I may have screwed up, but here it goes. i changed my oil for the first time in my 2005 mustang gt. I looked in the owners manual and it says use 5w20 but really only states explicitly that i should use motor oil for gasoline engines. so i bought some pennzoil 5w20, 5 quarts. I realized when I checked the stick it wasnt enough so i drove in my second car to get another quart and asked the advanced worker to look up how much i should have. he told me 6 quarts of synthetic blend. i didnt know i needed syn blend so, I checked the manual again and saw in super fine print synthetic blend on the bottle.

Am i screwed or is it ok? at least for a week.

 

You should be absolutely fine. Heck you could run it longer than a week if you wanted, though synthetic does offer a bit of extra protection.

Synthetic blend is the factory fill and what's recommended, which is why it came up.

 

Thanks glad I got a reply to put my mind at ease

 

I would just run the oil you have until your next oil change. You won't hurt anything.

 

Thanks. One thing that had me worried and my main reason for changing it was that I had a nasty sounding ratle on cold starts. Sounded like a diesel motor unless I warmed it up. I have heard it somewhat common with the 4.6 motor

 

Sorry for the double post but it wont let me edit on my phone.

Meant that the rattle was before I changed the oil and still present