I have a 96 F150 5.0 with 198,000 miles that does not burn oil and runs great. The engine is as clean as the day I bought it. I have replaced the belt, alternator and pulleys, flushed the tranny and performed regular maint. Any recommendations on if I should replace the plugs or other maintenance that should be done or just leave it alone. I use it 70 miles a day and pull a boat on weekends.

 

Replace the plugs, & just keep performing regular maintenance, the 5.0 is a great motor, aside from some oil leaks, they will run forever! I had one in my 1989 Mustang LX!

 

Follow the regular maintenance schedule religiously. You might find it interesting to send off an oil sample to find out how much longer the bearings & valve guides will last. There are several companies that will do it for $40-200 per sample.

http://www.blackstone-labs.com/gas_sampling.html
http://www.dysonanalysis.com/premiumkits.html
http://www.oaitesting.com./

You can probably find several more on BobIsTheOilGuy.com (BITOG).