Hi, Guest
When it comes to fitment H4 and 9003 are the same.
When it comes to light output, I dunno maybe different.
The best thing to do if you are completely at a loss, take one of your bulbs out, take it in to the store and match it up.
Your bulb should have a marking somewhere that says 9003 or whatever.
As for your manual saying somethng else, perhaps it is a ploy to throw people off and cause confusion so you will go to your local Ford dealer to get them replaced.
Hope that helps...
When it comes to light output, I dunno maybe different.
The best thing to do if you are completely at a loss, take one of your bulbs out, take it in to the store and match it up.
Your bulb should have a marking somewhere that says 9003 or whatever.
As for your manual saying somethng else, perhaps it is a ploy to throw people off and cause confusion so you will go to your local Ford dealer to get them replaced.
Hope that helps...