CSF 7231B All-Aluminum Radiator Nissan R34 Skyline GT-R GT 1999-2002 RB26

Vehicle Fitment

• 1999-2002 Nissan Skyline R34 GT-R (RB26DETT - incl. Nismo, V-Spec, M·spec variants)
• 1999-2002 Nissan Skyline R34 GT / 25GT / 25GT-V (RB25DE / RB25DET Neo)
• 1999-2002 Nissan Skyline R34 25GT FOUR / 25GT Turbo (RB25DET Neo, AWD)
• 1999-2002 Nissan Skyline R34 25GT-X / 25GT-X FOUR / 25GT-X Turbo (RB25DET Neo)

Fitment Notes

• CSF 7231/7231B are based on the early-model R34 GT-R radiator design (slim tank profile) - they fit both early and late model R34 GT-Rs, but the fan shroud will require different mounting hardware on late-model GT-Rs
• Replaces Nissan OEM part numbers 21410-AA400 and 21410-AA401
• Mounts in the factory radiator location with no modifications or cutting required - uses all OEM mounting points and hardware; late-model GT-R fan shroud mounting hardware exception noted above
• CSF 7231B is the black powdercoat finish version - the brushed aluminum version is CSF 7231
• For the R32 Skyline (1989-1994) equivalent, see CSF 7229/7229B; for the R33 Skyline (1994-1998), see CSF 7230/7230B
• Manual transmission applications; confirm compatibility for automatic before ordering

Features

• 2-Row 42mm all-aluminum core - substantially increases coolant capacity and heat dissipation surface area over the factory R34 radiator, providing meaningful thermal headroom for modified and high-boost RB25 and RB26 builds
• CSF's exclusive B-Tube technology - seam-brazed B-shaped tube cross-section increases heat transfer surface area by approximately 15% over conventional oval welded tubes, delivering dual liquid laminar flow within the same core footprint
• Ultra-efficient multi-louvered fins maximize airflow through the core for sustained cooling performance under track, street, and high-boost conditions
• High-grade aluminum end tanks, TIG-welded to the core - strong, durable construction that withstands the thermal cycling and pressure demands of turbocharged RB-series builds
• Pre-plugged 1/8" NPT port on the top end tank for optional coolant temperature sensor installation
• M16x1.5P port on the bottom end tank for optional coolant temperature sensor installation
• Black powdercoat finish - thermal-rejection coating and a stealthy, aggressive appearance well-suited to modified and track-oriented R34 builds
• Drop-in fit: mounts to all factory brackets and accepts factory radiator hoses - no modification required on early-model GT-Rs; late-model GT-Rs require different fan shroud mounting hardware

Specifications

• Part Number: CSF 7231B
• Part Type: High-Performance All-Aluminum Radiator (CSF 7000-Series)
• Construction: 2-Row, 42mm core, B-Tube, TIG-Welded, All-Aluminum
• Finish: Black Powdercoat (thermal-rejection)
• Tank Design: Early-model R34 GT-R slim tank profile
• Sensor Ports: 1/8" NPT (top tank, pre-plugged); M16x1.5P (bottom tank)
• OEM Cross Reference: Nissan 21410-AA400 / 21410-AA401
• Application: 1999-2002 Nissan R34 Skyline GT-R / GT / 25GT (RB25 / RB26)

Included Components

• 1x CSF 7231B High-Performance All-Aluminum Radiator (black powdercoat finish)

Product Description

The CSF 7231B is the black powdercoat variant of CSF's high-performance all-aluminum radiator for the 1999-2002 Nissan R34 Skyline, covering GT-R variants (RB26DETT, including Nismo, V-Spec, and M·spec) and the full range of GT, 25GT, and 25GT-X variants equipped with the RB25DE or RB25DET Neo inline-six. As part of CSF's 7000-series Racing & High Performance Division, the 7231B uses a 2-row 42mm core with CSF's proprietary B-Tube technology - a seam-brazed B-shaped tube cross-section that increases heat transfer surface area by approximately 15% over standard oval-welded tubes and creates dual liquid laminar flow within the same package dimensions. The result is substantially greater cooling capacity than the factory unit, with the headroom needed to manage heat output from modified and high-boost RB-series powerplants.

The black thermal-rejection powdercoat finish gives the 7231B a clean, purposeful appearance that suits modified engine bays and track builds where aesthetics matter alongside performance. The 7231B is based on the early-model R34 GT-R slim tank radiator design and fits both early and late model R34 GT-Rs - however, late-model GT-Rs require different fan shroud mounting hardware for installation. Pre-plugged 1/8" NPT and M16x1.5P sensor ports on the end tanks allow optional coolant temperature monitoring. Replaces Nissan OEM part numbers 21410-AA400 and 21410-AA401. The brushed aluminum version is CSF 7231. R33 Skyline owners should reference CSF 7230/7230B; R32 owners should reference CSF 7229/7229B.