This Koyorad radiator runs a core size of 427 mm high by 645 mm wide, so it drops into Nissan Pathfinder and Navara WD21 bays without drama and keeps coolant moving on long hill pulls and slow tracks. A 26 mm core thickness gives enough volume for touring loads while still clearing factory fans and shrouds. The 35 mm inlet and outlet suit standard hoses, so you keep the existing plumbing on the rig.

The tanks and tubes spread coolant evenly across the 26 mm thick core so hot spots around cylinders are less of a worry when you tow or crawl in low range. The integrated transmission cooler in the lower tank handles auto fluid temperature while the main core covers engine duty across that 427 mm by 645 mm footprint. It is smart buy gear for WD21 owners who want cooling sorted before the next big trip.

• Suits Nissan Pathfinder/Navara WD21 applications from 1996-on (as listed)
• Core height of 427 mm for factory-style airflow coverage
• Core width of 645 mm to suit original radiator support
• 26 mm core thickness balancing coolant volume and warm-up time
• 35 mm inlet neck for direct connection to OEM upper hose
• 35 mm outlet neck for direct connection to OEM lower hose
• Integrated transmission cooler circuit for compatible automatic models
• Radiator layout suited to 4x4 touring and towing use
• Direct replacement-style dimensions minimise custom fabrication
• Koyorad brand cooling gear for 4x4 and touring setups

Q: Does this radiator fit all WD21 Pathfinder and Navara engines?

It fits WD21 Pathfinder/Navara applications matching the listed core size and hose diameters. Always compare your original radiator measurements to the 427 mm x 645 mm x 26 mm core before purchase. Check that your existing hoses are 35 mm internal diameter at both inlet and outlet. If your vehicle has different tank layouts or mounting points, this unit may not suit.

Q: Is the transmission cooler suitable for heavy towing work?

The integrated cooler is built for standard automatic transmission use. For frequent heavy towing, many owners pair the in‑tank cooler with an additional external cooler. This setup helps keep automatic fluid temperature under control on long climbs. A transmission specialist can advise on exact cooling needs for your vehicle and tow weight.

Q: Can I reuse my original radiator cap and hoses?

You can usually reuse hoses and caps if they match the 35 mm necks and are in good condition. Many owners take the opportunity to replace old hoses and caps while the system is open. Fresh rubber parts reduce the chance of future leaks. A cooling system pressure test after installation confirms everything is sealing properly.

Q: Do I need to use a specific coolant type with this radiator?

You should use the coolant type specified in your Nissan owner manual. Sticking with the recommended coolant protects aluminium and other metals in the system. Always mix concentrate to the correct ratio with clean water. A full flush before fitting a new radiator helps remove old deposits and extends service life.

Suitable for Nissan Pathfinder/Navara WD21 models from 1996 onwards that match the listed manual transmission and automatic petrol applications (M/T, A/P). Verify core size of 427 mm x 645 mm x 26 mm and 35 mm inlet and outlet diameters against your existing radiator before installation. Professional installation is recommended to ensure correct hose routing and connection to the transmission cooler where required. Always refill and bleed the cooling system to manufacturer specifications after fitment.