There's a little more to it than that... gap between gears, power-to-weight ratio, and overall drive ratio of the transmission, rear end gears, and tire revolutions per mile all factor into it. Plus there's the engine itself... when you say six cylinders, you could be talking about an old Ford 3.0, or a semi truck engine (they use an inline six engine, typically displacing 13 to 16 liters).
Fo course not. Modern 6 cylinder and even 4 cylinder engines have more power than V8 engines of the past.
More info (year, make, model) would be helpful but if the engine and vehicle is well maintained and not overloaded, it should have no problem.
You probably have a 4 cylinder engine (A.K.A. the V4 Engine), V4 engines aren't very powerful, I previously had a V4 and I had the same problem.
it is both kinetic and potential energy
Gravity.
Engine is in need of tuning.
its getting ready to explode. jump out quick
Time for a tune up.
With a forklift, carry the load on the uphill side.
It depends how high you're talking about. If you mean revving all the way to the red line then yes this is bad for the engine. But the rpm shouldn't exceed 4000 rpm. If it is slightly below this then it is fine.
You're driving an automatic, the car should select the correct gear for you. However some automatics allow the driver to select low gears for use in slow moving traffic for example. If you feel you need more power when driving uphill then select one of the lower gears.
A Ford Ranger may die going uphill due to ignition problems. There could also be a problem with the fuel injection or fuel pump.
because it is going uphill and the engine has to work harder?
Automatic transmissions lose acceleration driving uphill because of the torque converter. The engine turns one side of the torque converter and the other side is splined into the input set of the planetary gears. The torque converter uses fluid to turn the input shaft in the transmission. When the transmission is locked into gear and going uphill the torque converter has to work against power losses from the tires on the road and when the engine is working harder the torque converter cuts or "shears" the fluid and it causes the transmission to overheat. Always make sure you have enough fluid in the transmission