The Koyorad JR2828J radiator steps in when the factory Lexus RX400H cooling setup starts to struggle, with a core height of 675 mm and width of 474 mm that lines up with the original mounts. The 22 mm core thickness suits everyday commuting and weekend trips where the hybrid V6 still builds heat in traffic or on climbs. The automatic RX400H from 2006 to 2008 takes this unit as a straight cooling replacement. This radiator backs that use with a 34 mm inlet and 38 mm outlet so your existing hoses clamp straight on. The built‑in transmission cooler keeps the auto gearbox tied into the same shell, which keeps the plumbing tidy and familiar. The dimensions mirror the standard RX400H layout so fans and shrouds sit where they should. If you want a smart buy that matches factory sizing, this Koyorad unit fits the brief.

• Suits Lexus RX400H 2006–2008 automatic models
• Core height measures 675 mm for strong cooling area
• Core width of 474 mm matches factory mounting
• Core thickness of 22 mm balances flow and airflow
• 34 mm inlet neck suits OEM upper hose
• 38 mm outlet neck suits OEM lower hose
• Integrated transmission cooler for auto gearbox
• Direct-fit style replacement radiator assembly
• Suitable for everyday commuting and touring use
• Koyorad branded radiator in 4x4 performance range

Q: Does this radiator include an integrated transmission cooler?

Yes, this radiator includes an internal transmission cooler circuit. That means the automatic transmission fluid can be routed through the radiator like the original Lexus RX400H setup. You will reuse your existing hard lines and fittings where they enter and exit the cooler. Always check for leaks after refilling and running the engine to temperature.

Q: Will this fit all Lexus RX400H models in Australia?

This radiator suits Lexus RX400H models built between 2006 and 2008 with automatic transmission. Build dates outside that range may use different core sizes or mounting points. Always match the JR2828J dimensions and hose positions to your original radiator before ordering. If your vehicle has had front‑end repairs, confirm that the support panel still matches factory spec.

Q: Do I need new radiator hoses with this unit?

Not necessarily, as the inlet is 34 mm and the outlet is 38 mm to match OEM hoses. If your existing hoses are swollen, cracked or more than several years old, replacing them at the same time is sensible. Fresh hoses reduce the chance of roadside failures on long trips. New clamps can also help maintain even pressure around the necks.

Q: Is this radiator suitable for towing and long highway runs?

Yes, this radiator is sized for normal towing and highway driving within the RX400H’s rated limits. The 675 mm by 474 mm core provides adequate surface area for sustained airflow at speed. The 22 mm thickness supports consistent coolant flow without excessive restriction. Always ensure the rest of the cooling system, including fans and thermostat, is in good condition for heavy use.

Suits Lexus RX400H hybrid models built between 2006 and 2008 with automatic transmission. Fitment is for the factory replacement radiator position in the RX400H front cooling stack. Installation requires transfer of original hoses, clamps, fans, shroud and sensors from the existing radiator. Professional installation is recommended to manage coolant handling and transmission cooler line reconnection. Always confirm JR2828J against your current radiator dimensions and mounting layout before purchase.