Let me start by saying I'm not complaining Castrol products are in my engine. I took my 2020 Subaru Forester to the dealership for it's first six month/6000 mi oil & filter change/tire rotation/inspection and noticed on my receipt they used 5 qt. of Castrol 0W-20 for the oil change @ $4.22 a quart. Three months ago I went to the same dealer and requested 5 quarts of engine oil and a filter since I was planning (but didn't follow through) on changing my oil @ 3000 mi. At that time they sold me 0W-20 OEM Subaru Engine oil @ $7.10 a qt.. I guess I'm somewhat chuckling to myself due to what they sold me previously to what they used this oil change. So I guess my Warranty won't be voided when I switch to either Mobil 1/Idemitsu/Pennzoil/Castrol products after I use the OEM Subaru oil I already have on hand. Always learning new dealer protocol and what questions to ask next.