You buy three 5 lt. Mobil 1 0-40W from Walmart = 3 x $22 = ~$75 with tax.
Oil filter is about $8-10 from online stores. Get two of those with some other stuff that you probably need to qualify for free shipping.

Total cost for two oil changes = ~$95, still not $40 but less than $50 for one oil change.

Gotcha, thanks. I haven't set foot in or near a Walmart in over a decade. Hence my shock.

Same price on Amazon. Sometimes even cheaper. They deliver to your door in two days for free if you have Amazon prime.

I got a warning to add 1 qt of oil. I added Castrol synthetic 5w-30