I've spent thousands on my Nissan Patrol and it's still overheating!

I’ve spent thousands on my Nissan Patrol and it’s still overheating!

Geez, the number of times Jimmy and I have had customers tell us they’ve spent up to $4,000 replacing radiators, water pumps, fan hubs and thermostats on their Nissan Patrol — and it’s still overheating! It never ceases to amaze us. By the time they speak to us, we’re almost 100% sure we can pinpoint the cause.

Short answer: if your Nissan Patrol is still overheating after new radiators, pumps and thermostats, the culprit is usually dirty engine oil, sludge and cooling-system scale — not the parts you’ve replaced. Clean the oil and cooling system first, and these problems are often solved quickly and cheaply.

Why Go Through an Expensive Trial-and-Error Process?

Why do mechanics and radiator shops almost never consider the engine’s lubrication system? It’s no secret that one of the engine oil’s duties is cooling. At Cost Effective Maintenance, we have a general rule when it comes to engine problems:

“Make sure everything is clean first, before you go spending big dollars elsewhere.”

Diesel engines can accumulate a lot of sludge and carbon deposits, which inhibit efficient cooling by the oil. The oil itself can be heavily soot-loaded — and it’s a myth that all diesel oil should go black straight after a change. Soot absorbs and retains a lot of heat rather than dispersing it. The cooling system internals can also be contaminated by mineral scale deposits, which strongly inhibit cooling ability.

And if the vehicle has changed coolant types without thorough removal of the first type, the two can react and cause sludgy deposits. If customers had spent just $199 on our Overheating Value Pack first, instead of replacing all the big-dollar cooling system components, they’d have saved themselves thousands of dollars and a heap of time.

“Instantly noticeable is the increase in oil pressure and the lower temp my GQ Nissan Patrol now runs at. This is a godsend, because she was starting to get a little hot under the collar on hot days and longer inclines!”

— Shane Cusack, GQ Nissan Patrol

It’s as simple as an oil change: use Flushing Oil Concentrate to get rid of the engine goo, and add a bottle of RMI-25 to the cooling system to get it properly clean. Add a small dose of AW10 Antiwear to the fresh oil to minimise frictional heat, and these sorts of overheating problems are solved quickly and cheaply.

It’s surprising just how common oil-related overheating issues are. Any diesel can be affected — including Toyotas, Mitsubishis, Mazdas and Land Rovers, and even heavy-duty trucks and earthmovers. For the full explanation of why dirty oil causes overheating under load, see the real cause of diesel overheating problems.

I’ve spent thousands on my Nissan Patrol and it’s still overheating!