Hi all, I have a stripped out driver side rear oil pan corner bolt on my 55 Chevy pickup with a 235. I've got a seepy oil pan so I decided to retorque all of the oil pan fasteners to spec...this is how I found it. Luckily it wasn't stripped to where it wouldn't back out.

I got it out but most of the threads on the bolt are gone.

I'm hoping the block isn't to buggerd up and I can run an tap in there to clean it out...maybe get away with an easy repair.

I've been searching for the bolt size/thread so I can use the correct tap but I can not seem to find it. I know the corner pan bolts are a little bigger then the flange bolts. I believe the flange bolts are 1/4-20.

I really don't want to mess with the other corner bolts...they all torqued to spec, I'd like to leave them alone now.

It looks like the corners might be a 5/16-18 bolt. Can anybody confirm or correct me on that. I can't really tell for sure because like I said the threads on the bolt that came out are pretty much gone.

Thanks guys....




1955 Chevy Cameo
235 engine
3 speed transmission