[tet68]

As a last resort, you might get some dry ice from
a grocery store, chip off a piece and hold it with
pliers against the bolt. This will make it contract
and pull away from the caliper, then it should come out.

[winodog]

Never heard of that but it makes sense and should allow the wd40/whiskey to soak in good

[daniel1212]

As a last resort, you might get some dry ice from a grocery store, chip off a piece and hold it with pliers against the bolt. This will make it contract and pull away from the caliper, then it should come out.

Putting it all together, quickly heat all areas of the surrounding area around the bolt just enough to allow your chosen penetrating concoction to penetrate better, but not boil off or combust.

Then, once you have the removal wrench ready, hold a few ounces of dry ice (a meat shipper may have some) as much on and nearest the bolt as possible for about 20 minutes (cover with rags as doing so). Then quickly heat the surrounding area around the bolt so that this will expand faster than the cold bolt, and then quickly spray a little of something like PB Blaster penetrating fluid, and immediately attempt to remove the bolt.

[monocle]

This is the advice I gave on an earlier thread. When taking advantage of the coefficient of thermal expansion, it should make no difference whether one uses heat or cold.

[piytar]

Great idea!