UOA Pennzoil Ultra Platinum 5w30 - 2zrfe

[tmontague]

Above is my most recent UOA for Pennzoil Ultra Platinum 5w30. The oil was in the car for just over 13k km. Of those km's about 800-900km were of very heavy track driving. They were 35-45 min sessions with a lot of WOT and high rpm's. The oil peaked at 290F and typically was in the range of 265-290F while at the track. The DDing was a mix of about 60/40 highway and city.

The most recent UOA is the one on the far left. The 3 on the right are with Mobil1 0w30. The two right most ones are with the 1nz and the 2 left most are the 2zr - very similar results. As you can see I originally started out testing the Mobil1 by pushing it to longer OCI's to see what it could tolerate. I then switched to Pennzoil UP due to hotter temps at the track and tested that sample out.

I was running Toyota OEM filters and they were changed at 8k km and oil added as needed to replace what was lost. I wanted to use the same oil for a whole season for a few reasons. I have always heard that you need to change your oil after every track session or at least change more frequently if you are tracking your car. I have also heard that you must use an oil cooler if your oil temps go above 250-260F.

Being an empiricist, I looked into a lot of the oil science and realized that many of those claims didn't seem to hold much weight in the scientific and real world testing. Seeing as I don't have an oil sponsor, saving some cash on $40 oil isn't a bad idea. Turns out the studies are correct. 290F is very much so fine for a top tier off the shelf oil (although I should be running a much higher viscocity). The oil did not degrade, prematurely break down or become contaminated. It still has quite a bit of life left in it. it did look pretty dark when I drained it, but clearly that is a non issue. I actually noticed that this oil got darker a bit faster that my previous Mobil1 samples. I don't know if that is due to the different oil, or if the track time had something to do with it.

UOA's are not the be all end all, but it is a very good objective indication of how your oil has held up throughout its use. It will also shed light on any potential wear in your engine.

What this means for me going forward into next season:

Well for one, I will not be running anymore UOA's on off the shelf top tier oils - it isn't cheap and i have enough data to move along with. Not unless I make a drastic change to the engine ie: head work to increase rpm, or higher compression pistons.

I will be changing to a 40wt oil next summer. Ideally based on my oil temps, I should be running a 50 and even 60wt oil in the dead middle of summer. Problem is, I also dd my car so a 50 and 60wt is too thick for that. I will stick with a robust 5w40 Euro spec instead of a 0w40 which will help not to be too heavy for DDing but more robust for the hot track temps.

I don't think I will be buying any boutique oils for this engine. I think they have their place and are a good product but based on my data, I just don't see the reason to need to spend a ton more $. I think it is the point of diminishing returns with those oils for this stock internal engine on a stock tune.

The 2zr seems to be just as robust as the 1nz, very easy on wear and handles extreme stress very well. The engine was by no means designed to be run at close to redline and WOT for 45 mins with 230F coolant temps and 290F oil temps. However, it handled it very well and continues to do well.