I hit my first 1000 miles had so far (knock on wood, plastic,metal or whatever) I have had no issues even with the aluminum steering box and am averaging 19.7 mpg. So....so far so good.
I got 3 cans and did the same as what you did.. time will tell how good it works and I figure it can't hurt. Don't forget to drop your spare and do the inside of the wheel and while its down spray all under there and also the flange that holds the wheel.