I lost one of my down pipe bolts the other day. I need to get a new one but without taking the other one out I dont know what size to get. They look to be a metric standard thread bolt? I threaded in standard size bolt and it seemed a little loose. Please help I got soot all over under my hood.

 

M8x1.5? (this is just an educated guess)....


What year is your truck?

 

The ones that come up from the bottom and hold the exhaust in place on the flange are M10 X 1. Just not sure they are the ones your askin about.