Since purchasing my Lexus with the 4 cylinder turbo (T24A-FTS) engine, I have wondered if it was a fuel dilutor and if so, how bad. The duel injection (port and direct) is a smart move by Toyota, IMHO, but there is still a direct injector which are prone to diluting the engine oil with fuel.

I finally got my answer with this recent UOA. The results speak for themselves- moderate fuel dilution. Oil used in the test was Pennzoil Ultra Platinum 5W-30; the oil had 4,326 miles on it and the engine had a total of 15,311 miles on it. Mainly city/short trip/cold starts/spirited driving; what I consider to be severe duty.

As for the elevated silicon, I hope and suspect that this due to the gaskets and seals of a relatively young engine. The air filter was changed at around 12,500 miles as I live in a dusty environment. So I don't think that this is due to intake contaminates.

Please use this information as you wish. I have no desire to see this turn into a "which oil to use" or "how often should I change my oil" thread as there are plenty of these out there already. I think that all of us here are capable of making our own decisions on such matters; I simply wanted to share these results.

 

Time to go to 0w40 LOL

I have heard of filters working best when they get loaded up, do you intend run your next uoa with the current filter (I assume its properly sealed) intact to see if that might improve the silicon content in the oil?

 

I won't post this. (Wait, I just did!)




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Ultra Platinum is a good oil, very effective, protective additives. I see that Pennzoil doesn't lie when they promote the Titanium!

What weight does the oil filler cap/owners manual recommend? The 5W-30 is as thick as you need.

Post your next analysis in this topic, would be interested to see if warmer weather reduces fuel dilution by much.

 

I have couple of questions for you and these are not trick questions.

Which parts did you collect for your oil sample, oil from part A or part B?

Do you think the oil in part A is cleaner, the same or dirtier than the oil in part B after 4,326 miles on it ?

Thank you for posting your UOA!

 

Thanks for sharing the data (rather than opinion - a single point of hard data is worth more than a trillion opinions)

I do wonder about the Toyota Genuine oil, which is particularly rich with moly as its additive. Apparently Toyota/Lexus requires the Toyota Genuine oil for only their first oil-change (5K or 10K miles, whichever applies for a particular car), as noted by Lexus technicians on Reddit, and Bobistheoilguy used oil analysis/discussions also point to the bias of Lexus/Toyota corp towards Toyota Genuine oil, due to very high moly content.

Since I won't go to any Lexus/Toyota dealer for oil changes, and will be getting it done at an honest, trusted, independent mechanic who can source and use the Toyota Genuine oil (rather than their Valvoline), I'm trying to decide on the Toyota-genuine.

 

Too late- I just competed the oil and filter change yesterday. I have never heard of a loaded filter working more efficiently; I will have to look into this. Thanks for the idea!

I did the change with the same oil and OEM filter (the last filter was also OEM). This is my last OEM filter in inventory, I will be using Fram Endurance filters moving forward. I plan on continuing my OCI's at 5,000 miles but will probably change out the filter every other oil change (10,000 miles) once I move to the Endurance filters. I will probably wait and do my next UOA in around 10,000 miles. Hopefully by then the Silicon will be down.

 

I meant air filter not oil filter just fyi.

 

I just knew that someone here wouldn't be able to resist such a comment! Thanks for putting a smile on my face!

I agree that PUP is one of the better oils available which is why I use it. I am continuing with it for now as I have a fair bit in my oil inventory. I have no qualms using it for 5,000 miles despite the dilution.

The North American owners manual "recommends" 0W-20 and this is also found on the oil filler cap. But other markets allow for a broader viscosity choice: UK; 0W-20 and 5W-30; Australia; 0W-20, 5W-20, 5W-30 & 10W-30. Yes, the same engine and all of this is easy to find with a simple search. But since I really don't want to go down this rabbit hole on this forum and post, I will end by saying that I am sticking with either a 0W or 5W-30 oil.

To each their own, and as I stated earlier, everyone may use this information as they see fit.

 

Thanks for the clarification! I obviously misunderstood you.

 

I took my sample from A, about midpoint of the oil drain. I really have no idea what the difference might be between point A and B as I am not aware of any tests done between the two. All I know is that the oil used for a UOA is supposed to come from the sump; either by extracting some from the dip stick tube or while draining the sump.

 

I really don't think that you can go wrong with the TGO. I have heard/read nothing but good things about it. As you stated a good dose of Moly. Lots of good oils out there, IMHO.

 

With the 5k interval any oil is fine. If you can get the toyota lube on sale say $5 a quart or less, I'd use it. Anything higher Im taking an off the shelf oil like Pennzoil or Mobil 1 or Valvoline etc.

 

My thinking is an oil filter with a filtration of 20 - 25µ. Anything bigger than 25µ will be trapped in the oil filter and anything smaller than ≤ 20µ will pass through.

In order to have a clear picture of your oil analysis, one must collect an oil sample from the oil filter (part B) because your oil analysis report will not show anything that is bigger than 25µ.

I hope you and any others reading this thread will let me know their thoughts.

Thank you!

 

Oil threads are always controversial. Honda does recommend only changing the oil filter every other oil change, effective running the filter for double the interval of the oil. Not saying that is actually best nor am I saying that causes any harm. It's just a data point from a well-established manufacturer with a reputation for engines that last a long time.

 

Yup heard of Honda recommending changing their OEM filter every other oil change. The Toyota filters and other OE oil filters prioritize things most oil aficionados would be scared to hear about; flow over efficiency/filtration. Years ago Toyota was about 50% at filtration at a given 20-25 uM while aftermarket these days can go high at 98% at 25 uM. In addition it was found oil filters work best at the beginning and very end of life (not ground breaking and wont effect most oil change habits).

https://www.selectsynthetics.com/ima...ciency_900.jpg

On the Air filter claims that was based on Purolator but I would have to double check the source link:

"As air filters load up with dirt the filtering efficiency increases as the flow decreases."