Frequently Asked Questions About GMC Brigadier Truck Fuel Tank Senders

Will these fuel tank senders fit my specific GMC Brigadier model year?

Our fuel tank senders are designed to fit GMC Brigadier trucks from 1978 to 1988. However, compatibility can vary based on your specific tank configuration and capacity. Before ordering, verify your tank size (typically 50, 75, or 100 gallons) and mounting style. If you're unsure, check your existing sender's ohm range (usually 0-90 or 33-240 ohms) or contact us with your VIN for exact fitment confirmation.

What's the difference between mechanical and electric fuel senders, and which one do I need?

Most GMC Brigadier trucks use electric resistance-type senders that work with your dash gauge. These typically operate on a 0-90 ohm or 33-240 ohm range. Mechanical senders with float arms are less common in these models. To determine which type you need, check if your fuel gauge is electric (most common) or mechanical. Electric senders will have two wire connections, while mechanical units connect directly to the gauge via a cable.

How difficult is it to install a fuel tank sender, and what tools will I need?

Installation typically takes 1-2 hours and requires basic hand tools. You'll need a hammer and brass drift punch for the lock ring, a drain pan, and standard wrenches. The main challenges include safely draining the fuel tank (or working with a nearly empty tank), removing the old lock ring without damage, and ensuring proper sender arm orientation. Always disconnect the battery before starting and work in a well-ventilated area away from ignition sources.

Why is my new fuel sender giving inaccurate readings?

Inaccurate readings often result from incorrect ohm range selection, improper float arm adjustment, or grounding issues. First, verify you have the correct ohm range sender for your gauge (0-90 or 33-240 ohms). Next, ensure the sender is properly grounded to the tank and the tank is grounded to the chassis. Finally, check that the float arm moves freely through its full range without hitting the tank walls or baffles. Some aftermarket senders may require float arm bending for proper calibration.

How long do replacement fuel tank senders typically last, and what causes them to fail?

Quality replacement senders typically last 5-10 years depending on use and fuel quality. Common failure causes include sulfur corrosion from diesel fuel, worn resistance strips inside the sender unit, and stuck or damaged float mechanisms. To maximize lifespan, use quality diesel fuel, add fuel treatment regularly to reduce sulfur content, and ensure your tank ventilation system is working properly to prevent condensation buildup.