[keonigt]

I bought my car June 2015. I changed my oil at my friends house at 2700 miles on October 2015. I lost the receipt to the oil that i bought but i still have the extra 1 quart oil bottle and the subaru filter box.

Would the dealer ever ask me for evidence for oil changes?

And Is this sufficient evidence to give if the dealer ask for evidence of oil change?

Any suggestions on how to obtain evidence if i already did the oil change?

Also, do I change oil every 3000 miles or every 3 months?

Thanks!