S2025000008

Case Number: S2025000008
Release Date: 12/17/2020
Symptom/Vehicle Issue: Excessive Diesel Exhaust Fluid (DEF) Consumption.
Discussion: A small number of customers may comment that they are using an
excessive amount of DEF, or that they have to refill the DEF tank often.
DEF consumption is a direct result of the duty cycle operation of the vehicle. Because
of this, there are no published specifications on how much DEF a particular vehicle will
consume. The harder a vehicle is worked, especially when towing; the more NOx is
generated. To compensate for increase NOx output during high load/duty cycle driving,
the system will have to inject more DEF.
Past model year vehicles were equipped with larger DEF tanks in order to try and get
as many miles out of a tank as possible. However, due to packaging reasons, the tank
sizes were reduced on newer model year vehicles. In addition, newer model year
vehicles are also equipped with a larger Selective Catalyst Reduction (SCR) catalyst
which require more DEF consumption in order to allow more effective NOx conversion.
This combination of smaller tanks, and a larger SCR catalyst will require the DEF tank
to be filled more often.
This document does not authorize warranty repairs. This communication documents a record of past experiences. STAR Online
does not provide any conclusions about what is wrong with the vehicle. Rather, it captures all previous cases known that appear
to be similar or related to the vehicle symptom / condition. You are the expert, and you are responsible for deciding on the
appropriate course of action.
Contact STAR Center, or your Technical Assistance Center Via TechCONNECT or eCONTACT ticket if no
solution is found
FCA US LLC
Version 4.3 10/28/2020