2001 Dodge Ram 1500 4x4 360 Pinging going up hills

2001 Dodge Ram 1500 4x4 360 with 96 000km (pinging problem)
As soon as I go up a hill (or load on the engine) my engine starts to ping like crazy. Only satrted doing it about a month ago. Ever since I bought the truck a couple of months ago the truck has a bit of a rough Idle. I put a single inlet dual outlet Flowmaster series 40 on and dual exhaust from the muffler and around the same time i installed the new muffler I noticed more that the engine was pinging. It may have been doing it before but I just never noticed. If I burn supreme it is this pinging but not near as bad.
The problem with it Idling rough I've been told is a bad fuel pump, I'm not sure if that could be it or not.
My check engine light is not on.
"Any suggestions would be great"

Try running high test gas and adding a octane boost to it. It had the same problem with me 99.

YOU ALSO MIGHT WANT TO GOTO AUTOZONE OR A SIMILAR AUTO-PATRS STORE AND GET SOME BERRYMAN B-12 CHEMTOOL. NEXT TIME YOU ARE EMPTY & AT THE PUMP, PUT THE WHOLE CAN IN BEFORE YOU FUEL. IT IS A GREAT FUEL SYSTEM CLEANER AND IT MIGHT DO YOU SOME GOOD, MIGHT NOT. BUT, IT WONT HURT TO INSURE THE SYSTEM IS CLEAN.

Pinging means there's something wrong with the motor, probably due to messed up emissions equipment.

My truck pings so loud that it's embarassing. I took it in to see if I could have it fixed and nothing helped, so I decided to just leave it, and run it anyway.

You might check into the gasket sealling the plate to the bottom of the intake manifold. These gaskets are very, very, vvvvvveeeeeerrrrrrrryyyyyy notorious for leaking and causing this engine to ping.

Berryman B12 is a good answer, if it doesn't help you, then it might be time to tear the motor down and rebuild it. I suspect it's NOT the fuel pump. Maybe head gaskets, worn camshaft, carbon deposits on the pistons, low compression.

It could be anything. B12 will settle your fuel delivery trouble (usually), then it's a cat and mouse game....

I had a similiar problem with my 96. It turned out that one or two of the injectors were clonged. It might be something to check out.