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To upgrade a 1987 Chevy S10 to a 20-gallon fuel tank, you must first disconnect the fuel filler neck and remove the driveshaft to access the mounting area. The 20-gallon tank provides a 6.8-gallon increase over the 13.2-gallon standard size, which is the one originally installed. The 1987 Chevy S10 20-Gallon Fuel Tank Upgrade suits truck owners who want to increase range while skipping the upgrade is better for owners of modern electric trucks.
When to use this approach, and when not to
Readers who should use the 1987 Chevy S10 20-Gallon Fuel Tank Upgrade
- Owners of 1982-1993 Chevrolet S10 trucks should perform this upgrade to increase fuel capacity or clear out a bad gas smell in truck systems.
- DIY mechanics should use this method to learn how to safely remove a fuel tank without damaging the driveshaft.
- Project truck restorers should choose this upgrade because it is a period-correct factory option offered by GM in 1987.
- Drivers experiencing poor engine performance should follow these steps to diagnose the S10 injector spray pattern and replace clogged filters.
Readers who should skip the 1987 Chevy S10 20-Gallon Fuel Tank Upgrade
- Modern EV truck owners should skip this method and look for content regarding high-voltage fuel systems or EV batteries.
- People looking for new car buying advice should skip this project and instead look for new car reviews or leasing advice.
What to do next about the 1987 Chevy S10 20-Gallon Fuel Tank Upgrade
- Remove the 10-mm ground strap bolt to access the fuel lines.
- Mark the driveshaft U-joint and pipe with a marker to ensure proper alignment.
- Install the new O-ring and pump assembly into the 20-gallon tank.
- Cut fuel hoses to length using a razor blade and secure with hose clamps.
- Depressurize the fuel system by pulling the ECM fuse to safely remove the filter.
Driveshaft Removal and Marking
The driveshaft must be safely moved before the fuel tank can be dropped from the truck frame. Marking the U-joint and the pipe ensures the drivetrain remains aligned after the tank is reinstalled. Why would you risk a vibration? Accurate markings prevent the driveline from wobbling or causing noise during operation.
Removing and Cleaning the Original Fuel System
Removing the 13.2-gallon tank allows the owner to address issues like a bad gas smell in truck systems that may stem from old fuel. A jack is required to safely support the truck while the tank is lowered. The original pump assembly must be separated from the tank, and the old fuel should be drained into a container or a gas buggy.
Upgrading to a 20-Gallon Fuel Tank on the Chevrolet S10
The 20-gallon tank offers a 6.8-gallon increase over the 13.2-gallon standard size, which is the one originally installed. GM offered the larger capacity as a factory option in 1987, making this a period-correct upgrade. The new tank requires an alignment pin to sit perfectly in the cutout and specific straps to secure it to the frame.
Steps for fuel Tank Replacement Procedure
- Remove the 10-mm ground strap bolt.
- Disconnect the fuel filler neck and lines.
- Mark the driveshaft U-joint and pipe for alignment.
- Drop the fuel tank.
- Separate the fuel pump from the tank and drain old fuel.
- Install the new O-ring, pump, and sending unit into the 20-gallon tank.
- Cut fuel hoses to length and secure with new clamps.
- Reinstall the driveshaft using the alignment marks.
- Connect fuel lines and ground wires.
- Prime the system and test the injector spray pattern.
Reconnecting Lines and Final Assembly
Fuel lines must be cut to length and secured with new hose clamps to prevent leaks. A razor blade and vise grips can be used to trim the rubber hoses to the correct fit. Reinstalling the driveshaft using the alignment marks ensures the truck returns to its original configuration.
S10 Fuel Filter Location and Troubleshooting
The S10 fuel filter location is situated right next to the hot exhaust manifold, which can lead to heat-related clogs. Why did the original designers place the filter so close to the hot down pipe? This design choice may cause the filter to fail faster than in other vehicles. Checking the S10 injector spray pattern by removing the air cleaner and cranking the engine helps determine if the filter is blocked or if the pump is failing.
Think of the fuel pump as the heart of the system, pushing lifeblood to the injectors. If the filter is clogged, the heart cannot pump enough blood to reach the destination. The 1A Auto team recommends replacing the filter and pump assembly simultaneously to ensure consistent pressure.
The 20-gallon tank upgrade provides a way to move away from contaminated fuel and improve overall truck range. Removing the old 13.2-gallon tank is the first step toward a more capable fuel system. Success is confirmed when the engine fires up smoothly and the injector spray pattern is uniform.
1A Auto has not announced the specific price of the 20-gallon fuel tank
- 1A Auto has not announced the specific price of the 20-gallon fuel tank.
- The user should check the 1A Auto website for current pricing and availability.
A Case for Upgrading the S10 Fuel Capacity
Suppose Dave owns a 1988 Chevy S10 with 50,000 miles that has sat for a long time. Dave disconnects the 10-mm ground strap, marks his driveshaft, and drops the 13.2-gallon tank to replace it with the 20-gallon version. He installs the new pump, cuts his hoses to length, and replaces the clogged fuel filter. Dave successfully removes the smelly old fuel and gains a larger fuel capacity while maintaining the truck’s original character. If Dave had failed to mark his driveshaft before removal, he would have faced driveline vibrations and misalignment after the install.
Frequently Asked Questions
How do I diagnose a poor fuel injector spray pattern on an S10?
The S10 injector spray pattern can be checked by removing the air cleaner and cranking the engine while looking into the throttle body. Owners should observe the spray to see if it is consistent or if it is misting poorly. If the spray is irregular, it usually indicates a fuel pressure issue or a clogged filter.
Where is the fuel filter located on a 1987 S10?
The fuel filter is located on the engine side, mounted right next to the hot exhaust manifold. This location makes it prone to heat damage and requires frequent inspection. The 1A Auto team recommends ensuring the filter is clear of debris and is not being cooked by the exhaust.
How do I remove the fuel tank on an S10?
To remove the fuel tank on an S10, you must disconnect the filler neck, remove the 10-mm ground strap, and mark the driveshaft for alignment. A jack is then used to support the vehicle while the tank is lowered from the frame. The tank is then separated from the pump and drained for replacement.
How do I stop the fuel line from leaking?
Fuel line leaks can be mitigated by using rubber hose plugs inside the hose or by replacing the fuel filter. The 1A Auto team shows that even small leaks can be managed with these plugs as a temporary fix. For a permanent fix, ensure all hose clamps are tightened and the filter is free of clogs.
Details first shown in 20-Gallon Tank Upgrade: GM Offered It in 1987, So We Added It to Our Project S10 by 1A Auto: Repair Tips & Secrets Only Mechanics Know.