Threatening to take business elsewhere *may* get you covered until something happens and they just sting with a claim denial then. Really...so it's only a 6 ton truck with bed, frame, axle, brake, and tire size modification? Sometimes the insurance companies aren't just being spiteful pricks. Then, for argument sake, they cover you as you hypothetically met some qualification that made them feel good and then an accident occurs which goes to litigation. Huh, oh you never got a reconstructed title for you modified frame? Bye-bye...