royclem Report post Posted May 9, 2015 I have a 2015 RV with a Cummins/Onan generator does anyone know where the drain plug and oil filter are to change I looked underneath and behind the front cover but can't find either. I have installation guide but no owners manual. Share this post Link to post Share on other sites
wolfe10 Report post Posted May 9, 2015 Roy, Which model Onan do you have? Share this post Link to post Share on other sites
royclem Report post Posted May 9, 2015 Brett it's a 4KYFA26100P 120V 33Amp. Share this post Link to post Share on other sites
huffypuff Report post Posted May 9, 2015 Owners manual here. https://www.cumminsonan.com/www/pdf/manuals/981-0503.pdf YouTube video Share this post Link to post Share on other sites
royclem Report post Posted May 9, 2015 Thanks, I went on Cummins/onan website and found what I need the only problem is it list two different oil viscosity's 15w-40 or SAE30. How do I determine which one I need? No oil filter involved. Got spark plug # and air filter # and found where to drain oil. Any idea which oil would be the best? Share this post Link to post Share on other sites
desertdeals69 Report post Posted May 9, 2015 Both will work fine. When we were an Onan dealer we always used SAE 30. Share this post Link to post Share on other sites
royclem Report post Posted May 9, 2015 Thank you very much Ray that was very helpful saved the links incase I need the info again, But I still don't know what viscosity to use 15w-40 or SAE 30 is it a personal preference or is the climate you drive in, how often you use generator, I Don't Know Share this post Link to post Share on other sites
royclem Report post Posted May 9, 2015 Thank you Desert Deal sounds good to me Share this post Link to post Share on other sites
royclem Report post Posted May 9, 2015 With a lot of help I was able to find the drain plug and change the oil on the generator. Thank you to those who replied. Share this post Link to post Share on other sites
elkhartjim Report post Posted May 9, 2015 I strongly suggest you exercise (run/operate) the generator under at least 50% load one hour per month. I assume your dealer is getting you an Owners Manual since its a 2015 model, if not, Google it, print it out and read it for general information. Share this post Link to post Share on other sites
royclem Report post Posted May 10, 2015 I strongly suggest you exercise (run/operate) the generator under at least 50% load one hour per month. I assume your dealer is getting you an Owners Manual since its a 2015 model, if not, Google it, print it out and read it for general information. Yes we do run it. I also drive it at least once a month for about 60-70 miles. Thank you for the suggestion. Share this post Link to post Share on other sites
huffypuff Report post Posted May 10, 2015 Jim I posted the link to the owners manual so no more needs to be done except to download and save the PDF file. Share this post Link to post Share on other sites
wildebill308 Report post Posted May 11, 2015 Let me stir the pot a little. I recommend the 15-40 as you are cover what ever the conditions are. I also recommend using Mobil 1 full synthetic for the extra protection. Bill Share this post Link to post Share on other sites
kaypsmith Report post Posted May 11, 2015 Since the pot is still simmering, 15-40 for year round should be best. But I would not go full synthetic for a couple of changes, I would use 50 regular, and 50 synthetic the first oil change, 25 regular, 75 synthetic next time around, then full from then on. This gives the engine a chance to acclimate to the generosity of full synthetic. Share this post Link to post Share on other sites
jleamont Report post Posted May 11, 2015 I ran 15W40 in our's when we had the gasser. It was a Microlite 4000 Onan. Seemed like the best fit for all seasons, I had called Onan at that time and they recommended it. Just my two cents . Joe Share this post Link to post Share on other sites