I accidentally put 5w 30 oil in my 2010 F150 today with the 4.6 engine. [grabbed the wrong gallon jug] -- Yeah, I know ... stupid.
I haven't run the engine yet. Do I drain it out and put in the 5W 20, or will it hurt?
If how I plan to use the truck has any bearing..... I am soon leaving on a trip from the north country to south Florida for a few weeks.

 

It won't hurt anything.

 

I do thank you for that answer as that was the one I was hoping for. However, in the meantime I decided it was easy to drain the 5-30 and use the what Ford suggests since I had it here. I'll use the 5-30 in my old Ranger.
Appreciate your reply however.

 

Ford just suggests that for CAFE purposes. I've run plenty of 10w-30 in my 4.2 on my SuperCab with no issues ever and probably run 5w-30 on occasion in my SCrew. No big deal.

 

Well, if that's a 3 valve 4.6 it's a good idea to use the recommended 5w20, CAFE is not the only reason, it's the %$#&^* VCT system. The 4.2 doesn't care what you put in it as long as it's oil. It's not a high tech OHC engine, it's old school pushrods.