is an 88 d50 engine zero clearance???? my timing belt broke and without tearing it apart i would like to know if the valves got bent.
My understanding is no it is not an interference engine. But here is a link I found to get my answer. A little down the page it has a section in the middle that says "Interference Engine Issues" and underneath that has a link to find out if you have an interference engine or not. Hope this helps you out.
Welcome to the site. Well the g63b I'm sure is an interference engine because it's the same engine as the 4g63. I've seen bent valves a lot when the belt snaps. I don't think all engines are the same so there may be a few that is not. More info on the truck would help.