What is the difference between emissions-based maintenance and predictive maintenance?
Predictive maintenance uses sensor trends such as vibration, temperature and oil analysis to forecast when a part is likely to fail, so you can replace it before it does. Emissions-based maintenance measures the exhaust to see how completely the engine is burning its fuel, compares that with the engine's EPA certification record, and points to the repair that brings it back. One is about avoiding breakdowns. The other is about fuel you are paying for and not getting work from. Most fleets benefit from both.
What each one measures
Predictive maintenance watches the health of parts. Emissions-based maintenance watches the result of combustion. An engine can have every part inside its limits and still burn more fuel than it should, which is why the two methods find different problems.
What each one is compared against
Predictive models compare a machine with its own history or with similar machines. Emissions-based maintenance compares each engine with a fixed outside reference: the certification record the manufacturer filed with the EPA for that engine. The target does not drift as the fleet ages.
How you know it worked
With predictive maintenance, success is a failure that did not happen, which is hard to prove. With emissions-based maintenance, the engine is tested again after the repair. If the exhaust moved back toward target, the saving is measured, in gallons.
Where they fit together
Use predictive maintenance to protect uptime. Use emissions-based maintenance to protect the fuel budget and to give the planner a ranked list of engines worth a technician's time. The two share the same shop, the same work orders and the same crew.
Is emissions-based maintenance the same as an emissions compliance test?
No. A compliance test checks whether an engine is legal. Emissions-based maintenance uses the same kind of exhaust reading to find wasted fuel and the repair that recovers it.
Does it replace my preventive maintenance schedule?
No. Preventive service still happens on its interval. Emissions-based maintenance adds the repairs your schedule would not have found.
Who invented emissions-based maintenance?
The method was developed by Steve Forbush, a diesel technician with more than 40 years in the field, and is covered by issued United States and international patents.
Based on 3,000+ diagnostic tests analyzed on the platform.
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