Have a Car Question? Ask a Mechanic Online.
What happens is either you have a carbon build up on the end of the glow plug or detonation has deformed it.
I cock the soket on it and justs keep spinning and pulling at the same time it can be a real pain but the alternitive is removing the head.
What engine is it a 6.9 or 7.3 Ford licenced IHC or a 6.2 or 6.5 GM?
If you have a 1/4 air rachet it makes the job a little faster, but like I said they are no fun .
If my answer was helpful please click on the accept button to complete the transaction,you can keep the post open incase you have any followup questions.