Credov's researched list of the 12 faults the Isuzu D-Max RC is known for (2012–2020), 12 of them serious or costly. Each one says what to look for when you check the car, so you can spot it before you buy. Not every car has these faults: they are the ones worth checking on this model.
What to look for: Crouch at each rear wheel and check the leaf springs for cracks at the front eye or centre bolt, or shifted leaves.
Why it matters: A broken rear leaf spring can let the axle shift, which can affect control of the vehicle and, on some crew cabs, foul the park brake cable - and the 2018-2020 three-leaf design has a documented front-eye weak point.
What to look for: Under the bonnet, torch both inner guards near the strut towers, battery tray and VIN plate for hairline cracks or fresh welds.
Why it matters: A cracked inner guard is a structural repair, not a cosmetic one: a repair quoted in Australia's class-action investigation ran to roughly A$9,722, the proper fix can need the engine removed, and some guards have cracked again afterwards.
What to look for: Run the air conditioning on max cold while idling then driving; warm air within a couple of minutes suggests a leak.
Why it matters: The fix means stripping out the whole dashboard, roughly 6-7 hours of labour, and some vehicles have gone through three or four evaporators, so an undiagnosed slow leak can mean repeat bills rather than a one-off repair.
What to look for: Listen with the window down for a siren or whine as boost builds, especially on a hard uphill pull.
Why it matters: A sticking or failed variable-vane turbo drops the vehicle into limp mode and a replacement is a major cost; repeat failures within warranty on this engine mean even a recently replaced turbo can fail again.
What to look for: Check the dash for a steady or flashing DPD light, and ask how often the vehicle needs a forced regeneration.
Why it matters: A clogged or constantly regenerating DPD raises fuel use and can push the engine into limp mode, and the underlying sensor or injector fault behind it is common enough that Isuzu's Australian market faced a class-action investigation over DPF replacement costs.
What to look for: On a cold start listen and watch for rough idle, hard starting, black smoke and slow-building boost under load.
Why it matters: A clogged EGR and intake lose power and can push combustion temperatures up, and leaving it unclean long-term is a common lead-in to an expensive EGR cooler coolant leak.
What to look for: On the test drive feel for idle hunting, surging at light throttle, or hesitation and stalling pulling away.
Why it matters: A sticking suction control valve can stall the engine or drop it into limp mode, and if water or debris has damaged the pump itself the repair extends to the injectors and a full fuel-system flush.
What to look for: With the engine idling, look and listen near each injector for black carbon build-up or a ticking, chuffing noise.
Why it matters: Worn or leaking injectors mean rough running, higher fuel use and, on DPD models, repeat forced regenerations, and a full injector replacement across several cylinders is a major bill.
What to look for: On the test drive feel for slipping, flare between gears or harsh engagement, especially if the vehicle has towed.
Why it matters: Repeated overheating while towing cooks the transmission fluid and wears the torque converter, and a worn five-speed automatic is an expensive gearbox to replace.
What to look for: On a long hill watch for repeated shifting between gears, slip or flare, and a transmission temperature warning.
Why it matters: A hunting gearbox that will not lock up overheats when towing, and the resulting fluid and converter damage is an expensive repair that software updates alone have not fully fixed.
What to look for: On the test drive change through every gear and, downhill, lift off in 2nd and 3rd to see if it pops out.
Why it matters: A gearbox that jumps out of gear, especially downhill, is both a safety concern and a sign of synchro wear that some owners have needed a full gearbox replacement to fix.
What to look for: Feel where the clutch bites, check for judder pulling away on a hill, and look under the bellhousing for leaks.
Why it matters: An early clutch failure on a hard-worked ute is a common and costly repair, and a soft pedal or judder can point to a failing slave cylinder or an oil leak contaminating the clutch.
Got a question about a Isuzu D-Max RC? Ask Credov: a noise, a warning light, a part or how to fix it.
On top of the faults above, every Credov inspection covers the basics: fuel smell, leaks or filler rust, engine oil leaks, power steering fluid leak, drive belt cracks or squeal, rust underneath: chassis and mounts, engine mounts, engine oil level and colour, coolant level, colour and leaks, head gasket failure signs, cold start: rattle, knock or smoke, rough or hunting idle, engine running hot on gauge, gearbox or diff oil leak, swapped gearbox without lvv and more.
Researched by Credov from manufacturer recalls and service bulletins, owner reports and workshop sources. Repair prices are typical ranges, not quotes. See also fault codes and repair costs.