Mix up all my leftovers for my next oil change

Aug 21, 2012
South Carolina
My dads farm truck (old Ford) gets left over half courts of whatever he is using for the normal vehicles. Once he gets 6 quarts, they go into the old truck. God only knows what that truck has gotten over the years, but it gets a fresh oil change once a year with the mystery brew. He usually uses Pennzoil, but has been using Supertech as of late.

No idea how many miles on the truck, but probably 10 million.
Apr 23, 2021
Use it! How does the sum of the contents at up to less?
My next oil change I do will be a similar concoction. Every oil change I do takes about 4.5 quarts. I always have a pint left over. Got a 5 qt jug full of leftovers now, or at least enough for a 4.5 at oil change.
It's all OW-20 oil but a mix Mobil 1AFE, Castrol Edge, Pennzoil Platinum, and Valvoline. Basically I buy whatever is on rollback or best deal at Walmart.
Cant beat price of the $3.97 MC FL-910s spec filter for my needs.

I'll argue why keep using the same oil? Every oil makers has oil that may have an advantage over1 or another brand. Some oil may claim to be cleaner. Keep pistons cleaner. Some oil may be better with zinc additives. Some oil may be better for oil seal additives.ots how they market the product. Use different oils at different changes. Get the best well rounded protection.