There are several factors that contribute to this stretching, some of which are serious problems that can be addressed through upgrades of their own. The best way to prevent head gasket failure on the 6 L is to install ARP Head Studs preventively.
A linguist is someone who studies language. Linguists study every aspect of language, including vocabulary, grammar, the sound of language, and how words evolve over time. The study of language is called linguistics, and people who study linguistics are linguists. Being a linguist isn't easy; you usually have to go to graduate school and conduct research about a specific aspect of language. There are computational linguists, forensic linguists, comparative linguists, and many other specialties.
The word grammar tends to have two very different definitions. The first is the one given by linguists, the people who study language scientifically. They define grammar as the way speakers of a language assemble words to form phrases, clauses, and sentences. This understanding of grammar is concerned not with how people are supposed to use language but with how they actually do use language. The second is the popular definition, the one that most of us probably learned in school: a collection of perceived rules about the right and wrong way to use language.