Resistance to shear and viscosity change resistance would make sense to be more important .
How do HPL oils handle fuel dilution issues?
- Thread starter ZZman
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I went with HPL primarily to combat viscosity loss for track use I was seeing with all the brands I'd tired for the Euor 5W40s...some of this drop in viscosity can be attributed to fuel dilution, but some had to be oil shearing to some degree. Enter HPL Euro 5W40 made with Star VIIs. You can search/find my UOA-bonaza post(s) with my data, but since starting to use the HPL product, my viscoity is holding steady, even with track use, in the low-12 CSts vs. 10s-11s before with M1, LM, etc. So for me, HPL DOES help with viscosity loss due to fuel dilution indirectly by having a more consistent viscosity overall to help offset to some degree the inevitable drop from fuel.
BrendanC
$100 site donor 2024
speaking of that, any track days coming up for a new UOA after the silicon debacale?
Memorial Day....mayyyybe a time trial before.
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- Apr 12, 2025
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I drive 6000 miles a month. Overkill pointed out that I have fuel in the oil and Blackstone wasn't showing it. If a guy like me can have fuel in the oil, and in freaking September and March, then most of you folks are in deep trouble. Change your oil regularly. Let the filter stay, just suck the oil out.
SammyChevelleTypeS3
$50 site donor 2023
You can bet there are many thousands of drivers running all over the land who have fuel dilution and do not have a clue even what it is or the fact their cars have it. I freaked when I first learned about it and expected it to be the death and destruction of many autos on the roads but apparently it must not be as big a deal as first thought. I am sure if someone does not keep up with recommended oil changes they will be in for surprise one day. But so far there are no reports of major amounts of vehicles requiring engine overhauls due to it.
I think the best remedy for fuel dilution is more frequent oil changes, with a switch to a higher viscosity oil. Using a top grade oil certainly isn't going to hurt anything. But it won't replace the need for more frequent OCI's
Everything you stated prior to, except this. Problem with a statement like this, any engine failures/rebuilds/overhaul that do exist, difficult to pinpoint to a root cause, such as fuel dilution. Still could be a contributing factor.
That’s where I’m at. I’ll use supposed “better” oil. Torco, HPL ,Schaeffers and HPS but I’m still going to change it before the OLM says to. My wife’s newer car used a little bit of hpl on this last run. Nothing concerning, but out of character for Nissans 2.5. I’ve got torco in it now and will keep an eye on it.
Another thing regarding fuel dilution, is the type of driving you do. Short trips around town in cold weather will obviously require much more frequent OCI's, than long highway trips, that get and keep the oil temperature up to or over 212 F. Which helps evaporate the fuel out of the crankcase.
My short tripper/Minnesota winters Hyundai had some very very bad fuel dilution and I was monitoring it at Polaris Labs. I got as high as 1.5qts in a "4 liter speced world car" in a 3,000 mile oil change regiment. This was also on a tuner car that was thrash daily. All my oils where high end and boutique oils. At last trailing end of this issue I was running exclusively Mobil1 5W-30 ESP for 1.5 to 2 years. I also used Amsoil SS, Mobil 1 Extended. At 1,500 miles I would pump out oil to lower my level, and it come right back slowing gaining oil quantity. I always test out in the "ok" spectrum for wear for my engine. I later learned to not worry about it and it became common place. I knew about this issue before I bought my car as I had the 10 pack of pre paid oil sample bottles through my oil sampler that used Polaris Labs exclusively. I had the 10 pack of sample bottle before I took possession of my car.
It took Redline Performance 5W-30 Euro to finally loosen up my, what I think were my top jammed rings allowing fuel to get into the crankcase directly. I have never lost oil quantity in this car. I then switch over to Motul 5W-40 8100-Clean Gen 2 ( summer oil) and used HPL EC every other change to keep it at bay. I also ran VR&P 5W-30 this winter for FIVE oil changes (3,000 mile dumps) to make sure I got all the carbon I could get freed from my ring lands. Fuel dilution at least on my car had to do some damage, but even at my over the top high levels there was not excessive wear to worry about.
It took Redline Performance 5W-30 Euro to finally loosen up my, what I think were my top jammed rings allowing fuel to get into the crankcase directly. I have never lost oil quantity in this car. I then switch over to Motul 5W-40 8100-Clean Gen 2 ( summer oil) and used HPL EC every other change to keep it at bay. I also ran VR&P 5W-30 this winter for FIVE oil changes (3,000 mile dumps) to make sure I got all the carbon I could get freed from my ring lands. Fuel dilution at least on my car had to do some damage, but even at my over the top high levels there was not excessive wear to worry about.
