I just had my engine replaced in my 97 f150. V6 4.2L. 160K. It was, of course, due to the faulty front head gasket that seems to be a problem for many 96-97 engines like mine.
I had it replaced with a Ford factory rebuilt engine. I have 3 yr./36,000 warranty on the engine, but received no instructions to breaking in the engine other than changing the oil at the first 1,000 miles.
Now that I have a new engine, is there anything I can do to improve its performance? I like the truck, but the engine is, and was, always a disappointment to me.
I just filled my second tank with gas since the new motor, and got a whopping 13.8 mpg, and the majority of my driving is rural and highway. (80%). Is this normal? Can I do anything about the mpg and the power, (or lack thereof)?
I know it's a 6 cyl., but the 4.6 v8 out performs my 4.2 in both areas.
Of for the days of the 300 straight 6!

 

Wow, I drive mostly city with a 98 4.6 with auto and get 15-16 MPG. The power is still not great, esspecialy when towing, then my mileage drops to 11 mpg. (~4500 lb trailer) I have a freind with a 4.2 and stick, I should see what he gets.

 

My 97 4.2,auto, gets 18-21 mpg highway,15-17 city mpg.

 

You should give the motor time to 'break in' before worrying about mileage. atleast 10,000 miles.

If you dont mind. how much was the motor and install?

 

the motor was $2300 (motorcraft). install was $750.

 

Thats cheaper than a rebuilt motor!! So it was a complete new motor?

 

it was complete engine, from manifold down, excluding electrical, oil and plugs. it's remanufactured by Ford, w/3 yr. 36,000 miles at any Ford Authorized Service Center anywhere. I thought it was a good deal, but I'm still disappointed in the engine. I was hoping somebody could lead me to a way to increase mpg's. Maybe I should give it time to break in.

 

You got a good deal. wish i would have done that!