How big is the dual gas tank on a 73 87 Chevy truck?
There isn’t a single standard size. In factory dual-tank configurations for the 1973–1987 Chevy C/K trucks, the system typically includes a larger rear main tank and a smaller front auxiliary tank, with total capacities generally in the 35–50 gallon range.
The exact capacity varies by year, body style (short/long bed, regular or extended cab), drivetrain (2WD vs 4x4), and whether the truck was equipped with the dual-tank option or an aftermarket conversion. Some trucks used only one tank or had different combinations, and the dual-tank setup was more common on certain heavy-duty or long-bed configurations. To know the precise size for a specific truck, you’ll need to check factory documentation or physically inspect the tanks.
Overview of dual-tank configurations in these trucks
Factory dual-tank configurations varied with year, model, and body style. Below are the typical ranges you might encounter in period trucks.
- Front auxiliary tank capacity: about 10–20 gallons
- Rear main tank capacity: about 20–28 gallons
- Total system capacity: about 30–50 gallons
In practice, the exact numbers depend on the specific option package and chassis configuration. If your truck is equipped with two tanks, you can expect a combined capacity within this broad range, but the precise figure should be verified for the exact VIN and build.
How to verify the exact size on your truck
To confirm the exact capacity of your dual-tank system, use these steps to identify the correct specifications for your vehicle’s year and configuration.
- Check the vehicle’s option codes and build sheet (RPO stickers) or glove box tag to confirm whether the dual-tank setup was installed and in which configuration.
- Inspect the fuel tanks themselves for any stamped capacity, part numbers, or factory markings that indicate volume or model.
- Look up the original dealer or factory service manual, or consult GM parts catalogs for your VIN and body style to determine the standard tank sizes for that configuration.
- Verify with reliable sources such as a classic-truck forum, a GM archivist, or a dealership parts department that can cross-reference the VIN with documented options.
- If you still aren’t sure, have a qualified mechanic or classic-truck specialist measure or confirm the capacities using the correct service documentation for your exact year and model.
Keep in mind that two-tank installations can vary by year, cab/bed combination, and whether aftermarket modifications were made. Documentation and physical labeling are the most reliable ways to confirm exact capacities.
Summary
For 1973–1987 Chevy trucks, dual-fuel setups typically feature a larger rear main tank and a smaller front auxiliary tank, with a common total range around 30–50 gallons. Exact sizes depend on year, body style, drivetrain, and factory option packages. To determine the precise capacities for a specific truck, consult the build sheet or option codes, inspect the tanks for markings, reference the factory manuals or catalogs, and, if needed, seek guidance from knowledgeable specialists or enthusiasts.
How big is the gas tank on a 1986 Chevy C10?
16 Gallon
16 Gallon Fuel Tank For 82-86 Chevrolet C10 87 R10 Silver.
How big is the fuel tank on a squarebody?
Short is 16 gal; long is 20 gal.
Why do older trucks have two gas tanks?
In the 1970s through the 1990s, the interior and frame geometry of trucks sometimes left no room for a single, large fuel cell. Splitting capacity into front and rear, with a selector valve, allowed more total fuel without interfering with the drivetrain, suspension, or frame rails.
What were the specs of the 1973 Chevy pickup truck?
Powertrain. At its 1973 launch, the Rounded-Line pickup trucks were offered with five different engines. A 250-cubic-inch inline-six was standard, with the option of a 292-cubic-inch inline-6, a 307-cubic-inch V8, a 350-cubic-inch V8, and a 454-cubic-inch V8.
