Simplify the following text for a Grade 9 native English-speaking person.
Original: The world 's first production turbo diesel automobiles were the Garrett-turbocharged Mercedes 300SD and the Peugeot 604 , both introduced in 1978 .
Simplified: The first production turbo diesel automobiles were the Mercedes 300SD with a Garrett turbocharger , and the Peugeot 604 . Both were introduced in 1978 .