1 gal. Of gasoline in 28 gal diesel performance increase.

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Cheapstreetduster

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So 2019 ram cummins 2500 diesel .
I put 1gal. Of gasoline in my tank then topped off with 28 gal of diesel. On a long trip that would require multiple fuel fills. I got a 4 mpg increase in milage and truck runs , better.
Start of trip i topped off def. Filled the tank with diesel. ( no gasoline this time as normal) And set out.
I am towing a small car on an open trailer. Its averaging 39* outside
Truck saw 13.4 mpg average with cruise set at 77 mph.
First fuel stop on empty tank, i put 1gal of super gasoline in the fuel tank. Then topped off with diesel (30 gal tank)
The trucks average climbed and climbed this whole jaunt. At the end of the tank my average went up to 16.2 .
Repeated the same ordeal 1gal gas. 28 gal. Fuel on this fill up. The average mpg went to 17.3.
Upon my arrival I disconnected the trailer for one day of short trip driving. Truck is noticeably crisper throttle. With boost the truck pulls a little better.
I am returning soon with trailer but w/o the car.( empty trailer) I will continue to do this on the return trip.
I have seen roughly an additional 120 miles per tank.
 

oe542bob

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Adding the gasoline will more than likely eventually cost you a new fuel system when your HPFP grenades. So save those couple of dollars, you’ll need thousands later.
 

crash68

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So 2019 ram cummins 2500 diesel .
I put 1gal. Of gasoline in my tank then topped off with 28 gal of diesel.
If your truck hasn't had the HPFP recall performed where the CP4.2 based pump is replaced with a CP3 based pump, can guarantee the pump will grenade itself. Diesel fuel spec in the US is just barely enough for the CP4 based pumps, as mentioned above post people add lube to diesel fuel. The CP3 will take more abuse but gasoline isn't supposed to go through it or the injectors. The fuel pressure between the HPFP and injectors goes as high as 30K psi.
Opti-lube sells a great lube for diesel fuel systems even with modern emissions systems, don't use 2-cycle either.
 

Choupique

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cant imagine this is real.

We used to put gas in our tractors sometimes. It was old-school thinking that the gas would clean the injector nozzles being a solvent and would also clean the exhaust ports and turbine wheels from higher exhaust temps. I'm sure all that was true. We also ran used oil in them, kerosene, and all manner of other crap. These were old tractors from the 50's thru the 80's and would almost run on water.

Running anything that compromises lubricity through a high pressure common rail system is absolutely terrible for it. With a CP4 pump, it's imminent failure. Once they spin a plunger it's game over.
 

Wild one

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It used to be a common thing to add a gallon of gas to farm tractors in the winter when i was a kid in the 70's,they'd start alot better at -30. I wouldn't really reconmend it now though
 

JayLeonard

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It used to be a common thing to add a gallon of gas to farm tractors in the winter when i was a kid in the 70's,they'd start alot better at -30. I wouldn't really reconmend it now though
I ran a VW Rabbit diesel pickup for a few years and the owners manual described putting gas into the tank when temperatures were low. From what I remember it was something like 25%. They used a pretty low pressure Bosch VE pump. I never ran gas in though. I never would today either.
 

Wild one

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I ran a VW Rabbit diesel pickup for a few years and the owners manual described putting gas into the tank when temperatures were low. From what I remember it was something like 25%. They used a pretty low pressure Bosch VE pump. I never ran gas in though. I never would today either.
Back then the theory was it kept the diesal from waxing up and gelling,as the gas being a solvent kept the wax from solidifying/gelling.Whether that theory held true,i can't comment on,but i do know the tractors did start better with a gallon or 2 of gas in the tank.
 

turkeybird56

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If your truck hasn't had the HPFP recall performed where the CP4.2 based pump is replaced with a CP3 based pump, can guarantee the pump will grenade itself. Diesel fuel spec in the US is just barely enough for the CP4 based pumps, as mentioned above post people add lube to diesel fuel. The CP3 will take more abuse but gasoline isn't supposed to go through it or the injectors. The fuel pressure between the HPFP and injectors goes as high as 30K psi.
Opti-lube sells a great lube for diesel fuel systems even with modern emissions systems, don't use 2-cycle either.
I always ran Diesel Kleen in MY ED. Either the winter or summer blend, boosting lubricity and a lil cetane boost also. Putting gasoline in diesel, makes me tailfeathers shudder.
 
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turkeybird56

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Back then the theory was it kept the diesal from waxing up and gelling,as the gas being a solvent kept the wax from solidifying/gelling.Whether that theory held true,i can't comment on,but i do know the tractors did start better with a gallon or 2 of gas in the tank.
Maybe on such a low pressure system, but I cannot see doing that on these modern HPFP systems, there is barely enuf lubricity now in the fuel and all the added Bio BS.
 

Wild one

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Maybe on such a low pressure system, but I cannot see doing that on these modern HPFP systems, there is barely enuf lubricity now in the fuel and all the added Bio BS.
The quality of diesal these days,is not the same quality as farm diesal was back in the 60's/70's/80's etc.
I wouldn't throw gas in the stuff they call diesal now that's fer sure
 
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