Do you tow with the truck often or do anything other than DD? I would put the injectors in it of your for sure wanting 500+. Even of it's just something small like 155/30 or 175/30. I have never had a customer disappointed in power gains from either injector. Just depends in what you really want in the end. But definitely only use your injectors if they have that little of mileage. We actually won't do core exchange program we will only build from new or build your injectors and you get yours back. With the core exchange someone gets screwed in the end either the builder or the consumer by getting worse higher mileage injectors back.