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DAS26miles's avatar
DAS26miles
Explorer II
Jul 01, 2018

Onan 4K needs oil change, which oil brand and SAE

My Onan 4K is about to need the 150 hour oil change. Last service was thru an authorized service dealer and I know it was expensive. I used to use Pennzoil 30 in my Winnebago as I don't travel where...
IB853347201's avatar
IB853347201
Nomad II
Jul 02, 2018
As recommended by Onan, we have always used 15W40. Understand its a must in regions where the temps vary especially into the highs of 100 degrees.

Have used various brands, doesn't seem to be an issue as long as a premium brand name.

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