just starting to notice a pinging when i go up an incline so i took to my local shop and said that's normal for a Ford,so i check the manual and it does say that.He said just put a higher octane maybe every other time when you fill up,does this sound right to you guys.

 

Increasing gas octane is one way to deal with it as long as the engine is running as designed. Pinging can be the result of engine components being out of specifications also.

http://www.autosite.com/garage/repairqa/ques041.asp

Does your pinging sound anything like this?

http://www.sounddogs.com/previews/17...UNDDOGS_To.wma

 

Your getting into that time of year that gas formulation is changeing to a winter mix.
This makes the gas combustion a bit quicker.
My guess is the computer will eventually readjust for this on 87 grade.
There is a knock sensor that is supposed to retard timing when detected but it could be out of tolerence.