I've owned this truck since buying it new in June 2007, and I've done every oil change myself, always using some flavor of Mobil 1. Standard M1 at first, then the old Truck & SUV formula for a while, then, starting at around 75,000 miles or so, I've always used the Extended Performance variety. Filters have varied between Fram ToughGuard and ExtraGuard and Purolator Pure One in the beginning, to Bosch, and, in the last few years, almost exclusively Fram Ultra. The truck now has >212,000 miles. This engine has always run fantastically for me. I can't tell a difference from when it was new, and it's never needed any work. In fact, the truck has been ultra-reliable. The only work I've had to do has been u-joints (replaced all 3 when a bearing in the aft u-joint started squeaking at around 80K or so) and, recently, rear wheel bearings and axle seals, changed when the ABS/Brake warning lamps illuminated, due to oil leaking past the LH rear axle seal and into the wheel bearing housing, contaminating the wheel speed sensor. Other stuff has been very minor - a couple of idler pulleys started making noise, overhead temp/compass display had a solder joint open up and had to be re-soldered (common issue with these trucks), center console lid latch broke, etc. Still on original alternator, starter, all pumps, and the A/C still blows cold. It's never used any oil between changes, hence, my reluctance to change type/viscosity of oil. However, I've been a little concerned for the last couple of years about the increased levels of iron and chromium showing. It has me wondering about the potential cause, and if there's something I can do to cut down on wear. Blackstone says increased iron and chromium points to cylinder wear - iron being cylinders and chromium being rings. I like the even 10,000-mile intervals. I really don't want to shorten OCI. On the last couple of OCIs, time has been 12 or 13 months to get to those mileages because I bought a WRX in March 2016 and was driving that a lot instead of the truck. But, I just sold the WRX, and the Taco is now my only vehicle, so, it won't be taking me nearly as long to rack up 10,000 miles. Probably 6 months or less. My commute is 36 miles, round-trip, 4-5 days per week, which is almost all highway. I do drive pretty fast - average of 80-85 mph, probably. And, starting last month, I started taking the truck on some longer out-of-town trips that will rack up several hundred miles, at least, possibly even 1000 or more, per occasion. So, it will be interesting to see what the next UOA looks like. You'll notice that there was some fuel in the oil on this last run. That's because I do about an hour of idling per week as I sit in my truck and eat breakfast before going into work every morning. But, like I said, the higher iron and chromium numbers have me considering maybe trying a stouter oil next time. Maybe if I stick with M1, I'll just go with the 0W-40 variety and hope it does a better job of cylinder lubrication. Suggestions? Thoughts? Comments? Thanks guys.
Blackstone Comments: 23 March 2019: Aluminum, chrome, and iron are still on the high side, but at least aluminum is lower this time and iron is lower thanks to the shorter run. This engine is still wearing more at the rings and steel parts than it was in years past, so something has changed, but, at least if this is a problem, it's not getting worse in a hurry. Fuel is present, but 1.5% is just from normal use and not a fuel system problem. Stay at 10,000 miles on the oil for next time. That's give us a better idea of how chrome and iron are trending. 26 Jan 2017: This run really wasn't that much longer than past samples, so we're surprised to see wear metals increase so much. Aluminum shows piston and/or bearing wear and chrome shows a little extra ring wear. Iron is from steel parts like cylinders and rotating shafts. This could be piston scuffing, but we also can't rule out bearing wear or valve train wear. Did the engine see any harder use or perhaps get new parts installed recently? The TBN read 1.9 showing active additive left, but we suggest cutting the interval to 7,500 miles and resample to monitor. 30 March 2016: The engine has really been racking up the miles since we last saw it in 2013, but there's nothing wrong with that. Wear metals are in great shape once again compared to universal averages, which show typical wear for this type of engine after around 5,700 miles on the oil. The viscosity is at the thick end of the 5W/30 range, but that's fine. It was a little thin back in 2013 and that didn't hurt anything either. Low insolubles and silicon show excellent oil and air filtration and there's no coolant or excess fuel. Try 13,000 miles on the next oil and just check back. 18 July 2013: Iron increased a little with this longer oil change interval, but rest assured, that's a normal finding. Iron should increase with longer oil runs, since it's the only metal that tracks with time on the oil and other operational factors. Longer oil runs, harder use? More iron. The opposite is also true. As long as other metals are holding pretty steady (within a few ppm) the iron isn't making the oil abrasive, so you know you can run longer. You've not hit that tipping point yet, so add 1,000 miles to your next run. The low viscosity is harmless, and the TBN is still hanging on at 1.3. 21 December 2012: After this 7,507-mile oil run, this sample compares well with universal averages, which show typical wear for this kind of engine after about 5,500 miles on the oil. Your engine wear is right in line with averages, even after a longer run, and that's just what we like to see. Toyota engines wear well, and yours is no different. The TBN read 2.5, so there was plenty of active additive to go longer. Try 9,500 miles next and check back to establish trends for your Tacoma. Nice run.
Miles on oil: 10,322 12,236 10,996 10,158 7507 Time on oil: 13 months 12 months <4 months 6 months 5 months Miles on unit: 209,014 189,230 176,994 114,645 104,487 Sample Date: 23 March 2019 26 Jan 2017 27 March 2016 28 June 2013 21 Dec 2012 Make Up Oil Added: 0 qts 0 qts 0 qts 0 qts 0 qts Aluminum: 7 9 4 6 4 Chromium: 2 2 0 1 1 Iron: 42 61 18 24 21 Copper: 2 5 1 2 2 Lead: 0 0 0 2 3 Tin: 0 0 0 3 2 Molybdenum: 67 76 68 77 78 Nickel: 0 0 2 0 0 Manganese: 2 2 1 2 1 Silver: 0 0 0 0 0 Titanium: 0 0 0 0 0 Potassium: 5 2 0 2 3 Boron: 28 28 25 33 28 Silicon: 19 23 16 16 16 Sodium: 18 10 5 12 10 Calcium: 965 1003 1022 1085 1048 Magnesium: 639 744 891 782 714 Phosphorus: 630 683 660 695 685 Zinc: 704 803 721 803 835 Barium: 0 0 0 0 0 SUS Viscosity @ 210*F: 57.9 60.3 62.1 55.4 56.3 cSt Viscosity @ 100*C: 9.62 10.31 10.8 8.9 9.16 Flashpoint in *F: 355 400 390 405 390 Fuel %: 1.5 <0.5 <0.5 <0.5 <0.5 Antifreeze %: 0 0 0 0 0 Water %: 0 0 0 0 0 Insolubles %: 0.4 0.3 0.2 0.5 0.3 TBN: 1.9 1.3 2.5