Hmmm. It sounds like your truck is in pretty good condition. Is/does the check engine light come on or flash? 1996 and newer models have the OBDII emissions onboard diagnostic system that will not only tell you if something emission related has failed, but also if something is wearing out. Since you haven't had emissions tested, there could be a posibility that something has happened and you don't know about it. If your check engine light is on, (or even if it's not) have the truck tested. Maybe you're operating outside some parameter.
The F150 displayed in my picture is a couple years older than yours, but it also has the 4.9L engine mated with a manual tranny. I tend to baby it, but it will only get max 19 or 20 on the highway. It's somewhat worn out at 148,000 miles.
Sunday, January 21st, 2007 AT 5:30 PM