When was it ever a concern?
But even using the same brand oil does not guarantee that you will always have the exact same oil.It might even be preferable to some small extent, as different formulations protect to a minimum standards, but all vary slightly in their detergent and cleaning properties.
But even using the same brand oil does not guarantee that you will always have the exact same oil.
Formulations are always being tweaked, so an API SP oil made today may be different than an SP oil made in 8 months from now when you do your next oil change, even if it is the same brand and weight.
The API standard does say all oils must be compatible with each other, but you always hear those talking about additive clash (which I have never seen any proof of) being a potential problem.
And that is not even considering API changes. Who knows what API SQ or SR will be, besides being compatible with API SP.
I rarely use the same brand and weight oil in my vehicles (although I have just started using my Rotella Gas Truck stash, so some of my vehicles will be getting the same oil for a few changes), and have done quite a few frankenbrews in the past. as well as using different oils as top off oil. I think my F150 has 3-4 different oils in it now (original fill of Pennzoil Platinum 0w-20 (SN), and 1 qt top offs of Supertech 5w-20 conventional SP, Mobil 1 AFE 0w-20 SN, Castrol Magnatec 5w-20 SM, and maybe something else.
I remember that!!! You be getting some weird blend quartThe old metal oil cans that used the piercing nozzle. that can and nozzle always got stuck in the rack to drain into another container. Think of all the people that unknowingly got that quart in their car.
I just bought two jugs of PUP 5w-20 for $19.88 each on Amazon. that price comes with a 25 buck rebate.I buy a whatever premium brand I can get on sale.
Right now it’s Castrol ep. Next will be Mobil 1 ep. Don’t have a fundamental problem with house brands—-I’ve seen too many good UOAs on Supertech synth. If a premium brand weren’t on sale I would go for it.
Used Motorcraft 5w-20 through the extended warranty period. Pre-Covid the changes at Ford Quicklane were on perma-sale. Excellent UOAs and plenty of moxie as long as you kept IOLM to 20%or so.
I just bought two jugs of PUP 5w-20 for $19.88 each on Amazon. that price comes with a 25 buck rebate.
+1There is a good aspect about sticking to one brand and it’s not having to worrying. No chasing rebates or looking for deal. You always know what you’re going to buy, you always buy your brand, and you move on about life. There is a simplicity to it which is nice.
There is a lot to be said about keeping life as simple as possible.+1
I'd be less than truthful if I said that price didn't matter. It does, but to a very small degree. I check the price at three sources and buy the oil at the source that offers the best deal. I look at WalMart, Amazon, and O'Reilly, make my choice, click, and I'm done. If there's a Mobil1 rebate, I'll consider that when making the purchase.