Here's a general outline of the process. Specific steps may vary slightly depending on your truck's configuration and the type of sending unit you're installing (aftermarket vs. OEM). Consult a repair manual specific to your 1995 Chevy S10 for detailed instructions and diagrams. A Haynes or Chilton manual is a good investment for this type of work.
1. Preparation:
* Safety First: Disconnect the negative battery cable. Work in a well-ventilated area away from any ignition sources. Have proper tools and safety equipment (gloves, eye protection).
* Gather Tools: You'll need sockets, wrenches, screwdrivers (possibly Torx), a fuel pump pliers (to disconnect fuel lines), a fuel line disconnect tool (if needed), a new fuel sending unit gasket, possibly a new fuel filter, and possibly a tank strap wrench (depending on tank access). You might also need a helper for supporting the fuel tank.
* Drain the Fuel Tank: This is critically important to reduce the risk of fire and spillage. Siphon the gas out using a siphon pump and store it safely.
* Lower the Fuel Tank: This is the most challenging part. The procedure varies depending on the access to the tank; some S10s require dropping the tank entirely, others might allow access through a smaller hole in the bed. You'll likely need to disconnect the fuel lines, the fuel tank electrical connector, and possibly the tank straps. Support the tank as you lower it to prevent damage.
2. Replacing the Fuel Sending Unit:
* Access the Sending Unit: Once the tank is accessible, locate the fuel sending unit. It's usually located on top of the fuel tank.
* Disconnect the Electrical Connector: Carefully disconnect the electrical connector from the sending unit.
* Remove the Fuel Sending Unit: You might need to unscrew the sending unit from the tank using a wrench or socket. There will likely be a retaining ring or clamp.
* Install the New Gasket: Install a new gasket on the fuel tank opening before installing the new sending unit.
* Install the New Fuel Sending Unit: Carefully install the new fuel sending unit, ensuring it seats properly.
* Reconnect the Electrical Connector: Securely reconnect the electrical connector to the new sending unit.
3. Reassembly:
* Raise the Fuel Tank: Carefully raise the fuel tank back into its position, ensuring all connections are secure. Reconnect the tank straps.
* Reconnect Fuel Lines: Reconnect the fuel lines using fuel line pliers or a specialized disconnect tool, ensuring tight connections to prevent leaks.
* Reconnect Electrical Connector: Reconnect the electrical connector to the fuel pump module (if separated).
* Reconnect Battery: Reconnect the negative battery cable.
* Check for Leaks: Inspect all connections for leaks. Start the vehicle and check the fuel gauge to ensure the sending unit is functioning correctly.
Important Considerations:
* Fuel System Pressure: The fuel system may retain some pressure even after draining the tank. Release any remaining pressure before disconnecting fuel lines.
* Fuel Tank Safety: Fuel tanks can be heavy and awkward to handle. Use appropriate lifting techniques and get help if needed.
* Proper Torque: Tighten all bolts and nuts to the manufacturer's specified torque, as listed in your repair manual.
This is a general guide. Refer to a repair manual specific to your 1995 Chevy S10 for detailed instructions, diagrams, and torque specifications. If you are not comfortable performing this repair yourself, take your vehicle to a qualified mechanic. Working with fuel is dangerous, and improper installation can lead to serious consequences.
