1984 Toyota Land Cruiser Problems: 5 Known Issues

On the 1960-1984 Toyota Land Cruiser, rust is the single biggest enemy of an FJ40 restoration and follows a predictable pattern across every year of the run. The thin factory steel and lack of cavity protection let water collect in the rear quarter panels (the lower 'dogleg' ahead of the rear arch), the rocker panels/door sills, the floor pans and seat risers, the rear wheel-well lips, the body mounts, and the cowl/firewall vent area. Mud and salt pack into the boxed rockers and double-skinned quarters, so cars that look 'rust-free' from outside are frequently rotten from the inside out. Because the frame also carries every off-road load, frame rail and crossmember corrosion is structural, not cosmetic. Untreated, the tub loses its structural integrity and door/tailgate alignment goes away.

On the 1960-1984 Toyota Land Cruiser, the factory FJ40 cooling system was marginal when new and is badly outmatched today, especially in hot climates, in traffic, or after an engine rebuild. The stock 2- or 3-core radiator simply doesn't have enough surface area to keep the long, torquey F/2F six cool, and the engine-driven flex fan is small and inefficient. Trucks that have sat for years frequently develop blocked water jackets and a silted/scaled radiator core, which compounds the problem so the engine only overheats once ambient temps climb. A failed thermostat, a tired water pump, or air trapped during refill (the system needs proper bleeding) round out the common causes. Chronic overheating risks warped heads and cracked blocks on these irreplaceable engines.

On the 1960-1984 Toyota Land Cruiser, the FJ40 uses a solid front axle with closed 'birfield' constant-velocity joints inside steering knuckles that pivot on trunnion (king-pin) bearings. These knuckle bearings carry a large share of the vehicle's weight and take constant abuse, so over decades the races wear a groove in the straight-ahead position and the birfields wear on one loaded face. The result is steering that no longer self-centers, clicks/clunks on full lock, and front-end vibration. Compounding it, the knuckle inner seals/felt wipers leak gear oil and let grit in, which accelerates wear and contaminates the birf grease. Neglected, a worn birf can eventually crack a cage or shed a ball off-road.

On the 1960-1984 Toyota Land Cruiser, vague, wandering 'death-wiggle' steering is one of the most universal FJ40 complaints. The factory recirculating-ball steering box wears in its sector shaft and worm over decades, develops play and starts to leak, while the surrounding linkage — tie-rod ends, relay (drag) link ends, the under-hood steering U-joints, and the spring bushings — also wears and stacks up slop. The dangerous DIY mistake the forums warn against is simply cranking the box's adjustment screw to remove all free play: that binds the gear on-center and rapidly destroys the sector shaft, killing the box. Manual-steering early trucks feel especially heavy and imprecise with this wear.

On the 1960-1984 Toyota Land Cruiser, the earliest FJ40s left the factory with a low-output generator (and on some markets a 6-volt or externally-regulated system), and even the later factory alternators are only rated around 38–55 amps. That is nowhere near enough once you add electric cooling fans, modern lighting, a winch, or accessories — the result is dim lights, a slowly drained battery and a cooked, brittle decades-old wiring harness. The stock harness was designed around the small factory alternator, so simply bolting on a high-amp unit and feeding it through the original wiring overloads and overheats the OEM harness. Old bullet connectors, ground points and the external regulator are common no-start and flicker culprits.