7.3L skipping

I have a 1996 F450 7.3l. While driving at speed the motor periodically skills or stalls for a second. Each time the tach drops 500-1000 rpm. The fuel filters have been replaced. The truck has 200,000 miles. Could the turbo be failing and causing the motor to act like this? The turbo is original. I also have noticed dropping fuel economy. Thanks Joe