I am intending to do a visa run taking my vehicle with me. I believe that I will need a vehicle safety certificate as well as the log book. Can I get this in Isaan before crossing or do I have to go to Bangkok?

Log Book? Do you mean your triucks Blue book?

Plus

you need your trucks "purple" passport book,

its available at the transport office where you get your yearly sticker. cost 50 baht, valid for 1 year, just take your blue book, copy of your front passport page and copy of your current visa

vehicle safety certificate no idea what this is?

Good advice!