No some loud trucks are gas spark engines so they are sometimes louder.
80% of all trucks are desil
no
yes. Not all trucks are loud if you cut off some of the muffler then the truck will become louder
NoNo
No
they can, or you can customize it.
All modern ones are, yes.
Two stroke diesel engines have been manufactured for many years, Detroit have made them for use in loading shovels and dump trucks and foden trucks in England made a two stroke in the 60's for their trucks, they are by modern standards loud, thirsty and dirty.
Some trucks are so loud because of poor synchronization.
no diesel is used in trucks. like buses or truck driving trucks
You can find used Diesel trucks for sale at http://www.dieseltraderonline.com/. Also try http://www.handpickedtrucks.com/diesel-pickup-trucks-for-sale.html and http://www.dieselland.com/
Gas is better to use than diesel for trucks for offroading.