Kenworth T660 Fuel Tank Senders

Frequently Asked Questions About Kenworth T660 Fuel Tank Senders

What does a fuel tank sender do on my Kenworth T660?

The fuel tank sender is the component inside the fuel tank that monitors fuel level and sends that data to your dash gauge. It typically uses a float arm connected to a variable resistor, so as fuel levels rise and fall, the sender sends an accurate electrical signal to the gauge in your cab.

How do I know if my fuel tank sender is failing?

Common signs include a fuel gauge that reads inaccurately, jumps around erratically, stays stuck on full or empty, or fails to move at all. If your gauge behavior does not match your actual fuel consumption, the sender is often the cause, though wiring issues and gauge cluster problems can produce similar symptoms.

Will a replacement sender fit both fuel tanks on my T660?

Kenworth T660s can be equipped with different tank sizes and configurations, and sender length or mounting pattern may vary accordingly. Always check the specific tank size, mounting bolt pattern, and sender length listed for each product against your truck's specifications before ordering to ensure proper fit.

Can I install a fuel tank sender myself?

Many owner-operators and shop techs replace fuel senders themselves. The job generally involves draining or lowering fuel level, removing the retaining ring or bolts securing the sender, disconnecting the wiring, and swapping in the new unit with a fresh gasket. If you are not comfortable working around fuel systems, having a qualified diesel technician handle the replacement is a safer option.

Do I need a new gasket or seal when replacing the sender?

Yes, it is standard practice to replace the gasket or O-ring whenever you remove a fuel tank sender, even if the old one looks intact. A worn or disturbed seal can lead to fuel leaks or air getting into the system, so installing a new gasket helps ensure a proper, leak-free fit.