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

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Stavinksi

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A few years ago we spent a couple weeks in Switzerland. I had reserved a "midsize" sedan but when we got to the counter there were none available. We could either go with a Compact, or a Mercedes. We upgraded to the S-Class MB. Lovely car. Quiet and refined. Filled it with Premium 3-4 times before returning it.

After we got home I was researching that specific model for the Swiss market and found they only made them in Diesel... Kept expecting to get a call/email from the rental company telling me I had killed it and they wanted $20k to fix it...
Yeah yeah but did the fuel economy improve?
 

Choupique

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would always add kerosene to his tractor diesel tank during the winter

#1 diesel fuel (winter fuel) is for all in tents and porpoises kerosene.

Most of you guys up north and out west are basically running straight kerosene in the winter.
 

Dean2

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#1 diesel fuel (winter fuel) is for all in tents and porpoises kerosene.

Most of you guys up north and out west are basically running straight kerosene in the winter.
Yes, and thus the need to run lube in it. Jet fuel is also kerosene but burned in an entirely different way.
 

GTyankee

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Back in the mid 1960s, I use to visit friends on a Southern California Indian Reservation.
I was still in the Navy when i met them.
THe woman was in charge of the Tribes Finances.
When i needed to go back to North Island, where my Carrier was docked.

That woman would let me top off my gas tank with AV Gas & my 1956 Ford ran real well on that stuff

I think mine had a 272 Cu. In in it when it left the factory
One year when i went on a WEST PAC, i sent the engine to a machine shop for a rebuild & better camshaft, i had the Automatic Transmission reworked to take the power of the engine
 
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Goose55

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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.

If it's just one gallon of gasoline to 29 gallons of diesel that shouldn't create a problem. But don't go beyond that.
 

nlambert182

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If it's just one gallon of gasoline to 29 gallons of diesel that shouldn't create a problem. But don't go beyond that.
It will..... do NOT do this. Ever. Under any circumstance.. but especially under warranty.

Gas is a solvent. It will reduce the lubricity of the diesel and eventually cause not only the HPFP to fail, but also the injectors. It's quite literally the quickest way to kill the engine.

IF a customer was under warranty and anything on the fuel system failed the first thing Cummins had us do was test the fuel. If any trace of gasoline was found, the warranty was void on the spot. That's a $10k+ repair bill for the customer. Navistar/International was the same way. Oh.... your 6.0 or 6.4 popped head gaskets? Test the fuel. Gas in the fuel? Warranty void. Every single time.
 

M376X6

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Bought, repaired, and restored well over forty M35 and A2 deuces over the years and then would sell them. The old multifuel engines were pretty decent engines. They added a turbo to improve the emissions. Later a mod was created to bypass and effectively disable the compensator which meant the truck could only burn #2 diesel from then on. Did a few deuces with the old OA331 gasoline engines. Had a lot of fun in my shop over the years. I paid a little over a hundred grand for my latest Ram, I don't think I'll try screwing around with adding gasoline or any other fuel to it. I will use an additive that cuts down on jelling but only if it states it won't hurt the high output Cummins.
 

Doug Ram

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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.

This is a prank right?
 

Docwagon1776

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If it's just one gallon of gasoline to 29 gallons of diesel that shouldn't create a problem. But don't go beyond that.

Show your math. What's the new flash point and what's the lubricity? What's the dealer requirement for warranty work? What's the OEM state about it? You're the guy that was scared to hold down buttons to reset his radio but you're going to advice people to use non-recommended fuels?

I'd hate for anyone to think you knew what you were talking about and damage their vehicle.
 
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Summit1

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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.
So 2023 Ram Cummins 3500 diesel .

I bought this truck (as well as most of my previous vehicles during the past ~20 years) new because if Faecesbook stuff such as this.
 

David James

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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.
I've owned and driven diesel vehicles and equipment for well over 40 years. I'm no tech expert, but have been to a Holiday Inn Express. Just my opinion, but you are setting yourself up for disaster and thousands of $ worth of repairs to fix what ain't broke - yet. It will be. If your remedy was recommended, it would be in the OEM specs. Years ago there were emergency anti-gel solutions used in extreme cold conditions that included using a minimal amount of gasoline to penetrate jelled diesel. The caveat was that specified treated diesel fuel should immediately be added once the engine was started and cycled through. Gasoline is NOT a diesel fuel additive. Get Power Service, Motorkote, or any number of approved products designed to benefit the fuel and the delivery system. Frankly, anyone with a diesel prime mover shouldn't need to be reminded of the need to use a top quality fuel and approved additives on a regular basis. Jackwagon solutions such as these are proof that a fool and his money will soon be parted.
 

farout75

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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.
You would be MUCH better adding Kerosene than gasoline. Your experiment may well be slanted by tempt. wind and other factors.
 

TestPilot57

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Putting aside the fact that adding gasoline to diesel is a terrible idea in a modern engine, what is the logic that doing so would increase mileage? As pointed out in at least one previous post, gasoline has energy (BTUs) per gallon than diesel. Whenever someone tells me I can get more from less through some sort of magic, I am immediately suspicious.

By the way, where is the OP on all these statements/questions? Broke down in the hinterland where no cell service exists?
 

Randy Grant

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Bought, repaired, and restored well over forty M35 and A2 deuces over the years and then would sell them. The old multifuel engines were pretty decent engines. They added a turbo to improve the emissions. Later a mod was created to bypass and effectively disable the compensator which meant the truck could only burn #2 diesel from then on. Did a few deuces with the old OA331 gasoline engines. Had a lot of fun in my shop over the years. I paid a little over a hundred grand for my latest Ram, I don't think I'll try screwing around with adding gasoline or any other fuel to it. I will use an additive that cuts down on jelling but only if it states it won't hurt the high output Cummins.
That was before ULSD, and loss of lubricity.
 

GaryDB

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Wait... what about 5gal of non-ethanol gas and ...a Quart of Mobil 1 or should it be 100% synthetic...or maybe green top Quaker State..no, no red top...... oh, and add a can of STP.
 

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