For 4 cycle oil the branded OPE oil prices are expensive. John Deere 5W-30 SN, GF5 oil is $5.98/quart, at Lowe's. Nothing on the bottle about it being synthetic or a synthetic blend. Briggs and Stratton 5W-30 oil is $4.98 for 18 oz
. It has no API rating, only "warranty certified". Briggs and Stratton 5W-30 synthetic oil is now $9.98/quart at Lowe's
. Walmart across the street has Mobil 1 HM 5W-30 for around $22/5 quart jug! This is API rated SL, supposedly better for air cooled 4 cycle engines than the more current API SN rated oils.
Whimsey
Whimsey