700R4 AUTOMATIC TRANSMISSION

The 700R4 is an extremely capable transmission. It is a great transmission for rock crawling with it's 3.06 first gear.
The best cores for a 700R4 build were from 1987-92 they had all the factory upgrades that solved the lubrication issues that plagued the '86 and earlier units. It's best to get a core "K" case from a GM 4x4.