[Periokid]

So I got my car back and the service invoice states that the dealer changed the oil and filter and the pollen filter. There is no mention of the differential oil being changed on the invoice. My car has DCT so no transmission oil change as expected.

I called the dealer and at first they said I do not need that service because I have the DCT but I questioned that and they said they changed the differential fluid.

Now, I don't know if they changed it or not. There is no record or documentation that says they did. I examined the differential in my garage and the differential drain and fill plugs seem untouched and there is no evidence of oil drips or marks (unlike the engine that had oil all over).

So what do I do? Suppose it was changed but I have no record of it? Would this effect future warranty if there is a failure? Effect resale?

Or worse, suppose it wasn't changed? Is this a recipe for differential failure?