The Complete Guide to RB26DETT Maintenance

The Complete Guide to RB26DETT Maintenance

The RB26DETT powers the Nissan Skyline GT-R — one of the most legendary performance cars in history. This 2.6-liter twin-turbocharged inline-six produced 276 horsepower (officially) in the R32, R33, and R34 GT-R. With proper maintenance, it runs reliably for hundreds of thousands of kilometers. Neglect it, and you face repair bills that dwarf the car's purchase price.

Understanding the RB26DETT

• Configuration: Inline-six, DOHC, 24-valve
• Displacement: 2,568cc
• Bore x Stroke: 86mm x 73.7mm
• Block: Cast iron, closed-deck
• Head: Aluminum
• Turbochargers: Twin Garrett T25 (R32), twin T28 (R33/R34)
• Factory boost: 10 PSI
• Official power: 276 HP at 6,800 RPM (actual: 300-320 HP)
• Torque: 260 lb-ft at 4,400 RPM
• Individual throttle bodies (ITBs) — six butterflies, one per cylinder

Oil System

The oil system is the most critical maintenance area. Oil starvation under high-G cornering is a real concern.

Oil change: Every 5,000 km or 6 months. After every track day regardless of mileage.

Recommended oils: Street: Motul 300V 5W-30, Pennzoil Platinum 5W-30, or Mobil 1 0W-40. Track: Motul 300V 15W-50 or Driven DT40 5W-40. Capacity: 4.5 liters with filter.

Oil filter: Nissan OEM 15208-65F0E. Change every time without exception.

Oil cooler: Factory unit is adequate for street use. For track, add an aftermarket cooler (GReddy, HKS, or Setrab) with -10AN lines and thermostat. Keep oil below 120 degrees Celsius under load.

Cooling System

The RB26 runs hot, particularly around cylinders 5 and 6.

Coolant: Change every 2 years or 40,000 km. Nissan OEM Long Life Coolant or quality ethylene glycol, 50/50 with distilled water.

Thermostat: Replace every 60,000 km. Factory opens at 76.5 degrees. Nissan 21200-42L01.

Radiator: The N1 radiator is a common upgrade. For serious cooling, aluminum dual-core from Koyo (HH020879) or CSF.

Water pump: Replace every 100,000 km or at timing belt service. Nissan 21010-24U27.

Hoses: Replace all coolant hoses at 100,000 km or 15 years. Samco silicone kits are a worthwhile upgrade.

Timing Belt Service

The RB26 uses a timing belt — not a chain — and failure is catastrophic (interference engine). This is the single most important scheduled maintenance item.

Interval: Every 100,000 km or 8 years. Many experienced owners replace at 80,000 km for safety margin.

Replace during service:

• Timing belt (Nissan 13028-05U10 or Gates T215)
• Tensioner (Nissan 13070-05U00)
• Idler pulleys (2x, Nissan 13073-16A00 and 13077-16A00)
• Water pump (Nissan 21010-24U27)
• Front main seal (Nissan 13510-05U10)
• Cam seals (6x, Nissan 13042-05U00)
• Alternator and power steering belts

Total cost: Parts $400 to $700. Labor at a GT-R specialist: $800 to $1,500. Total: $1,200 to $2,200.

A snapped belt destroys all 24 valves and may crack pistons. The repair exceeds $5,000 — far more than preventive maintenance.

Turbocharger Maintenance

R32 GT-R: Ceramic-wheeled T25 turbos that can shatter without warning at high mileage. If your R32 still has original ceramic turbos, budget for replacement.

R33/R34 GT-R: Steel-wheeled T28 turbos. More durable, reliably lasting 150,000 to 200,000 km with proper oil changes.

Signs of wear: Blue or gray smoke on deceleration, excessive shaft play, whining or grinding under boost, loss of boost pressure.

Rebuild vs. replacement: Factory rebuild: $500 to $800 per turbo. New aftermarket: $1,200 to $2,000 per turbo.

Ignition System

Spark plugs: Replace every 20,000 km. Factory: NGK BKR6EP-11. For modified engines above 15 PSI: NGK BKR7E. Gap: 0.8mm stock, 0.7mm for higher boost.

Coil packs: Factory coils (Nissan 22448-25U00) weaken with age. Misfires under load indicate failure. R35 GT-R coil pack conversion is a popular upgrade requiring adapter harnesses ($200 from Raceoptix or WireWorx).

Fuel System

Fuel filter: Replace every 40,000 km. Nissan 16400-41B05.

Injectors: Factory 444cc, adequate for stock power. Clean or replace at 100,000 km. For builds exceeding 400 hp: Injector Dynamics ID1050X or DeatschWerks 1000cc.

Fuel pump: Factory supports stock power. For 400+ hp: Walbro 450 or AEM 340LPH.

Regular Inspection Checklist (Every 10,000 km)

• Engine oil level and condition
• Coolant level (check for oil contamination)
• Boost leak test (pressurize to 15 PSI, listen for leaks)
• Turbo shaft play inspection
• Vacuum hose condition (dozens of hoses that crack with age)
• Exhaust manifold gasket (ticking at cold startup)
• ATTESA E-TS fluid level (transfer case)
• Brake fluid (flush every 2 years with DOT 4)
• Differential oil (replace every 40,000 km with 80W-90 GL-5)
• Transmission oil (replace every 40,000 km with 75W-85 GL-4 or Redline MT-90)

The Bottom Line

The RB26DETT is one of the most robust performance engines ever built. Its cast-iron block handles abuse that would destroy lesser engines, and its mechanical simplicity makes maintenance accessible. Respect the schedule, use quality fluids and parts, and address problems early. Your RB26 will reward you with decades of reliable, exhilarating performance.