I have a 2005 F150 5.4 with 96,000 miles on it. I have never had any issues with it and I have had it since it was brand new. All of a sudden, Sunday, it started making an odd noise. When I checked it was dangerously low on oil. We went ahead and changed it and now it's using gas like mad. Any suggestions what to check?

 

I don't know if that model has a PCV or an orifice. Change the PCV is it has one. See if you can clean the orifice if that is what it has.
Did you buy it new?

Some people don't bother to change the oil in leased vehicles and the next owner pays the price. I bought one of those a long time ago. Hadn't had an oil change in the first 29k miles. I learned to check the engine for cleanliness after that experience. That particular engine was full of sludge.

 

I bought it new in November 2005. My son races motorcross so we change the oil and keep the tires rotated. This is the first issue with it. I had to put in in 4WD Saturday and Sunday at the track because of the mud to get in and out and then this suddenly started. But we'll check it out. Thanks for the suggestion.

 

Have the plugs been changed? How about general maintenance such as fuel filter and air filter? I would also check the injectors for leakage and I would do it quickly. The 2005s had some injector problems that can lead to a hydolocked engine.

 

My 07 started burning oil like that when my timing chain tensioner seals were bad, also made a lot of noise on startup and around 800-1000 rpm. I replaced all the timing related components and haven't been using any oil now. Still on my first oil change since then but I was using a quart every couple days. Just throwing that out there as an idea

 

5W20 oil gives to best MPG. heavier the oil, the less MPG ! Also your front wheels may be still in 4wd because of a Vac leak?? real bad MPG!

 

My 05 has been using oil the last few oil change cycles used about 2 quarts in the last cycle. I have little over 177k on the truck now this oil useage started around 165k.

 

Leaking fuel injectors can cause the oil to be washed off the cylinder walls and scour the cylinders. The 2005 injectors are still under warranty within a certain mileage I believe because they were prone to leaking. Leaking injectors could explain both issues of oil consumption and high gas consumption.