1971 Chevrolet C10 — Replacement Fuel Sender (40-Gallon Tank)

Vehicle & Part Overview

The 1971 Chevrolet C10 with the 40-gallon tank option requires a sender unit that is different from the standard 20-gallon setup. The 40-gallon was an optional auxiliary-style tank on these trucks, meaning the sender's float arm length and ohm range will differ from the more common unit.

Ohm range: GM fuel senders of this era typically run 0 ohms full to 90 ohms empty. Verify this against your gauge cluster before purchasing, as some aftermarket gauges expect a different range.

Confirm which tank you have before ordering.

Sourcing Recommendations

  • Classic Industries — carspanner.com/go/classic-industries
Specializes heavily in C10 and full-size GM truck parts; should carry the correct application-specific sender for the 40-gallon setup.

  • Ground Up Truck Restoration — carspanner.com/go/ground-up-truck
Focuses exclusively on Chevy and GMC trucks of this era; often stocks harder-to-find 40-gallon tank components.

  • Brothers Truck Parts — carspanner.com/go/brothers-truck-parts
Strong C10 specialist with good coverage of 1967–1972 trucks; a reliable fallback if the 40-gallon-specific unit is unavailable elsewhere.

Fitment & Safety Notes

Flange pattern: When removing the old sender, note the number of mounting bolts on the lock ring. The 40-gallon tank on the C10 used a different flange pattern than the standard tank. Match this up before committing to a purchase.
Float inspection: Shake the old float near your ear and listen for sloshing. A waterlogged float — caused by pinholes — will produce a permanently low fuel reading and should be replaced along with the sender unit.