I have a 1997 dodge ram 4x4. I hear pinging when I am on a incline, when I give it gas is feels like a lose a few cylinders ( the hole truck starts jumping )

Ensure you are only using the same Champion spark plugs, or the next colder plug, that originally came in your Ram. Rams often destroy other brands of plugs.

Since you are experiencing engine knock, you can also try filling up with the next higher grade of gasoline every other tank. Installing colder running plugs is, obviously, a cheaper solution. Using the proper weight full synthetic engine oil also helps.

OK but what causes the feeling that I lose a few cylinders when I give it gas when it is pinging? Other wise it runs good

Spark plugs breaking down under load or wrong heat range? A compromised ignition system?

Have you tried using higher octane gas, yet?

Did not get any gas yet. How can I tell which spark plug to get in the way of heat range? Also what would cause the ignition system to change?

Try contacting Federal Mogul, manufacturer of Champion spark plugs.

Worn out plugs, spark plug wires, coil, Ignition Control Module. Wipe the spark plug wires down with silicone spray--they may be shorting out under load.

Changed plugs and put in higher grade gas. No change . Anything else I can try?

Did you install colder running Champion spark plugs? Next, try replacing the spark plug wires and coil.

Replaced wires , rotor, cap. plugs, higher grade gas, new fuel pump. Next trying coil maybe pull carb and look at that.. can the timing be changed or does the computer control it.

Did you try colder running plugs?

Timing is controlled by the PCM. Replacing the Camshaft Position Sensor and Crankshaft Position Sensor may also improve performance.