How's it going fellaz. Yesterday I purchased a 78 longbed with a 350 and 350 tranny.

When I first started the truck up, in Park, there was a Very loud knock that sounded like it was coming from the back of the motor, flywheel area.

When I put the truck in drive and drove it around the block the knocking went completely away, but when I'm switching gears from Park to Reverse to Drive there's a very loud popping noise right before she starts rolling.

I drove the truck home 30 min away with no issues(not even knocking) so at this point I'm thinking its either a cracked flywheel or somethings up with the trans.

I havent crawled under her yet to see if theres anything obvious but ill let you guys know when I do so.

Really Interested in what you guys think about the popping because I couldn't find anything on that. Any help is appreciated. Thanks!

Here's some pics.. I think its a nice project for $500.