Cooler heat range sparkplugs of any brand will not cure the pinging in Rams,
but simply unscrewing the sparkplugs
will knock enough carbon deposits loose in the combustion chamber
that the engine will quit pinging for 500 to 1000 miles.
I was fooled many times like this and with many different sparkplugs before I understood what was going on.
Chrysler's official 'Combustion Chamber Cleaner' is about $8 per spray can and does a very good job of cleaning out carbon from the backsides of the intake valves, the piston crowns, and it you feed some through the IAC port it will safely clean that too.
In the very worse cases, unscrew the sparkplugs, spray the CCC into the eight open plug holes, let sit 30 minutes, then screw the sparkplugs back in and start up the engine and spray some more CCC in.
This does create clouds of black smoke.
If you want to experiment, do just one sparkplug hole at a time this way and you will discover which of your 8 cylinders is causing the pinging problem. Most of the time it seems to be cylinders 7 & 8 which are the back cylinders.
I have done many experiments on eliminating pinging in Magnum V8s
and the CCC treatments are what works quickly.
It is also the official Chrysler procedure.
CCC works better than SeaFoam
There is another interesting way to get rid of carbon deposits and pinging
using the water that drains out of your air conditioning.
see the 'Danger, Danger, Danger' post in the link below
http://tinyurl.com/2rb8cq
