I know it's been asked before, curious if anyone has any exact measurements, however, for the o-rings for the oil cooler lines at the radiator. Mine crumbled in my hands when I pulled the cooler lines off. Some people say you can't get them local, really hoping that's not true as I need to install my new radiator today D: Cheers!

 

14mm OD
11mm ID
1.5mm cross section.

get something that is 70 or 90 durometer in hardness that is oil and heat resistant. There is 10-12 on the whole truck I believe between the oil and transmission cooler lines.

https://www.mcmaster.com/#1247n121/=1c9m482

HTH