Nissan Patrol Water in Oil — GU Y61 and GQ Y60 Guide for NZ Owners

Patrol Models Affected

The GQ Y60 Patrol (1987-1997) and GU Y61 Patrol (1997-2012) remain beloved workhorses in New Zealand's high country, with the TD42 and ZD30 diesels the most common powertrains. Both engines have oil-cooler-related contamination vulnerabilities that become more likely with age and high mileage.

ZD30 — Known Issues

The ZD30 diesel in the GU Patrol has a documented history of EGR cooler and head gasket issues. EGR cooler failure can allow coolant to enter the intake system, which in some cases reaches the oil system. ZD30 head gasket failure — often associated with overheating — directly introduces coolant to the oil galleries. Many ZD30 owners have fitted aftermarket ZD30 head gasket upgrades specifically to address this.

TD42 — Generally More Robust

The naturally aspirated TD42 is significantly more robust than the ZD30. Its primary water-in-oil risk is the oil cooler, which can develop internal leaks on high-mileage examples. The TD42's cast-iron construction means it handles higher operating temperatures better, but it is not immune to flood damage — the air intake on a standard GQ is at moderate height.

EEK Service

EEK Mechanical dispatches a tow truck to collect your Patrol and takes it to the nearest certified workshop equipped for TD42 and ZD30 oil specifications. Call 0800 769 000.