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Gas in diesel

Just put 15 gallons of gas in 35 gallon diesel tank and had to drive about 100 miles because truck was loaded with hay.
Next step: drain; next step: pray?

You put 15 gallons of gasoline in a 35 gallon diesel tank and it still runs after 100 miles? You must be awful lucky. I would drain it all and change all the filters ASAP.

We’ve been discussing engine efficiency over on another thread, and by coincidence, blending gas with diesel with gas can actually improve efficiency if the engine is designed for it:

However, your engine is not designed for it and you are lucky it didn’t melt a piston. Apparently old VW/Audi diesels could run 10% gas in winter, though:

. I assume you had 20 gallons of diesel ? . Best of luck ! The fact that it continued to run works in your favor. But, drain and refill with diesel immediately . I don’t understand. "I had to drive about 100 miles because the truck was loaded with hay? " was the hay more valuable then a new motor ?

I thought hay was only running about $175 a ton. Whatever. Back in the 80’s my dad worked at the Caddy/Olds dealer part time after retirement. They had more than one brand new diesel Caddy or Olds with significant engine damage after the driver put gas in. I think the rule was under 25 miles before the cars stopped dead.

Drain all the fuel out.

Refill with clean diesel

Then stand back and see if the ethanol in the gas had any effect on the diesel fuel injectors


Did the engine operate normally during that 100 mile trip?? I’m surprised you made it that distance…

Engine did knock somewhat. We didn’t have much of an alternative to driving from where we were. All comments are appreciated, though I can’t be made to feel much stupider than I already do!

We’ve all done boneheaded things. It was just your turn. :wink:

Time will tell…

Gasoline is a poor lubricant for the injector pump. I wouldn’t worry about the pistons.

I happen to know of an Army General in transportation that did the same thing to a rental so it happens.

Well, I may have been luckier than I deserve. The tank and filters are drained and flushed, and the truck seems at present to be running smoothly. The mechanic said that, had it been a 6.0 engine instead of a 7.3, pistons would have melted. “Time will tell,” to be sure, but it’s a huge relief right now.

Sounds lke you dodged one. Good job and good luck.

I was in Grand Junction Colorado, just pulled off to get gas when I saw a large rental truck with a power liftgate at the nent pump. A truck that I knew had a diesel. And he wasn’t at a diesel pump.
He was on the phone with the rental company and was telling them he just filled it up and it quit.

I told my wife we had to get out of there, I didn’t want to be watching when he found out what he did.

I’ve driven the truck for a couple of days now, and it all seems OK. There was a bit of a hot smell once after stopping, but nothing really bad and, as I said, it seems to be running fine. The question: I know luck does not trump the laws of physics, so should I expect something to show up in the near-, medium-, or distant future? Or am I just paranoid?

Just a question. Did you do this intentionally or by mistake ?

Chances are any damage to be worried about would have made itself known by now.