Welcome to the forum!!! Here, you'll find answers to any and all questions pertaining to your coach, your equiptment and much much more. Don't feel like any question is stupid because it's not. That's how we learn. Remember too, some people have off days so ignore any snarky remarks and move on to the next post. That said, you'll always get better answers if you can provide your coach info or if it's something attached to the coach, a model number or other identification to help us identify it. i.e. you've said you have a diesel. While this question pertains to diesels in general, you might want to identify it further. Is it a CAT, (orange) Cummins (Red) Detroit (Blue) etc. Finally, use of the search box at the top of the page will provide you with lots of good information on your coach, your engine, tranny and those irritating things inside your coach.
Now to your question: Most diesel manufacturers do not recommend adding any oil additives. Use a good quality oil such as Rotella and change it per the mfg recommendations. I change mine once a year in February but we are full timers and use the coach often. I'm pushing 100,000 miles. If the coach is going to be sitting for any length of time, I make sure the fuel tank is full to minimize any condensation forming in the tank. Water is the bane of diesel fuel. Know, or learn how to drain the water from the fuel. You should have a water separator on the fuel filter and learn how to use it. Read your manual or ask here. Try to fill your coach at major filling stations. I like FlyingJ even though they are more expensive. They have filters on their pumps, 2" fuel hoses and have a huge turnover of fuel in their tanks. This means less chance of you getting water in your tank from theirs. It also means faster fill ups. The only thing I've ever added to the fuel is Diesel 911 which restores the flow of diesel fuel and removes traces of water to help prevent gelling. I add a bottle every other fill up. The paraffin in diesel fuel begins to gel at 10-15 degrees farenheit but it will begin to crystallize at 32 degrees so 911 helps.
Again, welcome to the forum.....Dennis
We can do more than we think we can, but most do less than we think we doDennis and Debi Fourteen Years Full Timing
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