Arborvitae turning brown and dieing Help

[DaddyHandyMan]

I live in Indianapolis and I planted arborvitae 3 years ago last year a number of them turned brown and died on me. I though that it may have been from the heat. Now I'm thinking that it may have been from grubs.

Already this year the remaining bushes are turning on me. Can I save them or should I just replace them with something else???

Any help with this will go a long way....