10k oil changes ! Lol your bearings hate you and so does the next owner.. an oil change is a small price to pay.. I’ve torn down many of engines because of 10k mile oil changes…

And your point is??

Where did you get it done that cheap?

should have gone to Sumter Tire

I don't believe the OP said that regular & synthetic oil were used.

I’ve never heard of this ratio. If you are putting in synthetic oil, all oil, not so many ounces are synthetic.
I’m guessing they added some additive to the oil and that additive comes in a small bottle

And yet... for newer vehicles 10K or 365 days is the recommendation. I followed that recommendation for my previous vehicles which I traded in at 160K-200K miles. (16-20 oil changes).

Yes
 

The cars I’ve had recently were spec’d with fractional quarts for oil changes - I always get billed for full quarts (e.g., 7.4 and pay for 8). No big deal.

I know ppl who change their own oil and avoid this issue.

The fraction may have to do with liters and quarts being a little different.

You didn’t mention the make, model and engine size of your vehicle. The reason I ask is because depending on the oil filter location on the engine, the fluid capacity of the oil filter needs to be added to the crankcase capacity.

Overall, as another person suggested, unless you requested a very specific type or viscosity motor oil, most dealerships use bulk oil (55 gal. Drum or Bulk Tank) hence their cost of good is significantly less than selling by the bottle. I suspect that this dealership (stealership) is overcharging customers by claiming they used bottled oil when in fact they used a (same quality) but lower cost product.

If you have concerns, I’d suggest going back and having a face to face conversation with the Service Manager.

I’d also suggest checking your oil to ensure that your crankcase is not overfilled. With newer engines, overfilling can result in the crankshaft coming in direct contact with the oil which can cause frothing and create engine issues.

Oil capacities are typically labelled in the owner's manuals as "with filter change", or some similar language.

The trouble with letting others change your oil is that you really don't know what they are putting in your car, they may not even change your oil filter, how would most people know ?

Next time ask for the partial qt bottle back since you paid for it (at an inflated price)
I would just got to a quick change oil place and not to the dealership if it was just for an oil change. Save a lot of money.

They don’t use bottles. Have you never seen how they change and refill your oil?

Sometimes, I will pull out the dipstick to see if the oil looks new and that the level is correct.

Just be glad you don’t have to pay big bucks for a Mercedes oil change.