Costco Gas (Oxnard) - has diesel on every 24 of their pumps, Simi Valley only has them on a few pumps / lanes.
Turn on your gaps app. Google: Costco diesel. It should give you the nearest one.
Now at Oxnard and Santa Maria
Costco Simi Valley has diesel.
Costco in Simi Valley and in Oxnard carry diesel but only at certain pumps, not at every pump.
None that I have been to.
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