Oil and gas vs fuel dilution

Mar 15, 2012
PEARL River la
Sorry for the long post but It is as short as I can get it

I haven't seen this discussion but with all the new technology out there on our vehicle I think with all your opinions it just might help someone make a decision. We will start off with my Van. Simple design with port injection and VVT. We all can agree that GDI is a fuel dilution nightmare so please inject it into discussion. I have run enough with my vehicle to know that in town running oil gets dirty early and when drained it flows quickly so I suspect fuel leakage from rings into oil (not enough to raise level)
Conventional oil and Synthetic oil gets many opinions about which one based on price as well as fuel. Conventional is slightly thicker and according to popular opinion holds contaminates longer and Synthetic dissolves it. Synthetic last longer to accommodate the higher price,(not counting sales and rebates). Cars today are built with less maintenance and lower cost of ownership and this is the problem. Oil squirters cool pistons so it will eliminate ping but downside is fuel has to be at optimum temp for correctly burning. What used to be a hot burn would melt a hole in piston when using lower octane now pushes fuel past rings so emissions are less as well as less fuel. Problem arises from carbon is cleaned by going to oil instead of exhaust and intake valves aren't cleaned by fuel. The best way to combat the problems is run a good oil and and good fuel. Everyone wants fuel mileage so this is where we are. I was reading Exxon page where they explained why Super is not just Octane any more. They put a lubricant in to combat lubricant loss from fuel dilution with extra protection from carbon buildup. I read lots of sights claim a waste of money to run higher octane although your engine runs cleaner and more efficient on the better gas. Now let's put this together. 2018 Grand Caravan running regular and conventional oil at 10k (according to the manual) OCI no econ mode 17 city 25 hwy. Turn on ECON then you get 18 city 25 hwy
Change to Synthetic without ECON 17.5 city and 25 hwy
Change to Synthetic with Econ 18 city 25 hwy
Midgrade netted another mpg
I don't have enough data on Synergy Supreme yet but can say smoother all the way around.
As you see if Super continues the trend then I will gain 3 mpg in town driving with more protection from shear with fuel dilution if you believe their claim
If my Van had more miles then a slow increase in fuel mileage would take longer cause of carbon buildup
Now is it worth it that up to you. I don't buy fuel grade for fuel mileage and I do 1000 mile tested on everyday driving seeing which one keeps pipe cleaner , less noise from injector, as well as how well it runs. Louisiana temps are high with higher humidity so AC gets run almost all year
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I ran Top tier in last vehicle which carbon up. I did the seafoam etc. but ultimately only fix was tear down so I experimented with higher octane which was midgrade. Fuel mileage was not great but I traded it in.
Paragraphs would have been a big help.
Hard to follow but a couple comments on the title …
DI dilution in 0w20 is my main concern … others are PI or spec’d with 5w30. Have been using cheap filters to get a fresh quart in … but will soon install a Fumoto valve to spike used oil.
As for name brand fuels … UCL are not typically oil … and can exploit the fuel dilution path …