front brake caliper on 2006 Mercury Mariner

what size are the caliper bolts they apear to be hex bolts but 5/16 is to small 3/8 to big 8mm small 10mm to big is a special size tool required

Asked by for the 2006 Mercury Mariner
they are a 9 mm. sears has a set with that size. auto zone does not have that size.
6 more answers
It takes a 9mm hex. they are not common in sets.
Have you checked to see if has that info? They have many repair manuals online for free!
Lowe's has a set of Kobalt keys with a T-handle for like $12. Sears and autozone sets are very full sets and are over $20.
They are 9mm Allen
It is a 9mm allen, I finally found a set of Allen wrenches that included a 9mm at Home Depot for around $11, Sears did not have one, nor did O'Rielly's
These are 9mm hex bolts. Had to search for a 9mm, finally saw one at Lowes of all places, bought a set of allen wrenches. Works well.