Ultimate upgrade for the 9398 4x4 crawler with pendulum steering (no servo needed). I also made a pendulum steering file in the rebrickable link you can download and have a closer look
LEGO Technic 4X4 Crawler (9398) Building Kit 1327 Pcs Truck Lego Set | eBay
LEGO® 9398 4x4 Crawler - ToyPro
LEGO TECHNIC 4x4 Crawler 9398 for Sale in Riverside, CA - OfferUp
LEGO 9398 4x4 Crawler Instructions, Technic
Ultimate upgrade for the 9398 4x4 crawler with pendulum steering (no servo needed). I also made a pendulum steering file in the rebrickable link you can download and have a closer look