Update (9-18-18): Turns out the tick, ticl, tick was an exhaust noise. That got fixed which then revealed that it was drowning out the sound of the sound of some piston slap. Aint life fun? --------------------------------------- Original post 460 in my 61 f100. Engine makes a tick, tick tick noise under acceleration. VERY noticeable in the cab. Been doing this a long time, but that's not the same as a lot of miles, but I drive the truck very little, so haven't gotten around to doing anything about it. I've asked several people about the noise, people who have worked on the truck, or at least ridden in and all they say is "don't worry about it, probably nothing major". I think I might need a better mechanic or better friends or both I can't get the engine to make the noise in neutral, even when parked and revving the engine up. No ticking even when I put it in gear and rev the engine til the rear tires break loose. I tried recording the ticking today, but too much other noise in the cab. I also changed the oil and added a quart of Marvel Mystery Miracle Oil (?) thinking it might just be a sticky valve, but so far that hasn't helped. Only driven about twenty miles since though. Using a stethoscope I haven't been able to pin down a source location yet. Any Ideas?