This is my first ever post on this forum or any forum for that matter. I have an 87 Comanche 4.0 pioneer that has a bad ticking noise. It has been doing this noise for the last 6 months I've owned the truck. I've run thicker weight oils, various additives and they did little to help. The noise is strange in that it is intermittent and only seems to get bad after the engine is fully warm. Did the rear main seal two months ago and didn't notice any metal debris in pan. It doesn't get noticably audible until oil pressure is under 40. Seems to be worse at idle(or just easier to hear) or when coming to a red light after driving at higher speeds. I have had two people listen to it and one believed it was most likely a bad lifter. The other seemed to think it was a possible exhaust issue. I believe that I do have some exhaust leak, but I don't think it could be the cause of metalic click noise. I am leaning toward it being the lifters, but I also know these engines can develop piston slap. Before I get into any fixes is there anything that can be done to help determine if the tick is a lifter, piston, or possible exhaust? What do you guys think it sounds like?
I have attached a short clip of the engine ticking when fully warm. Thanks for any advice you may have.