Trynforpar Report post Posted October 23, 2015 I own a 2016 Winnebago powered by a Cummins diesel with 3,000 miles. I am about to store the unit for the winter and wondering if I should change the oil with only 3,000 miles on the engine. What does everyone recommend. Share this post Link to post Share on other sites
wolfe10 Report post Posted October 23, 2015 There are two aspects to the answer: 1. What would keep your maintenance history within the guidelines of Cummins so you engine warranty is unquestionable? 2. Is the oil in the crankcase still in good enough shape that it will not negatively impact engine life? I will let #1 up to you/your owners manual. #2 is a bit dicey. On the surface, 3,000 miles in a clean-burning diesel is very low miles. BUT (yes, a big but) there was undoubtedly a LOT of idle time, with the engine turned off before reaching operating temperature. This did leave moisture in the crankcase. The engine was installed in the chassis. It was then driven from the assembly line to a storage lot. No idea how long it was there (you can find out chassis build date from the chassis manufacturer). It was then started and driven onto a truck or RR car for transport to Iowa. It was then started and driven off the truck or RR car and stored for some period of time at Winnebago. It was then started and driven to the coach assembly line. It was then started and driven from the assembly line to a storage lot. It remained there for some period of time. It was then driven to the dealership. At that point, it may have been driven on multiple short test drives and/or many dealers start the coaches and run them in place to keep the batteries charged. A diesel is too efficient at idle, even fast idle speed to get the oil warm enough to rid itself of the moisture that is a normal byproduct of combustion You then bought the coach. From there you do know the history of how the engine and oil were treated. In short, I am sure you will get advice that says do nothing. But, were it me, I would change it, based on both #1 and #2. Share this post Link to post Share on other sites
elkhartjim Report post Posted October 23, 2015 I would change based on number two and then you don't need to worry about number one. Good example, Brett. Share this post Link to post Share on other sites
jleamont Report post Posted October 23, 2015 So, lets add to the question, do you change it before it's stored for the season or in the spring before your first trip? I always take it for a ride in the spring, get it warmed up and service the coach for the season, immediately upon return while its hot, is this the correct process? Share this post Link to post Share on other sites
wolfe10 Report post Posted October 23, 2015 So, lets add to the question, do you change it before it's stored for the season or in the spring before your first trip? I always take it for a ride in the spring, get it warmed up and service the coach for the season, immediately upon return while its hot, is this the correct process? A question that has been long debated! Here is what I have done historically with diesel engines and why: If oil is over a few thousand miles old and the coach is going to be stored, I change the oil. Acids form in the oil and I don't want them sitting in the engine all winter. Yes, this was a significantly more serious problem with the higher sulfur content diesel which when the sulfur byproducts of combustion came into contact with moisture in the crankcase turned into sulfuric acid. OK, so the new ULSD fuel is less problematic. So the reasoning for changing before storing is not so overwhelming. Reality-- I think either route will result in an engine that will well outlast the rest of the coach with reasonable maintenance, no overheating, etc. Share this post Link to post Share on other sites
jleamont Report post Posted October 23, 2015 Brett, as I was typing it I was out weighing the pros and cons either way. I figured changing it in the spring was probably the best route since I can assume there will be moisture collecting from sitting in the winter that could potentially be riding along all season unless it’s dumped ASAP, this is when I also pull an oil sample. Up here in the North East I will not move the coach or start it until all of the road salt and brine has been washed away by late winter/early spring rain so I can complete a through warm up cycle. The stuff that gets put on the roads up here makes sulfuric acid look like something you would consider placing on your pancakes in the morning. Thanks again Share this post Link to post Share on other sites
wildebill308 Report post Posted October 24, 2015 I own a 2016 Winnebago powered by a Cummins diesel with 3,000 miles. I am about to store the unit for the winter and wondering if I should change the oil with only 3,000 miles on the engine. What does everyone recommend. Well just as you have been advised, you should change your oil to keep your warranty in place. After you are out of warranty you can change it when ever you want. I still maintain changing it in the fall is the best practice. I would much rather have new oil with a complete additive package rather than letting it set with older more contaminated oil. Remember if you should get moister it will possibly cause more damage with the older oil. I also pull the oil sample far enough before your oil change you can get the results back. This way if you have a large change in your results you can do a second sample to verify the results. Bill Share this post Link to post Share on other sites
five Report post Posted October 24, 2015 I own a 2016 Winnebago powered by a Cummins diesel with 3,000 miles. I am about to store the unit for the winter and wondering if I should change the oil with only 3,000 miles on the engine. What does everyone recommend. The easy answer is to do what the manual says. My previous coach had an ISL and said change the oil at 20k or one year, whichever came first. My Detroit Diesel in this coach says 35k...no time limit. Share this post Link to post Share on other sites
bm02tj Report post Posted October 25, 2015 Oil oxidizes, so if in doubt change it. It is cheaper to change than risk it. Share this post Link to post Share on other sites