None. Diesels don't use plugs.
Internal combustion.
Need to know which type, gasoline, diesel, electric or steam engines.
Straight/Inline engines, V type engines, Rotary engines and diesel engines
The C classification of oil is for diesel engines.
Diesel trucks don't use spark plugs, they use glow plugs. For your tuck i don't know ecpesifcally which glow plug you need cause you never mentioned what your truck is.
gaspropane Diesel engine
There are a number of different types of car engines. Some of these engine types are Straight/Inline engines, V type engines, Rotary engines and diesel engines.
Diesel is a type of fuel used in diesel engines. It is a petroleum based fuel. In the UK it is called DERV and in Australia it is known as distillate.
Well this all depends on what type of engines are supplied in these buses. Usually buses use diesel due to the high weight load that that are put on the engines. Diesel engines have better compression and can usually provide more torque to do work with all those people on board. Here is a good read on Diesel engines....(link)
Gasoline or diesel engines are compatible with Banks Power exhaust systems, depending on the type of exhaust system purchased. Most of their products are for Jeep, Ford and Dodge diesel engines.
Type of combustion is determined by the engine, not the fuel. Intermittent or reciprocating engines such as those found in cars and trucks can run on diesel. Gas turbines AKA jet engines can also run on diesel however they are continuous combustion engines. The answer to your question depends on the type of engine you have in mind. If it has pistons then it will be intermittent.
Need one...no, BUT HIGHLY RECCOMENDED!!! Without some type of gasket, you will go through either lots of oil, or lots of engines!