The 4.7L isn’t the Hemi, the 5.7L/6.1L/6.4L is. The 4.7L was the replacement for the old 318. It was marketed as the “PowerTech 4.7L”. It was updated several times, during it’s production run. The pre-2008 4.7L’s have one spark plug per cylinder, the 2008-2013’s have two. The modern Hemi has had two spark plugs per cylinder since it’s introduction in 2003
OP, car manufacturers make a lot of recommendations about maintenance. Many of those recommendations are more suited for a public relations standpoint rather than a what’s mechanically best standpoint.
They all do this to one degree or the other and the purpose is to try and erase as much of that maintenance cost factor from the customer’s mind as possible.
You see this with many ads for new car sales which tout “all maintenance included for 36k miles” or whatever. They’re including nothing. The actual recommended maintenance in 36k miles is very sparse and it’s built into the price.
Thank you @FoDaddy for that clarification on the 4.7L engine.
OP, car manufacturers make a lot of recommendations about maintenance. Many of those recommendations are more suited for a public relations standpoint rather than a what’s mechanically best standpoint.
They all do this to one degree or the other and the purpose is to try and erase as much of that maintenance cost factor from the customer’s mind as possible.
You ever notice the 105,000 mile recommendation for timing belt service. Seems to me that an even 100,000 miles might be a more practical, sensible number. But by reducing the required the required maintenance for the first 100,000 miles the car may seem more attractive. That and warranty requirements for up to 100,000 miles.