Direct injection fuel mixture

[2016sierradi5.3]

I have 2016 sierra 5.3l with cylinder deactivation, I live in Ontario and during the summer months was able to achieve 11.5-12.3l/100km. On my daily commute I average 90km/h it runs about 1200rpm in 4cyl mode. There's two concerns first is now that the cooler temperatures are here I'm lucky to get 14.5l/100k , the truck runs colder and takes longer to heat up, I'm sure this is inheritent due to being direct injected and aluminum construction and the low rpms. It will not run 4cyl mode with the same load under colder temperatures. I can simply try to run a winter front to get to the under hood temps up but here's my second concern our awesome liberal government decided to invoke a carbon tax at the beginning of the year which has taxed our fuel about 4.5cents per litre. My thoughts were to run a mixtures of diesel with gasoline and eventually bio diesel. I've done a little reasearch and the idea seems plausible, with the direct injection my rail pressure is 1400psi similar to the older diesels, the engines compression ratio is 11:1 , I realize I do not own a diesel but hoping to improve fuel combustion characteristics and stored energy in the fuel. These are just some thoughts, I have considered an alcohol alternative but the temperatures in the winter are too cold to be reliable. What are some thoughts.

[Frank Lee]

The higher fuel tax is awesome. Anyone who commutes- presumably solo and empty- in a full-size pickup can afford it. But yours does get really good mpg.

Run a grille block and an engine blanket. Preheat for 1 to 2 hours with a core plug heater. Do NOT idle. Everything runs colder in the cold, not just aluminum blocked engines with DI. Ethanol is harder starting in conventional engines from cold, but cold weather operations are just fine when the engine is warm. I would think a DI engine with 11:1 CR would have fewer if any issues with ethanol on cold start, but I've not personally tried it or researched it.

[oil pan 4]

The problem with diesel fuel is it's refined to ignite as fast as possible on contact with air heated from compression.
Just because diesels are high compression and you engine are higher compression doesn't mean it will work.
Diesels get away with running high compression and unstable fuel by not injecting fuel until after the air has been compressed.
Gasoline engines mix the air and fuel together before or during compression. Gasoline and air have to remain stable during compression and during ignition by the spark plug.
You may be able to run some diesel but don't expect to be able to run more than 20%.

[Stubby79]

Kiss your warranty goodbye if you start screwing with things like this.

[roosterk0031]

Do they give credit for using more ethanol?

I've never had a cold start issue with the 02 Suburban or 10 Impala, but they were parked inside overnight. Now that the Impala is at college with my daughter I'm a little more nervous for running E70 so having her alternate half tanks or run E15/30.

[ThermionicScott]

Well, hey, gas is cheap in my country, so you could always consider moving south of the border.

I can't advise on the mixed-fuel idea, but grille-blocking, a block heater, and an MPG gauge of some kind will make a bigger difference than you'd expect from their simplicity, especially in the winter.

[Hersbird]

I wouldn't mix fuel, besides isn't the diesel more expensive with a higher tax? It is here. Part of the cold weather drop, and it's really cold here, is the air is really dense making your already poor aerodynamics and large frontal aera a bigger penalty. Your best defense is to just slow down and your mileage will come right back. Most likely poor road conditions call for slowing down anyway.
I have cylinder deactivation on my 2008 Hemi and wish there was a tune to "lock" it in. It seems to deactivate at the slightest increase in throttle. Why not be able to hold it until say 80% throttle is applied which would put the motor in a better BSFC anyway. The general public doesn't like that delay and the common custom tune actually disables the deactivation alltogther to make it sound better. Silly people. Maybe GM trucks being more popular and plentiful with the deactivation we will see a tune that is more for economy (real economy, and not just a claimed added benifit of and extra 30 hp and higher shift points).

[bandit86]

Experiment. 1 liter diesel to a 75 liter tank makes high octane gas. Run5, or more. When you start to see white smoke, back off. 10 percent should not be a problem. I have run 10 percent gasoline in my common rail diesel dodge in the summer. I can do more in winter. It runs really good on a 10 percent oil and 5 percent gasoline concoction. I need to play. With timing, it is fully advanced, I could probably run better with lower timing and more gasoline.

[Ecky]

Diesel is low octane, so mixing it in any significant quantity risks detonation. I would advise against it.

[bandit86]

Read the MSDS on 104 octane booster. 99percent kerosene.