Detonation ping

[Rednek13x]

Ever since Iv owned my truck it would always just randomly should to make this rattling noise while driving down the road. Always thought it was a power steering pulley or something. And then this sprig it started to do it all the time so I started to look further into it. It really did it under load, i run pump 87. My truck is a 1983 c10 305 3 speed colum. All stock. Has 136,000 miles and I daily drive it 100 miles a day.

What I ended up doing was hooking up my vintage 10foot camper to it and pulled it down the road. Once warmed up sure enough it started making this god aweful rattle. So I unhooked and drive the truck a few days until the tank was empty. Then filled with premium 91 and dumped in some octane boost. Hooked up the camper and pulled it down the road and it never made a rattle. So I believe that's what's going on.

Iv tried adjusting the timing all over the place. The best seems to be 4deg at idle with the vac plugged off. That's where it's at now.

All summer Iv just been burning the 91 and havnt really had an issue. Just expensive.

Iv noticed it happens more when it's cooler out, it's getting into the 50s in the mornings and it's actually starting to what I think is ping even with the 91 octane in there.

Does this sound like an detonation issue, why in my soggy 305 does it seem like like a higher octane, even with a lousy timing. Why does colder weather effect this.

Winters coming and I'm driving the truck till the snow falls. Help me get this figured out before I loose a piston.