Truck repair

hi every body i have a 1987 ford 350 when i go up a steep hill the truck starts to skip and break down to a point where ihave to pull over i just put in new fuel pump in tank ,what could be the problem only happens on hills thanks

What engine in the F350?


Could be a variety of things. Short of selling to some unsuspecting soul who lives in Texas, I would drive it to a competent mechanic…( with a location that doesn’t require you to drive up a steep hill)

Does it have a carburator?

A weak ignition coil can cause this, plugged fuel filter, if it has a cat that could be clogged.

thanks for reply yes it has carb with 4.7 (460) masonary dump

Have you been using gasoline that contains ethanol in the vehicle?


I had an '86 F250 with the 460 engine, and the carburetor had all sorts of vacuum line spaghetti for emissions control. Check all the vacuum lines for cracks. Also possible you need a carburetor rebuild.

I’d check the float to see if it’s in need of adjusting. What happens when it dies on the hill? How do you get out of the predicament? Coast backwards to the bottom of the hill?

If fuel pressure and volume are adequate the problem is likely in the carburetor. My look up indicated a Holley 4bbl with a vacuum secondary. That’s not technically complicated but it is very busy. If you aren’t comfortable opening it up find an old mechanic familiar with it. If the bowl vent hoses are off I wouldn’t be surprised if sediment were preventing the floats from dropping far enough to supply adequate fuel at wide open throttle. It was described as a masonry dump and that leads me to assume that it sees a great deal of dust and dirt.

On the offchance that the problem is not related to the fuel system, there’s also the possbility of an overheating TFI module which I’m reasonably sure this model uses.

Maybe the engine temp is rising due to climbing a hill. Combined with summer heat and the notoriously iffy modules maybe the module is going stupid.

I’ve had a TFI module act up on me in CO a few times during the summer and usually at the top of a mountain pass after a climb and higher than normal engine temps.
Just something for consideration if the potential fuel issue doesn’t pan out.

I would suspect that ethanoll has eaten away most of your carbs tiny parts, or that you have a vacuum leak that opens as the weight shifts going up hill.

when I rebuilt the carb in my 75 ford with a 360 motor, almost every little part and diaphragm in the thing was no good, some little spring type parts had rusted completely away.

amazingly, it still ran.