Semi-Truck Losing Power or Going Into Derate?
Your Aftertreatment System Is Already Under Stress
If your semi-truck is losing power, going into derate, or forcing regens too often, the problem is not going away on its own.
In most cases, this means your aftertreatment system is under stress. The DPF may be restricted, the DEF system may not be dosing correctly, or sensors are feeding incorrect data to the ECM.
Every mile you continue driving increases exhaust backpressure, engine stress, and the risk of a full shutdown.
đź“ž Call Now for Immediate Diagnostic
214-761-9082
Why Your Semi-Truck Goes Into Derate
A semi-truck enters derate when the ECM detects a problem in the aftertreatment system that could damage the engine or violate emissions limits.
- DPF soot buildup and restriction
- High exhaust backpressure
- DEF dosing failure
- NOx or temperature sensor faults
- Failed regeneration cycles
Common Emissions System Failures
Most emissions issues come from a few critical components:
- DPF clogged or overloaded
- DEF injector or pump failure
- Sensor misreadings causing false derate
- EGR malfunction increasing soot production
- Electrical or wiring faults
What Happens If You Keep Driving
Driving in derate increases risk fast:
- Severe power loss
- Fuel inefficiency
- System overheating
- Forced shutdown
- Complete breakdown
Why Regen Does Not Fix the Problem
Forced regen only burns soot temporarily.
If the issue keeps coming back, the root cause has not been fixed. This often leads to repeated downtime.
How We Diagnose Emissions Problems
At Salazar Semi-Truck Repair Inc., we perform full system diagnostics:
- Dealer-level computer scan
- Live sensor data analysis
- Backpressure testing
- DPF and DEF system inspection
Same-Day Emissions Repair in Dallas TX
We repair:
- DPF systems
- DEF dosing systems
- Sensor failures
- Aftertreatment system faults
Serving Dallas–Fort Worth Area
We help owner-operators and fleets across Dallas, Irving, Arlington, Grand Prairie and surrounding areas.
Do not wait until it shuts down.
Call 214-761-9082 now
Semi-Truck Emissions & Derate FAQs
A semi-truck goes into derate when the engine control module detects a problem in the aftertreatment system, such as a clogged DPF, DEF dosing failure, or faulty sensors. This reduces engine power to prevent damage and emissions violations.
You can drive for a limited time, but the issue will worsen. Continued driving increases exhaust backpressure, engine stress, and can lead to a complete shutdown, requiring towing and costly repairs.
Frequent regen cycles usually indicate a deeper problem such as excessive soot buildup, sensor inaccuracies, or a failing DEF system. A forced regen will not fix the root cause.
DPF clogging is caused by excessive soot accumulation due to incomplete combustion, failed regen cycles, faulty injectors, EGR issues, or incorrect sensor readings.
No. A forced regen temporarily burns soot but does not fix underlying issues such as sensor failures, DEF problems, or restricted flow inside the DPF.
Common signs include derate warnings, check engine light, poor fuel efficiency, excessive regen frequency, and error codes related to dosing or fluid quality.
Your Truck Is in Derate Right Now?
Loss of power is only the beginning. This can turn into a full shutdown, towing, and missed loads within hours.
Stop the downtime before it escalates. Dealer-level diagnostics. Same-day repair decisions. Serving all DFW.