Just wondering how everyone feels about this ,I have a 1999 F150 4x4 supercab,it getting ready to turn 55k miles,had it from new,I change oil and filter every 3k I keep a clean K&N air filter in it, Had the tranny and coolent flushed at Ford dealership in summer of 06, alls well on my OBD II autoscanner when I checked it yesterday ,Had to put a new IAC in it in 2007 and had to put rear wheel speed sensor in to ABS light was on. Truck is running fine, thinking of doing a spark plug change but should I bother since its running fine. One other thing how about gas mileage I get right around 13.5 mpg any thing I could do to improve this, this is the 5.4 engine and automatic tranny, or is this about what everyone else gets. Thanks Steve

 

Plugs should still be okay at 5k. That gas mileage sounds in the ballpark for a 4x4. It can probably be improved, but the mods needed to do it aren't cost effective unless you have to replace something anyway - like an exhaust system.

 

Thankyou for the reply