Full Idea
No truth predicate is ever indispensable, because Tarski biconditionals, the equivalences between sentences and explicit truth ascriptions to those sentences, allow us to replace explicit truth ascriptions with the sentences themselves.
Clarification
E.g. 'Snow is white' is true iff snow is white
Gist of Idea
Truth is dispensable, by replacing truth claims with the sentence itself
Source
Jody Azzouni (Deflating Existential Consequence [2004], Ch.1)
Book Reference
Azzouni,Jody: 'Deflating Existential Consequence' [OUP 2004], p.16
A Reaction
Holding a sentence to be true isn't the same as saying that it is true, and it isn't the same as saying the sentence, because one might say it in an ironic tone of voice.