Not to be mean, but it is because it is a terrible engine in that application. Even with a 4 barrel it was only rated at 150hp and 240 pound feet of torque. Even the 4.3 liter V6 that came out a few years later had 130hp and 210 pound feet of torque. Thes were emission friendly economy engines. The only way to up the power is to change cams, and go to an aftermarket intake and carb or have a good rebuild on yours. The easiest thing to do if the motor is tired is to replace it with a good 350.
Weight capacity would be a time for low estimate, like on an elevator or pulling power for a truck.
It could be anything from the engine to the connectors
change the fuel filter
You could put a banks turbo on it if you wanted it would give you more power. Its a work horse engine designed to tow and move a truck around. Its no sports car. its a truck.
It would have to be licensed as an RV.
Belt
Stronger meaning? If you mean pulling power that depends on the engine under the hood. If you mean how they're built then I would say they are about equal. Both Dodge, Ford, and Chevy are all great trucks. Ford is the number one selling truck if that is an indication of anything.
NO. That means the engine is running too hot. Check cooling system.
Unless you need lots of towing power, I would opt for the 5.3. A very good engine.
i have a 1998 ford expedition and i had simaliar to the same problem. does it feel like your loosing power? on my truck it was a misfire on my engine coil i would get that check out
Do you want to have no power at all? The M11 is a vocational truck engine... the way the truck is geared with the C15, I seriously doubt you want to stick an M11 in there. Not only that, but that's a post-ACERT truck... you can't put a pre-ACERT engine in it legally unless the truck was purchased as a glider kit.
The first place I would look is at the timing, a vacuum leak will also have this effect on an engine.