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

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

Lift Truck Classification and Fuel Sources
There are some applications which have proved difficult for the forklift. For instance, scrap metal is among these problems. In order to successfully handle things like this requires using the right kind of machine for the job.

In this write-up, the 7 major lift truck classes are discussed, including the power sources such as liquid propane gas, hydrogen fuel cell, gasoline, diesel and electric. The power source is linked to some of these specific classes. The main power sources for forklifts comprise Diesel, Gasoline, Battery, Fuel Cell and Propane.

The most common overall are electric powered trucks, mostly in Class III, II and class I forklifts. In Classes V and IV, internal combustion trucks are more common. The most popular electric power source is the lead-acid battery. Amongst internal combustion trucks, approximately more than 90% are powered by propane.

The most popular power source for lift trucks is battery. Battery powered units make up approximately 60 percent of the new forklifts sold within the United States. Their benefits include: less maintenance requirements, quiet operation, the ability to be used outside and indoors with no harmful emissions.