my friends 96 dodge ram 5.9 v8 360 has problems coming up a steep hill

almost every time but not every time it will start sputtering and the check engine light will start flashing.

it will make it up the hill but it has trouble

on the flat roads it works fine even the freeway its perfect
only on the hill do i have problems

i checked the engine code and it says random misfires
misfire cylinder 1
misfire cylinder 2
misfire cylinder 3

i have new spark plugs

is it my cat?

i have new spark plugs
New Autolite spark plugs?

yes they are autolite

Just make sure you check the ignition coil terminal to make sure it's not corroded and if it is corroded then clean it with sand paper.