I have a 1998 Ford F-150 with a 5.4 Tritron engine. My wife was driving my son home from hockey practise the other night. On the way over the truck drove fine. On the way home she could not go past 60 km/hour because the engine was revving high. The OD light flashed on and off continually. Also the check engine light came on. I am still waiting for my mechanic to look at it. Any ideas to help point him in the right direction. I have not driven it since.

 

Hi and welcome to the forum

After the check engine light comes on and the OD light flashes there will be a diagnostic trouble code stored in the trucks PCM (Powertrain Control Module).
The first thing to do is get it scanned and see what code caused the light to go on.
Hopefully it's something as simple as a bad vehicle speed sensor or transmission range sensor.