Dual Fuel Engine
DF or Duel Fuel Engines are the kind of engines which can work on a mixture of diesel fuel and gas fuel or it can work on diesel fuel alone. Duel Fuel engines are not able to operate on gas alone since they do not have an ignition system, nor do they possess any spark plugs.

As the engine is not a pure diesel engine and diesel is not a pure gas, this equipment does suffer from poor fuel efficiency and Methane slippage. For example, the fuel efficiency may be 5% to 8% less than in a comparable lean-burn, spark-ignited engine at 100% load. It could even be lower or higher loads.

Lift Truck Fuel Sources and Classifications
There are some applications that have proved difficult for the forklift. Like for example, scrap metal is amongst these issues. To be able to successfully handle items like this requires utilizing the correct type of equipment for the job.

There are 7 major lift truck classes, including power sources like liquid propane gas, hydrogen fuel cell, diesel, electric and gasoline. The power source is linked to several of these specific classes. The main power sources for forklifts consist of Battery, Diesel, Gasoline, Propane and Fuel Cell.

Electric powered trucks are the most popular, mainly Class III, III and class I forklifts. Internal combustion engines are more common in Classes IV and V. The most common electric power source is the lead-acid battery. Out of internal combustion trucks, about over 90 percent are propane powered.

The most common power source for lift trucks is battery. Battery fueled models make up approximately 60% of the new forklifts sold in the United States. Their benefits include: less maintenance requirements, quiet operation, the ability to be used outdoors and indoors with no harmful emissions.