RT, for once we disagree. 6500 hours with proper maintance is less than 1/2 life. A mechanical survey is in order but an engine, the same age with 1800 hours could be a wreck ready for a major while the 6500 hr engine is in great health.
Maintance, Marianne, maintance counts far, far more than hours, within reason than hours. 6500 hours is within reason. I have 2800 hours on my FL 135 super, and the maintance records indicate excellent maintain economic but at 6500 hours I would not blink if all checked out.