08' F 150 5.4L V8
99,750 mileage
have used synthetic oil 5 - 30 since new, runs great
uses a quart every 6 months
only do about 6K miles a year, change oil every April * October(every 6 months)
already have an amsoil oil filter
you guys are smarter than me - suggest a full synthetic
THANKS

 

Might as well keep using 5w30 synthetic. If you are looking for an alternative to Amsoil, I use Mobil 1 EP.

 

Assuming that you are not racing, or doing a lot of heavy towing....... just about any brand of synthetic oil will work for a year. Many would say that you could simply use synthetic blend, as in the OEM motor oil.

In 16 years, and almost 100,000 miles, you have been doing okay. Just keep doing what you're doing. No need to change.