Mitsubishi Legnum: common faults & what to check

Which Mitsubishi Legnum are you looking at?

1 generation variant documented. Pick the shape you recognise: the faults, the servicing and the timeline below all narrow to it. Free, no account needed.

Engine not documented

1 variant documented

1996–2005EA1996–2005EAEngine not documented for this generationEngine not documentedDocumented issues6 knownSee faults & what to checkPhoto: TTTNIS via Wikimedia Commons, Public domain.

Now narrow it to the engine

A 1.8 and a 2.4 of the same car do not fail the same way, so the faults below narrow to the engine as well as the year. Free, no account needed.

Start your free check on this Mitsubishi Legnum

No plate needed. You get the risk score, the buyer's checklist and the guided inspection for the exact car you picked above — not the whole nameplate.

The checks worth doing on a Mitsubishi Legnum before you hand over any money. Every documented fault is listed below, each with its own page.

• Serious issue

  Inspect rubber boot condition; a cracked or missing boot means immediate grease loss and near-term failure.

  See why

  Front Lower Control Arm Ball Joint Failure

  Front lower arm ball joints on the Legnum EC5W develop play and eventual separation as rubber boots crack and grease is lost. At 20+ years old, most NZ-imported examples are well past the useful life of original ball joints. Separation at speed causes immediate loss of steering control and is a WOF failure point. The condition worsens rapidly once boot integrity is lost.

  What you would notice

  • Clunking noise from front suspension over bumps or during cornering
  • Vague or wandering steering feel
  • Uneven tyre wear across the front axle
  • Vibration through steering wheel on rough road surfaces

  Typically $280–$600 to put right.

• Serious issue

  Demand a dated timing belt replacement record — a sticker on the radiator shroud or stamp in the service book.

  See why

  Timing Belt Failure — Interference Engine (6A12 V6 / 4G93T)

  Both the 6A12 V6 and 4G93T engines fitted to the Legnum EC5W are interference designs; belt failure causes immediate piston-to-valve contact resulting in bent valves and cylinder head damage. Japanese-market imports frequently arrive with unknown or unverifiable service history. The 4G93T turbo variant runs higher thermal and belt loads, further shortening belt life from heat cycling. The service interval is 90,000 km or 5 years, whichever comes first.

  What you would notice

  • Engine stops suddenly with no restart
  • Loud mechanical bang at moment of belt failure
  • Engine cranks freely but will not start post-failure
  • No compression on multiple cylinders after failure
  • Rattling from timing cover area on worn tensioner bearing

  Typically $600–$6,500 to put right.

• Serious issue

  Manually spin each idler pulley checking for bearing roughness, noise or wobble.

  See why

  6A13TT Timing Belt Tensioner & Idler Bearing Failure

  The Legnum EC with 6A13 2.5L twin-turbo DOHC V6 is a fully interference-configuration engine where timing belt failure causes immediate and total engine destruction through piston-to-valve contact. The hydraulic auto-tensioner loses its internal damping as seals age, while the idler bearings are subject to accelerated degradation in the turbocharged thermal environment — turbo heat soak raises ambient underbonnet temperatures well beyond naturally aspirated equivalents, breaking down bearing grease faster. The dual overhead cam arrangement also places greater rotational load on the belt than a single-cam engine. Many NZ-imported Legnums arrive with incomplete Japanese service records, and the labour-intensive cover removal process means this critical service is frequently deferred or skipped.

  What you would notice

  • High-pitched chirping or ticking at idle from timing belt cover area
  • Belt slap or rattling noise on cold start settling after warm-up
  • Engine misfires or rough running if belt has jumped teeth
  • Complete engine stall and refusal to restart on full belt breakage

  Typically $750–$1,600 to put right.

• Costly issue

  Visually inspect the inner bush for rubber extrusion beyond the steel shell, visible cracking, or gaps between rubber and shell.

  See why

  Front Lower Wishbone Inner Bush Collapse

  The Legnum EC front double-wishbone suspension uses pressed rubber-to-steel vulcanised inner pivot bushes on the lower control arms. These bushes are subject to progressive degradation from age hardening, ozone cracking, UV exposure, and the continuous compressive cycling loads imposed by the relatively heavy 6A13TT drivetrain. As the rubber compound hardens and fractures, the bushing loses its ability to control arm pivot geometry precisely, allowing fore-and-aft movement of the lower arm that shifts camber and caster dynamically during braking and cornering. NZ/AU imports of this generation are typically 20-28 years old at time of sale, making inner bush collapse nearly universal. Many examples have had aftermarket polyurethane bushes substituted, which can transmit significant NVH into the cabin if the incorrect hardness grade or inadequate grease is used during fitment.

  What you would notice

  • Clunking from front suspension over bumps, during braking or when pulling away
  • Vague, wandering or imprecise steering feel at highway speeds
  • Uneven tyre wear, particularly pronounced on the inner shoulder
  • Vehicle pulls to one side under firm braking
  • WOF failure on suspension play check

  Typically $350–$900 to put right.

• Costly issue

  Check power steering fluid reservoir level and colour — it should be clear or light pink, not dark brown or burnt-smelling.

  See why

  Power Steering Rack Internal Seal Weeping

  The hydraulic power steering rack on the Legnum EC5W develops internal seal weeping with age, causing slow fluid loss into the rack bellows or external weeping at the steering column seal. JDM imports commonly arrive with this fault undetected due to the slow leak rate. Continued low fluid operation damages the power steering pump and leads to pump bearing failure as a secondary failure.

  What you would notice

  • Power steering fluid level dropping without an obvious puddle on the ground
  • Fluid residue or wet appearance inside steering rack rubber bellows
  • Heavier steering feel especially when cold or at low speed
  • Whine from power steering pump at low speeds or on full lock

  Typically $400–$1,100 to put right.

What these repairs cost on other cars

Some of the Mitsubishi Legnum’s documented faults are repairs other models share. Each page lists the documented NZ cost for every model it affects.

• Cambelt Replacement Cost

Other Mitsubishi models