P1778 RE5R05A Patrol Y61

Vlad Ivanov — Sun, 03 Aug 2025 00:59:20 +0000

P1778 RE5R05A – Is It Just a Solenoid or the Start of a Bigger Problem?

What Does P1778 Mean?

The P1778 code on vehicles equipped with the RE5R05A 5-speed automatic transmission (found in Nissan Patrol Y61, Pathfinder R51, Navara D40, and Infiniti FX/QX) signals a torque converter lock-up performance problem or control solenoid fault.

While some drivers hope it’s “just a solenoid,” this code is usually a symptom of deeper problems, like torque converter clutch wear or valve body cross-leak, which affect line pressure and smooth lock-up.

Typical Symptoms of P1778

Light shudder or vibration during highway cruising (80–100 km/h).

Harsh or delayed shifts, especially 2nd–3rd under load.

RPM fluctuations while maintaining steady throttle.

Heat build-up or overheating warning lights on heavy trips.

Fluid that is dark or smells burnt, often with fine metallic debris.

What Causes P1778?

1. Torque Converter Lock-Up Clutch Wear: The TCC lining deteriorates, causing slip and heat.

2. Valve Body Solenoid Fault: Solenoids fail due to bore wear and fluid contamination.

3. Pressure Leaks: Cross-leaks in the valve body reduce TCC holding power.

4. Fluid Breakdown: Overheated fluid reduces lubrication and accelerates wear.

What Happens If You Ignore It?

Torque converter failure progresses, leading to P0741 lock-up faults.

Rear clutch pack (C2/C3) damage due to prolonged slipping.

Full transmission failure, requiring a costly rebuild.

The Redorq Solution for P1778

Our $285 Redorq Scan + Dyno Diagnostic pinpoints whether P1778 is caused by solenoid wear, torque converter slip, or line pressure faults.

The recommended TQ+VB rebuild package includes:

• Remanufactured HD Torque Converter – with upgraded lock-up clutch lining.

Valve Body rebuild or exchange – correcting solenoid faults and cross-leaks.

Full clutch pack replacement (C1–C3) if necessary.

Transmission cooler upgrade to prevent heat-related repeat failures.

Pre- and post-repair dyno tests for complete validation.

Typical cost: $4,700 – $5,300 inc GST for a complete TQ+VB rebuild including cooler upgrade.

Why Choose BTT for P1778 Repairs?

Specialists in RE5R05A transmissions for Patrol, Pathfinder, Navara, and Infiniti FX/QX.

Dyno-based fault confirmation eliminates guesswork.

Upgraded solutions designed for towing, off-road, and high-heat conditions.

Book Your Scan + Dyno Today

Don’t gamble on whether P1778 is just a solenoid — often, it’s the start of something bigger. Call Brisbane Tuning & Turbo or Book Online now to schedule your $285 Redorq Scan + Dyno Diagnostic. Click here to get our contact details.

P0741 Nissan Patrol – The Lock-Up Code That Signals Converter Failure.

Pathfinder R51 Transmission Problems – What Every Owner Should Know.

RE5R05A Transmission.

Сообщение P1778 RE5R05A Patrol Y61 появились сначала на Brisbane Tuning and Turbo Centre.

p1778-re5r05a-patrol-y61 - Brisbane Tuning and Turbo Centre