[spinne1]

There is a stud with threads on both ends that screws right into the manifold, and then then there is a nut on the other end. They are prone to be difficult due to rust/heat exposure. For me to get it off, I first spray liberally with PB Blaster and let soak for a while. I then just use a breaker bar, 15mm impact socket and several extensions under the vehicle with the vehicle up on ramps/jack stands. I use about 2 feet worth of extensions I would guess. After I get it intially busted free and turned a couple times I pull out my impact ratchet and spin those babies free in less than a second per side. Sometimes the stud will come off with the nut and other times the nut will come off by itself. It does not matter. Do not worry about separating the nut and stud if they are stuck. Just reinstall the same way in the same spot and it will be fine.