timing chain or tentioners are going out again,this makes the fifth time 150,000 on 2001 Chevrolet S10

Rookie cbe0621eac06868b3efe0d8d1d3611e23c60d3114864ea2ec19a68cfbd3eebab
three different macanics have worked on it,, about time chevey pais for this one,, who would I contact for such a request,,
(1) Answer
Has it been dealership mechanics doing the work? what kind of oil change schedule do you keep with the truck ?