What is the gear ratio of a 4L60e?
The 4L60E’s internal gear ratios for the four forward gears are approximately 2.97:1 in 1st, 1.63:1 in 2nd, 1.00:1 in 3rd, and 0.75:1 in 4th (overdrive). The overall gearing you experience on the road also depends on the vehicle’s rear axle ratio.
Internal gear ratios
The numbers below represent the standard internal gear set of most 4L60E transmissions used in GM vehicles (with minor year-to-year revisions possible). These values are what define engine-to-output speed in each gear.
- 1st gear: 2.97:1
- 2nd gear: 1.63:1
- 3rd gear: 1.00:1
- 4th gear (overdrive): 0.75:1
Note: There can be small variations by model year or revision. For precision on a specific unit, consult the vehicle’s build sheet, service manual, or transmission tag.
Final-drive and overall gearing considerations
To translate the transmission’s internal ratios into actual vehicle performance, multiply the chosen gear ratio by the rear axle (final-drive) ratio. This yields the overall gearing, which determines acceleration characteristics, cruising RPM, and towing capability. For example, with a common axle ratio of 3.73:1:
- Top gear in 4th: 0.75 × 3.73 ≈ 2.80:1
- 1st gear: 2.97 × 3.73 ≈ 11.08:1
Other axles (2.56, 2.73, 3.42, 3.73, 4.10, etc.) yield different overall gearings. Always combine the transmission ratios with the actual axle ratio on the vehicle to understand real-world performance.
Practical implications
Knowing these ratios helps with fuel economy planning, towing setup, and diagnosing shifts. For precise values on a specific vehicle, refer to the production tags, factory documentation, or GM service manuals that list the exact gear sets and axle specifications.
Summary
The 4L60E features four forward gears with internal ratios of about 2.97:1 (1st), 1.63:1 (2nd), 1.00:1 (3rd), and 0.75:1 (4th/overdrive). The effective gearing you experience depends on the rear axle ratio, which you determine by multiplying the transmission ratio by the final-drive ratio. This combination shapes acceleration, highway cruising, and towing performance.
What is the gear ratio of the 4L60E vs 4L80E?
While the 4L80E uses a 2.48 First and 1.48 Second gear just like the TH400, the 4L60E has a 3.06 First and 1.63 Second, which was a holdover from the 700-R4 and better suited to a dump truck or the anemic 305s of the era.
Is a 700R4 stronger than a 4L60E?
Which transmission is better for a performance build? It depends on your setup. The 700R4 can be more less-effective but simpler to work with in non-computer-controlled vehicles. The 4L60E offers better shift precision and tuning capabilities via a controller, making it ideal for modern, computer-integrated builds.
What is the gear ratio of the 4L60E?
The 4L60 (and 4L60E) has the following gear ratios: 1st gear is 3.06∶13.06 colon 13.06∶1, 2nd gear is 1.62∶11.62 colon 11.62∶1, 3rd gear is 1.00∶11.00 colon 11.00∶1, and 4th gear (overdrive) is 0.70∶10.70 colon 10.70∶1. A reverse gear ratio of approximately 2.29∶12.29 colon 12.29∶1 is also part of the transmission's design.
You can watch this video to learn about the power flow through the 4L60E transmission: 57sSouthpaw AutoworksYouTube · May 26, 2021
- 1st Gear: 3.06∶13.06 colon 13.06∶1
- 2nd Gear: 1.62∶11.62 colon 11.62∶1
- 3rd Gear: 1.00∶11.00 colon 11.00∶1
- 4th Gear (Overdrive): 0.70∶10.70 colon 10.70∶1
- Reverse: 2.29∶12.29 colon 12.29∶1
Is a 4L60E a 4 speed with overdrive?
General Motors manufactures the remarkable 4L60E in Romulus, Michigan, and Toledo, Ohio. In 1982, General Motors initially conceptualized the 4L60 and 4L60E as the 4-speed overdrive automatic transmission known as TH700R4.
