F150 Lariat 4 Wheel drive 97,000 highway miles.
Oil was changed every 3,000 - 4,000 miles with good quality 5W-30 oil and filter.
It has not been driven hard!
Going to drop the oil pan, inspect Rod bearings
and possably replace with oversize bearings.
Has anyone else heard of this if so how far over stock size bearing was used?

 

I have had same problem with F-150 Lariat. Experienced "ticking noise" and engine ran poorly. I have dual fuel propane on it and they say it burned out the valve seats. Compression was bad and engine ran poorly at 125,000 KM. I used synthetic oil, drove hard only when pulling a trailer once or twice a year. New hardened valve seats being put in now. They also said that propane burned out platinum plugs that I had in. Good luck...

 

Are you 100% sure that it is the rod bearings. If you hear a tapping or knocking when you crank the truck cold that last, anywhere from 10s to a few minutes you may have piston slap. A few 5.4 and 4.6 motors develop this. It is not a reliability concern, so I would definately make sure that it is the rod bearings before I but out the bucks.

 

my tapping was a rod out of place. over 4k,, rebuilt engine on it when i get it back. im the mean time i love the new 2002 dodge quad cab im renting. not torque but nice ride.