Forum Discussion
RambleOnNW
Mar 04, 2014Explorer II
Ran conventional oil up to about 28 hrs, then switched to Mobil 1 10W-40 High Mileage Synthetic. I run this due to its higher level of ZDDP, the zinc/phosphorus anti-wear compound. The manual for our Onan specifies SL oil, and the Mobil 1 HM is an SL (as well as SN) rated oil. Compared to the conventional 15W-40 the Onan seems to runs smoother, and when shutting it off it doesn't have as dramatic a "chug-chug" as it used to while stopping.
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