John Deere QLS Head Unit : OEM DZ128838

Trust Your DEF Dosing: John Deere QLS Head Unit – OEM DZ128838 

What is it?
The John Deere QLS Head Unit (OEM DZ128838) is an integral part of the DEF system, installed atop the DEF tank to help manage fluid flow and monitor DEF tank status. Equipped with internal sensors, it keeps an eye on fluid level, temperature, and pressure to sustain dependable DEF operation across variable equipment usage.

Why choose this OEM Head Unit?
Designed to match John Deere's system architecture exactly, this unit slides into place via the existing DEF tank top—no rewiring or calibration required. Choosing OEM helps prevent flow irregularities, warning alerts, or poor system performance that can arise from aftermarket alternatives.

Key Benefits
✅ Exact mount for DEF system tanks on John Deere machinery
✅ Tracks DEF level, pressure, and temperature continuously for system stability
✅ Withstands fluid exposure, vibration, and temperature swings
✅ Minimizes DEF system warnings, erratic behavior, and downtime

Applications
Designed for John Deere equipment using QLS engine platforms with DEF systems—commonly found in tractors, harvesters, loaders, and stationary units. Enables consistent DEF tracking across heavy use, idle-heavy work, or harsh conditions.

Installation Notes
Power down the machine and relieve DEF system pressure before service. Remove the old unit, ensuring the DEF tank top and connectors are clean. Snap the OEM head unit into the DEF tank opening, securing it using factory fittings. Afterwards, restore power, clear any alerts, and confirm accurate DEF level and sensor feedback via diagnostic tools.

Final Thoughts
If your John Deere is experiencing inconsistent DEF readings, warning lights, or SCR issues, this OEM QLS Head Unit (DZ128838) is the direct-fit solution. Available now at Tamerx—it restores confidence in your DEF system.