What gear ratios are on a Ford Srod transmission?
There isn’t a single fixed set of gear ratios for the Ford SROD. The SROD, or Single Range Overdrive, was Ford’s four-speed manual transmission used in various trucks and cars during the late 1970s through the mid-1980s. The exact ratios varied by year and model, with the fourth gear serving as an overdrive and the first three gears spaced differently depending on application.
To understand the question in more detail, it’s important to recognize that Ford produced multiple versions of the SROD over its production life. Differences in gearing arose from model-specific needs, regional market requirements, and revisions in manufacturing. For someone restoring or rebuilding an SROD, identifying the precise ratios requires checking the transmission case tag, the vehicle’s original documentation, or Ford’s official service manuals for the specific year and model.
Common configurations and how to read them
Before examining any ratios, note that the SROD’s gearing was not standardized across all units. The most reliable information comes from the transmission’s case tag or factory manuals. The ranges below reflect typical gearing you may encounter in service literature and owner discussions.
- First gear: commonly around 3.0:1 to 3.9:1, providing the initial torque for starting off in a variety of driving conditions.
- Second gear: typically about 1.6:1 to 2.0:1, offering a balanced step up from first for acceleration.
- Third gear: generally in the range of 1.0:1 to 1.4:1, serving as the mid-range for everyday driving.
- Fourth gear: the overdrive, usually near 0.70:1 to 0.85:1, designed to reduce engine RPM at highway speeds.
These ranges capture the general spacing of gears rather than a single fixed set. Exact numbers must be verified for a given vehicle to account for the specific SROD variant installed.
How to identify your exact ratios
Because the SROD existed in multiple variants, the most dependable way to determine the precise gear ratios for a particular transmission is to locate and read the case tag or code printed on the housing. If the tag is missing or unreadable, use the vehicle’s original documentation and VIN to pull the factory specifications for that year and model. In a rebuild, technicians may count gear teeth or consult the official workshop manual to confirm the exact gear set.
- Inspect the transmission case for stamped codes or a small identification tag near the tail housing or side cover.
- Match the code to Ford’s published SROD ratio tables for the specific year and model.
- When possible, confirm with the vehicle’s build sheet or original window sticker to ensure you’re using the correct gear set for that production run.
In practice, owners should rely on the case tag and official manuals for precise ratios, since the SROD’s gearing varied across production years and vehicle applications.
Summary
The Ford SROD’s gear ratios are not identical across all units. While the fourth gear acts as an overdrive, the first three gears follow different spacings depending on year and model. To determine the exact numbers for a given transmission, identify the case code and consult Ford’s service literature or the vehicle’s original documentation.
