Alright, I changed the oil today, about 670 miles after the last change. The oil still looked quite clean on the dipstick, but came out black. This tells me that the oil is doing its job to clean the vast amounts of sludge out of the crankcase.
The amount of metal contamination in the filter has vastly reduced since the last change - I really had to look hard to spot any metal, and the metal that was there was much finer than before. This is super encouraging, and tells me that the metal has most likely been in there for a while and isn't something I should be too concerned about.
I changed out the old Quaker State 10W-40 with the recommended 15W-40 Shell Rotella, and I can't believe how much better the engine sounds now. There is basically no ticking under 2,000 RPM now, and the engine sounds much happier in general, with lots of other engine noise now much quieter. It sounds great. That mechanical oil pressure gauge I installed a few months ago acts like a stethoscope, so you hear even the faintest of ticking loud and clear from inside the cabin, but there really isn't any noise below 2 grand (on that note, don't install a mechanical gauge if you can avoid it. After all of the fittings and copper line for my mechanical one, I wasn't too far off from the price of a digital one, which is much quieter, less likely to leak, and easier to install. Learn from my mistakes - go digital). There is still some ticking above 2,000 rpm, but it isn't as loud as it was before. With the slightly heavier weight oil, pressure has increased 1-3 psi across the board as well (it's still on the low side though - 51 cold idle, 9-11 hot idle, 53-54 cold 2k, 37-39 hot 2k). I've only taken it on a short drive to the gas station, but it might make a little more power now as well.
Overall, I'm very happy with the results. I'll keep changing it with the same 15W-40 Rotella, probably with 500-mile intervals. I'm hopeful that the Rotella will help clean out some of the stuff that the cheap oil couldn't, and possibly give me a silent, tick-free engine. Time and miles will tell. I'll report back with any new developments.
The amount of metal contamination in the filter has vastly reduced since the last change - I really had to look hard to spot any metal, and the metal that was there was much finer than before. This is super encouraging, and tells me that the metal has most likely been in there for a while and isn't something I should be too concerned about.
I changed out the old Quaker State 10W-40 with the recommended 15W-40 Shell Rotella, and I can't believe how much better the engine sounds now. There is basically no ticking under 2,000 RPM now, and the engine sounds much happier in general, with lots of other engine noise now much quieter. It sounds great. That mechanical oil pressure gauge I installed a few months ago acts like a stethoscope, so you hear even the faintest of ticking loud and clear from inside the cabin, but there really isn't any noise below 2 grand (on that note, don't install a mechanical gauge if you can avoid it. After all of the fittings and copper line for my mechanical one, I wasn't too far off from the price of a digital one, which is much quieter, less likely to leak, and easier to install. Learn from my mistakes - go digital). There is still some ticking above 2,000 rpm, but it isn't as loud as it was before. With the slightly heavier weight oil, pressure has increased 1-3 psi across the board as well (it's still on the low side though - 51 cold idle, 9-11 hot idle, 53-54 cold 2k, 37-39 hot 2k). I've only taken it on a short drive to the gas station, but it might make a little more power now as well.
Overall, I'm very happy with the results. I'll keep changing it with the same 15W-40 Rotella, probably with 500-mile intervals. I'm hopeful that the Rotella will help clean out some of the stuff that the cheap oil couldn't, and possibly give me a silent, tick-free engine. Time and miles will tell. I'll report back with any new developments.