2006 5.4 3V Expedition with about 190k miles.
At 130k did a full timing set renewal. Delighted I did it, the engine has been quieter and smoother. Runs like a sewing machine, happy engine.
I didn’t stint - chains, guides, sprocket, chain tensioners, phasers, cam solenoids, and since I was in there I also swapped in the higher volume Melling oil pump, replaced the dynamic balancer (why not), roller followers (recommended) and hydraulic valve lifters. All Motorcraft parts, save the Melting oil pump.
(I had weird noises, local shop didn’t want to touch it, said drive it till it dies. I then did the full timing set myself, found one of the chain tensioners had a failed/leaking oil gasket. Come to find out the noise was from two loose spark plugs. Those loose plugs were filthy with carbon, and a subsequent “Italian water tuneup” knocked out a significant amount of carbon from the cylinders).
5k interval oil changes with Dino before, full synthetic at ~4k after.
At 160k had the transmission rebuilt (drum cracked).
Miscellaneous replacement of failed components -> throttle position sensor, Fuel Pump Driver Module (FPDM), alternator, transmission fluid lines to & from the coolers (point corrosion underneath a plastic line support, leakage noticed and replaced before catastrophic failure).
Lessons learned/recommendations -
Motorcraft timing parts are worth it (Freedom
Racing sells good kits).
Replace the FPDM as preventive maintenance after about 150k, the original design places the aluminum back against steel and corrosion will eat the aluminum until a fragment spalls and shorts the electronics. FPDM is not expensive, DIY replacement is straight forward (above left wheel well, lowering spare aids access) and the new part has standoffs so corrosion failure won’t recur.
Preventive maintenance is worthwhile - engine oil & filter, air & fuel filters , transmission fluid, diff & transfer case fluids, spark plugs, & V-belt tensioner replaced near 130k.