The first thing I did after buying the truck was address the cooling system. The 1FZ-FE has a well-documented weakness: the head gasket can fail if the engine overheats, and a head gasket job on these is expensive. The best prevention is keeping the cooling system in perfect shape.
What I Replaced
- Radiator — The original was 28 years old with visible corrosion around the tanks. Replaced with a new aluminum-core unit for better heat dissipation
- Water pump — Replaced along with the timing belt service since it’s driven by the same belt
- Thermostat — New OEM-spec thermostat to ensure proper operating temperature
- All coolant hoses — Every rubber hose in the system was original and showing age cracks. Replaced upper, lower, heater hoses, and all bypass lines
- Coolant — Flushed the entire system and filled with Toyota red long-life coolant
Why This Was First
On a truck with 200,000+ miles, the cooling system is the single most important maintenance item. Everything else can wait — the engine can’t survive an overheat. Now I can drive mountain grades in summer without worrying.