Different sound after oil change
 

Hello guys, first post, be kind :)
Short story:
I took my 2008 Lancer GTS for an oil change and after that its making a different sound whenever i hit the gas, not bad or ugly, just really different, like more deep (even my girlfriend noticed it, so its really different).
What could have changed, or what could i check to try to find out whats going on?

Long story:
I have a 2008 Lancer GTS, just above 72,000 KM, it was time for a service but it only included oil change and tire rotation according to the manual and dealership representative, it was very expensive there so i took it somewhere else (a GreaseMonkey).
I saw the whole process and i think the guy did just what he was suppoused to do (I know next to nothing about car mechanics), he changed the oil filter, let the old oil out of the engine, put in the new, took out the air filter, "cleaned" it and put it back. nothing funky or strange (again, i know next to nothing about these things). then the tires were swapped.
the only thing "different" is that the oil cap on the engine says it should use 5w-30 and the guy used 10w-30. he said it was better because the hot weather we have here.
But, the car is really making a different noise whenever it goes above 2000rpm, i want to take it back but dont want to just ask "something is wrong", id like to have a few pointers from guys who know about this. so... What do you guys think? any ideas what could be causing the difference in the usual noise? Is there a possibility that the air filter was installed backwards or something? im lost.
For extra points: Do you usually take the car to the dealership for maintenance or do you go to a different place?

Thanks!
P.S. English is not my first lenguage, i translated literally from mine so excuse if some technical words are not the right ones, also excuse grammar :)

The EXACT same thing has happened to me. I dont know alot about cars, took it to the corner oil change instead of the dealer. He used 5W20 SytecBlend just like the dealer has used, and now it is making the exact type of sound you have described. Did the sound go away, what did you do about it?

Thanks for any help.

if it says use 5w30, then use 5w30 not any other oil grade...the manufacturer did not say that use 10w30 when the weather is hot.....maybe thats the reason why your car is reacting differently, coz 10w30 is thicker grade of oil than 5w30...just change the oil to what is recommended to your car and lets see if will back to normal..

I took the car back to the oil change shop and had them inspect it. The cover for the air filter was not on completly at the bottom. A quick readjustment and problem solved.