First, I want to say what an exceptional source of information this forum is. The F150 owners here really know their stuff. I've owned F series Fords since 1989, and I hope to be able to contribute to this forum at some point.

I currently have a '00 F150 5.4 4x4. Last weekend we did some moderate off roading here in Colorado. On the way back home the route took us over a steep dirt road pass, prompting me to do a lot of 1st and 2nd gear power breaking. At the end of the pass, the road transitions into a 2 lane, 40 MPH black top stretch for about 10 miles into the town of Eagle. In Eagle, I stopped to top of the 1/2 full tank for the near 1/2 tank ride back to the Denver area. I ended up only putting about 6 gallons in once I saw that the price per gallon was $3.69! Within 100 yards of the gas station is the on-ramp to eastbound I-70 toward Denver. The truck started and ran just fine after fueling. While accelerating up the 1/4 mile on-ramp, I happened to look in the rearview to see that the exhaust was spewing what appeared to be white smoke, or steam. Not once did the engine miss or hesitate. I slowed, then started to accelerate again, and the white smoke stopped as quickly as it started within 1/8 mile of where it started.

I know that white smoke generally means coolant is somehow entering the combustion chamber, but wouldn't a cracked head or blown head gasket constantly leak? Further, wouldn't the problem get worse when the load increased on the engine? I never saw the smoke again, and that included driving over Vail Pass and through the Johnson Tunnel under a much heavier load than merging onto the highway at Eagle.

Could the gas I bought simply have had excessive water in it? Did all of the powerbraking (12 miles worth) cause some buildup in the cylinders that burned off once I first accelerated to merge onto the highway?

Thanks in advance for any insight!

 

Welcome to FTE!

If she isn't doing it on a regular basis or you don't notice a drop in your coolant level, I would drive on.