Our quest to find the highest-mileage 4×4 on the road has unearthed an Irish Toyota Land Cruiser on a weighty 484,000 miles. James Andrews finds out what sort of shape it’s in.

When Farmers Weekly gets wind of a high-mileage 4×4 it’s pretty much guaranteed to be Japanese and will almost certainly be sporting a Toyota badge.

In the past few years we’ve reported on four such vehicles, all of which have eclipsed the 380,000-mile mark with little more mechanical intervention than run-of-the-mill servicing.

Three of these have been Toyotas, but perhaps the most impressive of the lot was a 1997 Isuzu Trooper on 490,000 miles.

Our latest contender, a 2008 Land Cruiser LC4 van belonging to land surveyor Hector Nelson in County Meath, Ireland, comes a close second.

He’s owned the vehicle since new – when it cost €34,000 (£30,132) – and in the past 10 years has clocked up 778,945km (484,000 miles) with it.

Most of these have been accumulated crisscrossing the Irish countryside, and to get to that prodigious figure he’s put in about 78,000km (48,500ish miles) a year, every year since new.

Durable driveline

As with previous high-mileage vehicles we’ve featured, this truck is still running its original engine and gearbox, plus a few slightly more surprising items.

These include the clutch, exhaust, turbo and all but one of the wheel bearings. It’s also only on its second battery, alternator and starter motor.

The rock-solid engine is Toyota’s 3-litre, four-cylinder D4D, known as the 1KD-FTV. These have a cast block, an aluminium head with four valves per cylinder and twin overhead cams.

Fuel delivery is through a common-rail system and it has a variable nozzle vane turbocharger. All this gives it a power output of 170hp and 410Nm torque.

Hector Nelson with his Land Cruiser © James Andrews

Injectors were this engine’s main downfall, but all four on Mr Nelson’s vehicle were replaced early on in its life under warranty, and it’s still running the same set now.

However, due to the sheer volume of fuel that’s passed through them he reckons he must be due another set fairly soon. Some of these engines have also suffered from cracked pistons, but this one appears to have escaped so far.

Keeping it fresh

One of the reasons for its longevity is its regular servicing, which Mr Nelson carries out himself with the help of his mechanically minded neighbour.

This regime includes an oil and filter change every 16,000km (10,000 miles) or so, always using the highest-grade fully synthetic oil.

Timing belts are replaced every 100,000km (about 60,000 miles) and the gearbox and diffs get fresh lube every 150,000km (about 95,000 miles).

He’s also fastidious about changing the air filter and never lets it idle for long periods when warm. “That’s a sure-fire way to glaze the bores and then it’s stuffed,” he says.

© James Andrews

The most expensive items replaced to date include a €300 (£265) driver’s airbag squib (the component that sets the airbag off) and a €200 (£177) windscreen wiper linkage.

It’s also had the usual brake and suspension parts, including a couple of new callipers.

As for the gearbox, it’s got a six-speed manual that gives considerably lower-rev motorway cruising than the five-cog version.

This combined with some fairly steady driving means it’ll average between 30 and 35mpg, he says. “I don’t thrash it as it’s me that has to foot the fuel bill, but I do give it a blast every now and again to clear its lungs.”

Bridgestone Duelers are his number one tyre choice, as these will comfortably see him through a year of motoring.

Mr Nelson has no plans to change the truck and hopes to put at least one million kilometres (621,371 miles) on the clock before he upgrades – at his current rate that should take less than three years.

Other high-milers

Here’s the league table of mile-munching motors we’ve featured in the past:

Andy Gay’s 1997 Isuzu Trooper – 490,000 miles (below)

Anthony Simpson’s 1996 Toyota Land Cruiser Amazon 80-series – 419,000 miles (below)

Peter Hanifin’s 2007 Toyota Land Cruiser 3.0 D4D GX – 397,678 miles (below)

David Wootton’s year 2000 Toyota Hilux – 387,0000 miles (below)