Extreme FJ40 Build: Stretched Chassis & Custom Suspension

I learned to drive in this 1978 Toyota Land Cruiser FJ40. After 40 years, it was time to rebuild it the right way—starting with a complete 1-ton chassis transformation.

In this video, I walk through extending the frame, building a custom 3-link and 4-link suspension front and rear, and setting up King coilovers with air bumps. Every decision had a reason, and I break down the technical details that made this build work.

🔧 BUILD SPECS:
Frame extension with diagonal cuts and fish plating
Corporate 14-bolt rear axle with Ruffstuff truss
Dana 60 front axle with custom 3-link mounts
King 2.5" coilovers (replica due to supply chain)
Rock Jock Antirock sway bars front and rear
King 2.0 x 2" air bumps
PSC hydraulic steering assist
2.5" solid aluminum lower links (Wide Open Design)
2" DOM upper links

COMING UP IN THIS SERIES:
6.2L LS engine swap breakdown
ARB air locker installation
40-inch tire setup and gearing choices
Complete drivetrain walkthrough

CHAPTERS:
0:00 Video Outlook: Chassis and Suspension
0:30 The Family Legacy
1:00 Cutting the Frame
1:32 Extending and Fish Plating Techniques
1:48 Frame Extensions Complete
2:04 Plate and Weld Frame
2:32 Rear Axle Truss & Link Mounts
2:49 Lower Link Crossmember
2:59 Rear Suspension Frame Notch and Towers
4:10 Front 3-Link Configuration
5:01 Front Antirock & Air Bumps
5:44 Up Next: Drive Terrain


KEY VENDORS

These are some of the key vendors that helped make this build possible. It is not a complete list as many other parts and components came from general retailers not listed here.

• 4XInnovations
• Aqualu Industries
• Alamosa GMRS Antenna
• Altitude Speed and Fabrication
• Advanced Adapters
• ARB
• Ballistic Fabrication
• Barns 4WD
• Busted Knuckle Offroad
• DeWitts Radiator
• Eastwood Automotive Group
• EST 28 Upholstery
• JW Fabrication — https://jwfabshop.com
• Kartek
• King Shocks
• Mickey Thompson Tires
• Millermatic Miller welder and plasma cutter
• Reed Racing
• RockJock
• Rogue Fabrication
• RuffStuff
• Sidetrack Beadlock Wheels
• Steve’s Transmission
• TMR Customs
• Tom Woods Driveshafts
• Warn Industries
• WFO
• Wide Open Design
• Rugged Radios

This Land Cruiser has a long history with the family. It was the family car from when it was new until the early 1990s. Every summer we used to drive it with a military trailer behind us to the San Juan Mountains, traveling between Creede, Silverton, Lake City, and Ouray, Colorado. I bought it from my dad as my first car and drove it stock until 1999. For more than 20 years, it ran on Alcan leaf springs with a spring-over lift and 35-inch tires, tackling some of the toughest trails rated 9 out of 10. That includes Pritchett Canyon, Cliffhanger, and Golden Spike in Utah, as well as Carnage Canyon, Blanco Peak, and Holy Cross in Colorado. I would like to drive it on the Rubicon, Fordyce, multiple trails back east, and potentially all the way to Alaska someday.