear Axle | 3.15 |
| G91 | Rear Axle (HWY) | 3.08 |
| G94 | Rear Axle | 3.31 |
| G96 | Rear Axle | 3.55 |
| G97 | Rear Axle | 2.73 |
| GH0 | Rear Axle | 3.54 |
| GH2 | Rear Axle | 2.29 |
| GH3 | Rear Axle | 2.77 |
| GH4 | Rear Axle | 2.92 |
| GH7 | Rear Axle | 2.73 |
| GJ1 | Rear Axle | 5.38 |
| GJ2 | Rear Axle | 5.13 |
| GK7 | Rear Axle | 4.78 |
| GK8 | Rear Axle | 4.33 |
| GK9 | Rear Axle | 4.63 |
| GL0 | Rear Axle | 5.13 |
| GL3 | Rear Axle | 6.17 |
| GM1 | Rear Axle | 2.59 |
| GM2 | Rear Axle | 3.44 |
| GM3 | Rear Axle | 3.45 |
| GM4 | Rear Axle | 3.67 |
| GM5 | Rear Axle | 3.89 |
| GM6 | Rear Axle | 4.22 |
| GM7 | Rear Axle | 3.68 |
| GM8 | Rear Axle | 2.56 |
| GN9 | Rear Axle | 4.11 |
| GS1 | Rear Axle | 2.73 |
| GS3 | Rear Axle | 3.73 |
| GS4 | Rear Axle | 3.70 |
| GS5 | Rear Axle | 4.11 |
| GS6 | Rear Axle | 4.56 |
| GS8 | Rear Axle | 3.94 |
| GT1 | Rear Axle | 2.56 |
| GT2 | Rear Axle | 2.29 |
| GT4 | Rear Axle (5X1) | 3.73 |
| GT5 | Rear Axle (GT8) | 4.10 |
| GT7 | Rear Axle | 3.33 |
| GT8 | Rear Axle (GT5) | 4.10 |
| GU1 | Rear Axle | 2.41 |
| GU2 | Rear Axle | 2.73 |
| GU3 | Rear Axle | 2.93 |
| GU4 | Rear Axle | 3.08 |
| GU5 | Rear Axle | 3.23 |
| GU6 | Rear Axle | 3.42 |
| GU7 | Rear Axle | 2.77 |
| GU8 | Rear Axle | 3.90 |
| GU9 | Rear Axle | 3.91 |
| GV0 | Rear Axle | 3.55 |
| GV1 | Rear Axle | 2.73 |
| GV2 | Rear Axle | 5.83 |
| GV3 | Rear Axle | 3.08 |
| GV4 | Rear Axle | 3.36 |
| GV5 | Rear Axle | 3.55 |
| GV7 | Rear Axle | 4.11 |
| GV8 | Rear Axle | 2.72 |
| GV9 | Rear Axle | 4.25 |
| GW2 | Rear Axle | 2.56 |
| GW3 | Rear Axle | 2.56 |
| GW4 | Rear Axle | 3.31 |
| GW5 | Rear Axle | 2.73 |
| GW6 | Rear Axle | 3.27 |
| GW8 | Rear Axle | 4.10 |
| GW9 | Rear Axle (GU3) | 2.93 |
| GX1 | Rear Axle | 3.70 |
| GX2 | Rear Axle | 3.07 |
| GX3 | Transaxle | 3.33 |
| GX4 | Rear Axle | 3.75 |
| GX5 | Rear Axle | 4.09 |
| GX6 | Rear Axle | 3.53 |
| GX8 | Transaxle | 3.74 |
| GY2 | Rear Axle | 3.31 |
| GY3 | Transaxle | 4.29 |
| GY4 | Rear Axle | 4.53 |
| GY5 | Front Axle | 3.65 |
| GY7 | Transaxle | 4.18 |
| GY9 | Rear Axle | 4.31 |
| GYS | Transaxle | 3.65 |
GM RPO Axle Code List (H)
The following is a complete list of GM RPO axle codes for Chevy and GMC vehicles starting with the letter H.
| RPO | Axle Type | Ratio |
| H01 | Rear Axle | 3.07 |
| H04 | Rear Axle | 4.11 |
| H05 | Rear Axle | 3.73 |
| H12 | Rear Axle (Eaton 21065S) | -- |
| H42 | Rear Axle | 6.17 |
| H43 | Rear Axle | 5.43 |
| HA3 | Rear Axle | 5.29 |
| HC4 | Rear Axle | 4.56 |
| HC7 | Rear Axle (7,500 Lbs.) | 2.38 |
| HC8 | Rear Axle (Truck) | 3.21 |
| HC9 | Rear Axle | 5.13 |
| HE3 | Rear Axle (3,500 Lbs.) | 3.07 |
| HE4 | Rear Axle | 3.40 |
| HF7 | Rear Axle, (Dana 70) | 4.56 |
| HF8 | Rear Axle | 4.88 |
| HJ1 | Rear Axle | 4.55 |
| HJ2 | Rear Axle | 5.86 |
| HJ3 | Rear Axle | 4.75 |
| HJ4 | Rear Axle | 6.50 |
| HJ5 | Rear Axle | 5.57 |
| HJ6 | Rear Axle | 4.78 |
| HJ7 | Rear Axle | 4.88 |
| HK1 | Rear Axle | 2.87 |
| HK3 | Rear Axle | 6.14 |
| HK9 | Rear Axle (10,000 Lbs.) | 5.86 |
| HO4 | Rear Axle | 4.11 |
| HO6 | Rear Axle | 4.63 |
Other Ring and Pinion Gear Resources
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Gear Ratio Finder
Gear Ratio Calculator
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