Mitsubishi Triton Engine Problems

The 2.5-litre turbo-diesel engine fitted to the 2010 Triton uses a toothed rubber timing-belt which requires periodic replacement. Most mechanics reckon the belt should be changed every 100,000km and because of the design of the engine, the belt that drives the engine’s balance shafts should also be replaced at the same time.

The MQ Triton doesn’t seem any better or worse than its rivals in this department. But, like other makes and models, there’s a healthy aftermarket supply of replacement intercoolers and the pipework that feeds them, so it’s definitely not an unknown problem.

But your experience is exceptional. Were all five vehicles bought brand-new at the same time? If so, they’re all likely to be from the same production run which could explain a faulty batch of hoses.

You don’t tell us why your ute needs a new head at just 134,000 km, so it’s hard to comment. If nothing untoward has happened to cause the problem, like overheating, then you could try and convince Mitsubishi to cover the cost of repairs, but unless you have a full history that clearly points to a manufacturing fault I think you would struggle to justify a claim.

Mitsubishi quotes a combined average of 10.9 L/100 km for the 2.4-litre dual-cab Triton. Around town they claim 13.9 L/100 km and on the highway 9.1 L/100 km. It’s similar to other dual-cab utes.

From what we can see, that specific Triton carried an official combined fuel consumption figure of 10.9L/100km. 

In the real world, you can expect to achieve a similar number on a constant highway cruise, but be prepared for it to climb to something more like 15L/100km around town. So more like a six cylinder modern Falcon or Commodore than a Corolla or Mazda3. 

By how far did you miss the service? Was it by a 1000 kilometres or so, or did you miss it all together? If you missed the service by a few weeks or a few kilometres then I would not expect the engine to seize, but if you skipped the service completely I’m not surprised. I’m also guessing the warranty won’t be honoured because of the missed service, but depending on the circumstances surrounding the missed service you could try and negotiate with Mitsubishi for some cover.

You’re going to be hard-pressed to show that the problem was either a design or manufacturing problem, as it’s unlikely to be either. Even though the wiring loom just sits and doesn’t appear to be subjected to any stress it being subjected to all the bumps, vibrations and whatever else is happening through the vehicle in general. It could be a faulty connection; it could be any number of things. Pay up and get on with your retirement.

Check the warranty document, which should tell you what is specifically not covered. Normally it’s the consumables that are not covered, that’s things like oil filters, air cleaners, spark plugs, belts, brakes and clutches. Fuel injectors don’t normally fall into the consumable category.

The claimed average for the Triton diesel is 9.6 L/100 km, the claimed consumption for urban driving is 11.9 L/100 km, for highway/country driving it’s 8.3 L/100 km. That, of course, is the result of a laboratory test, not a real world one, so you have to allow for some variation.

You also have to allow for some variation due to loading, driving style, road conditions, tyres and the general state of the car. I’d recommend that you keep accurate records of the fuel used so you have the data to present to the dealer, and to Mitsubishi. If your data shows the car is not performing as they claim it should ask them to rectify it. Should they refuse approach the consumer affairs people with a claim that the vehicle as supplied to you is not what was represented to you.

If the suction control valve is worn or there is contamination present the fuel pressure will be affected and so will the drivability as a consequence. The car will sometimes go into limp home mode when this happens. It is a relatively common complaint on common-rail diesels, and the only thing to do is to replace the valve.