My kid bought be a new ride 96 F350 4x4, bought new by his fire dept
partner. 460 stuck. Story is the former owner did a head job and
kind of lost interest. boxes of stuff . the strong bar and pry bar on the
ring gear was a no go. Anything stuck needs heat. So you will need
electric hot plate bring the atf / acetone up to sizziling boil then quickly
pour into cylinders not to much but enough to cover pistons. Then
repeat. Soon I could feel the block warm. Then strong bar on damper
clicking starter it moved about an inch then pry bar on ring gear turn
backwards (that inch) this time instead of a prybar, use a long ratchet
so if it does go it wont take your arm off. Again ratchet & starter it
broke through the inch went around like mud, then whipped around.
I did my job, now the kids turn to put all that Nasa stuff back on,cause
this things fuel injected, way past me that belongs on diesels.
So you have a better chance with 6cyl. Also take the valve covers off
and with a small block of wood see if you can pry the valves up a little.
To find this>>indications are if you can rotate or pistons move just a
little then stop, that usually stuck valves the little movement is valve
train backlash. Just a couple stuck valves is all it takes.
By the way this truck runs perfectly.