Symptoms
A coolant leak low on the driver's side of the engine, or a sudden loss of coolant that leaves you stranded. Old original clamps are a warning sign on their own.
The fix, step by step
- Follow the hard metal heater pipe from the heater valve down the driver's side of the engine.
- The PHH is the short rubber hose (about 3 in) joining that pipe to the block, below the intake manifold.
- The best view is from the driver's front wheel well.
- Replace it with quality hose and clamps.
- While you're there, do the bypass hose just above and forward of it and the formed hose under the intake.
- Slee's site has a photo write-up.
- Refill with Toyota red coolant and bleed the system.
Tools & part numbers
- Hose pliers
- long extensions
- drain pan
- coolant
- replacement hose and constant-tension clamps, or a PHH bypass kit
Where to buy the parts
Coolant bypass hose, FZJ80/LX450 (RAD16264)CruiserTeq ↗Amazon ↗
Heater hoses and fittings (search)Cruiser Corps ↗
Heater control valve, FJ80/FZJ80Cruiser Corps ↗Amazon ↗
Hunting a used or discontinued part? Search eBay Motors for Lexus LX 450 parts →
Rated for a competent home mechanic with a decent tool kit. Confirm torque figures, fluids and procedures against the factory service manual for your VIN, support the truck on stands rather than a jack, and work at your own risk (disclaimer). Some parts links are affiliate links, which pay us a small commission at no cost to you.