This is a new Cummins head unit level / quality sensor for your DEF tank. This is what pulls the fluid from the DEF tank to be sprayed into your emission system. This carries a one year warranty.

Dec 19, 2022 · This sensor should be inside the DEF tank as it has 3 jobs to do. It monitors the following items-- tank level, tank temperature, and DEF quality.

Aug 4, 2025 · I have done some reading on flushing the tank for cleaning purposes, but would like to know if anyone has had level sensor issues and was able to rinse/flush the tank with success to correct.

5511564 Genuine Cummins DEF Header Quality Level Sensor This def header quality level sensor from CUMMINS is designed to deliver reliable performance and durability.

the expert boy diagnose old bad diesel injector Pump | repaired so thats work like new pump Peterbilt with a Cummins, emissions derate due to a bad sensor. What to look for and how to fix.

Mar 15, 2025 · Knowing how to fix a DEF level sensor can save time and money. This guide will help you troubleshoot and repair your DEF sensor, restoring your vehicle’s performance.

Tamerx DEF Quality Level Sensor 90035845 for Cummins ISB 6.7L-200 is built for 2018–2022 models. Premium quality, fast shipping, and in stock.

Check engine light, sluggish performance or erratic diesel exhaust fluid (DEF) levels could point to a failing DEF level sensor. This direct-replacement sensor matches the fit and performance of the …

This OEM DEF (Diesel Exhaust Fluid) Head Unit is designed to monitor DEF level and quality in Cummins-equipped vehicles, ensuring compliance with emission regulations and optimal Selective …

Apr 21, 2024 · Archer2 has pointed out on multiple threads that some problems for the DEF sensors are the coolant line thermostats being failed open. Therefore, the DEF in the tank is getting overheated.