Chevy Pickup Rod Knock
1996 Chevrolet Silverado C1500 with a 305 (5.0 liter) and only 56k miles. I need some input on a rod knock that has surfaced recently on my Chevy pickup. Actually, I've had this for a few years, but it never was as bad as it currently is. Its moderately loud when the engine is cold, but will disappear after a few minutes of running. Its more noticable during colder temps, and on a warmer day 40+ degrees, its only there for a few seconds.
Now, I'm sure its a single rod knock because it only happens under load & is rhythmic with engine speed. Oil pressure is excellent: 60 psi @ cold idle, 20 psi hot idle. I know what multiple knocking sounds like from poor oil pressure when cold, and its definitely ONE rod.
I think the pan could be dropped & the rod bearing replaced with the engine in the truck. If I go this route, I'm thinking of pulling a spark plug each time at cold restarts to isolate the bad rod, which may take eight attempts.
What would I expect to find when I disassemble? A scored bearing or a broken/split bearing? Could this solitary bearing simply be not getting enough oil when its cold?
Thanks for any and all input!