help with pinging noise, also cooling ??

[ryanmcb]

I recently purchased an 89 Suburban for my family. Very well maintained, original owner, 73k original miles. The guy gave me a perfect service record from the time he bought it.

When I climb a hill the motor starts to ping, only on inclines under load. I have tried high octane fuel and it does not solve the problem. I thought the computer would adjust itself and time the ignition correctly over time but it continues to ping.

Are there any suggestions? Should I manually time it? If so, how do I disconnect it from the computer? Should I be looking at something else, maybe I am not identifying the right sound? I am taking a trip this week to the mountains and would love to resolve this issue.

One more thing, the truck runs a little warm, more than I like. Do you guys use 180 or 160 Tstats? I believe it has the stock 190 in it right now.

Thank you!