I'm not sure where this belongs but, I ordered some ford factory tow hooks for my 04 expedition. they are from 04-07 f-150's. My questions is what size bolts do I need to install them, they didn't come with any hardware.

 

Not sure of the size, but you will need 2 bolts and a backing plate for the bolts to go into. The plate fits inside the frame. Also make sure you get the 8 hard bolts. Don't want the bolt to snap when you are using the hooks.
If unsure, you could probably get the hardware from Ford or of a junkyard donor.

 

the backing plate is going to be fun trying to track one of those down, unless i go to ford.

 

The grille guard manufacturers have a set up where they weld a steel 1/4" bar to a nut and you slip it thru a hole in the side of the boxed frame. That allows you to bold up the hooks. They use those for the trucks that don't have hooks, like 2wd trucks.

 

If it was me I would simply measure the pilot hole size in the tow hooks and get a bolt 1/16" smaller than the hole. Ford probably designed the hooks to use metric fasteners though . Make sure to use grade 8 (metric 10.9) bolts made in USA or Canada. Chances are you'll need to buy them at a fastener store places like Home-Depot, etc. usually only sell grade 2 China junk. A backing plate as previously mentioned is a good idea too.
Good article here on bolt grades:
http://www.rockcrawler.com/techrepor...ners/index.asp

George