The following is the latest UOA on my 2015 Toyota Tacoma 4.0 V6. This oil was in use for 7.5 months, almost 10,000 miles. This nearly doubled my last UOA interval, and is double what the manufacturer recommends. Some interesting things in this UOA.
First, some things that were flagged, but not surprising: Copper is still high, but is trending down. I believe the copper is coming from the engine oil cooler, which this engine has as a part of the towing package. Also, Silicon is still high, but still trending down on a per-mile basis. I have seen this on many Toyotas that I have bought new, like this one, and I believe it is coming from the sealers Toyota uses in the engine.
Some other notable things: I was rather surprised that the viscosity was slightly high - virgin VOA is about 10.5. Also slightly surprised that insoluables went from 0.1 to 0.3. The oil filter used was a Mobil 1 M1-209. TBN and TAN look pretty reasonable to me.
I think Iron overall, although normal, is higher than what I typically see on most Toyota engines...I suspect the engine is not 100% broken in yet, I may have jumped the gun on going to a 10K miles UOA interval.
Blackstone commented that "perhaps the oil got hot" - We did not tow anything during this interval, the heaviest load consisted of 4 passengers on a highway trip. During this interval, the truck was used for about 35% highway driving, 65% city/suburban driving.
Comments? My plan is to do another 10K miles interval. The oil was changed and Amsoil signature 5W-30 was used again for the new interval.
First, some things that were flagged, but not surprising: Copper is still high, but is trending down. I believe the copper is coming from the engine oil cooler, which this engine has as a part of the towing package. Also, Silicon is still high, but still trending down on a per-mile basis. I have seen this on many Toyotas that I have bought new, like this one, and I believe it is coming from the sealers Toyota uses in the engine.
Some other notable things: I was rather surprised that the viscosity was slightly high - virgin VOA is about 10.5. Also slightly surprised that insoluables went from 0.1 to 0.3. The oil filter used was a Mobil 1 M1-209. TBN and TAN look pretty reasonable to me.
I think Iron overall, although normal, is higher than what I typically see on most Toyota engines...I suspect the engine is not 100% broken in yet, I may have jumped the gun on going to a 10K miles UOA interval.
Blackstone commented that "perhaps the oil got hot" - We did not tow anything during this interval, the heaviest load consisted of 4 passengers on a highway trip. During this interval, the truck was used for about 35% highway driving, 65% city/suburban driving.
Comments? My plan is to do another 10K miles interval. The oil was changed and Amsoil signature 5W-30 was used again for the new interval.
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