What would make a jeep wrangler sputter and miss going up hill under a load. Have changed the spark plugs wires rotor and cap complete tune up including Catalic Converter?
Was there a good reason to replace all of those parts? You
should start with the simple things first, such as fuel filter.
After you check the fule filter it also helped with my jeep to
check the transmission fluid. it seems to be on of the most
forgotten fluids. If the fluid gets worn out it will feel like its
sliping when put under a load. so good luck.