It won't cause permanent damage to the engine than carbon buildup, but it might damage the in-tank fuel pump, clog the catalyst, and ruin the oxygen sensor. But first, I will assume that what happened was that, by mistake, the car was filled with diesel in the tank at a gas station. Then, I will assume that there was still some gasoline left in the tank. That said, what will happen is that the remaining gasoline will mix with the recently-pumped diesel, will lower significantly the octane rate of the fuel available, causing a lot of noise, in the form of knocking and pinging to the engine, and the engine management system might shut it down eventually. So, if the amount of diesel was greater than the amount of gasoline, the engine will stop running very soon. On the other hand, If the the amount of gasoline was greater than the amount of diesel, the engine might be able to continue running, causing damage to the components mentioned above, and still making a lot of noise. The solution will be draining all the contaminated fuel from the tank and replace it with the highest octane fuel available, and take all the contaminated fuel from the system by blowing compressed air, from the front of car, on the engine side, to the tank, with the pipes disconnected from the tank.
Then, you need to pay close attention to future the check engine light indications, adverse fuel economy and/or unusual smell of the exhaust. Damaged catalyst and sensors might not require immediate replacement, but will fail in the near future
Diesel fuel injector cleaner will not hurt your unleaded gas motor. The diesel fuel injector cleaner is basically the same as your unleaded injector cleaner.
.Mixing a small amount of oil in the diesel fuel will not hurt a motor. The motor will run rough and produce black smoke.
Yes, ESPECIALLY in a newer truck designed to run on Ultra Low Sulphur Diesel, and especially if it had a Diesel Particulate Filter.
run what is recommended. but higher sulfur will not hurt it at all current diesel fuel is 50ppm
no, a small amount of gas will not hurt a diesel motor. in fact ,before all the diesel supplements were available, truckers would use some gas in their fuel in the winter to remove moisture,and to stop the fuel gelling. also used sometimes to boost power a little. gasoline also cleans injectors
Some diesel fuel is only supposed to be used by farmers. It is cheaper. The dye is there so it can be found if used in improper vehicles. The fuel is the same, just dyed. It will not hurt to use it.
The Navistar 6.0 is junk to begin with, so I wouldn't be too worried about that. As for off-road fuel, it won't hurt the engine, per se, as the 6.0 was manufactured prior to EPA2010 regs, but it is illegal to use red dye diesel in on-highway applications.
If you filled it with more than a couple of gallons, you will need to drain the fuel tank and fill it up with unleaded fuel. It will not hurt the engine to run it with the little diesel left in the tank. You may also have the drain all the fuel lines to get it started. I would also replace the fuel filter.
If your car is not a Diesel, YES! It will harm your car. Diesel fuel is less refined than conventional gas. It has contaminants and water in it. You may end up with carburetor problems, and if you have fuel injecion you may have a very costly fuel injector repair on your hands. Please only use the fuel recommended for your car. Most cars nowadays have that printed on the inside of the gas tank door where the cap is.
YES
NO
Depends how much, If it is less than 20% of the total fuel capacity then fill it up with gas and run it. It will smoke quite a bit but should be OK. Diesel has more lubricity than gas which should not hurt the fuel system. You might want to syphon out the diesel mixture best you can if it won't run any good. Running it should not hurt the injectors or to much just don't work the engine to hard as it may operate at a higher temperature. If it does run hotter then stop and you will have to clean out the diesel somehow. Running it to hot could result in engine damage.