Donaldson Diesel Exhaust Fluid (DEF) Filters

Diesel exhaust fluid filters protect the SCR dosing system that meters DEF, also sold as AdBlue, into the exhaust stream. DEF is a precise urea solution and the dosing components that handle it have very fine clearances, so particulate or crystallised urea in the fluid can block or damage them. Repairs on that side of the aftertreatment system are not cheap.

DEF also degrades with heat and age and will crystallise around any fitting left open to air, so clean handling matters as much as the filter itself. Search by Donaldson part number, or give us the engine or dosing system details and the number from the existing filter.