Drive Train '79 351 W w/ '92 Mustang Cobra EFI, NP435 4spd Bronco Dana 20 transfer case NP203 range box dblr High pinon F-150 Dana 44 cut down for Bronco Curry extreme duty 9" rear 4.10 gears w/ Detroit Lockers. BFG Mud 35". 135 to 1 crawl ratio.