Isuzu Problems

Isuzu lifted the warranty on its vehicles to six years/150,000km for all utes sold after May 1, 2019. Unfortunately, it sounds like your car was on the road in 2018, which means it was covered by a five-year/130,000km warranty. Although you haven’t yet covered 130,000km, the vehicle is more than those five years old so, technically, the problem is not covered by warranty.

However, I think it would be worthwhile contacting Isuzu Australia’s customer service division and pointing out the car’s service history and its mileage. Isuzu may then decide to help with the cost of repairs on a pro-rata basis given the circumstances. It is not obliged to, of course, but it’s definitely worth asking.

You’ve kind of already answered your own question by saying that you’ve already waited a year for delivery. Saying no to this one and ordering another might see a similar delay and you’d be back to square one. And a year older. Like many brands, Isuzu deliveries were adversely affected by global supply-chain problems and the world shortage of silicon-chips needed to make on-board computers work.

There are two issues with a car with last year’s build date. The first of these is that the motor trade uses the year of manufacture when calculating retained (trade-in) value. So, if you don’t plan to keep the car long before trading it in, then maybe that’s a concern. If you plan to keep it for 10 years or so, then an extra birthday will have very little affect on its trade-in value by then. This is something you might be able to negotiate on with the dealership you’ve purchased from

As for warranty, Australian Consumer Law states that motor vehicle warranties start form the date of first registration, not the build date. So even though the car might technically be six months old when you get it, the factory six-year/150,000km warranty will start from the day it’s delivered to you as a brand-new vehicle. The exception to this is if the car was originally a dealer demonstrator, when the warranty would start form the time it was registered by the dealership. If that’s the case, this should be reflected in the purchase price as it’s no longer a brand-new car you’re buying.

Sandy conditions are incredibly hard on every aspect of a four-wheel-drive. The sand itself constantly shifts under the tyres and clings to them as well, dragging them down and making the engine and transmission work very hard to maintain progress. You may have already noticed that you use a lot more fuel in sandy country and it’s all because you need to be constantly making more power to maintain speed than in normal conditions. Turbocharged engines and automatic transmissions, in particular, can get very hot very quickly in sand.

With that in mind, it’s very possible that something in the driveline got hot enough for the car’s computer to go into limp home mode to protect what ever was hot from damage. Limp home mode often involves limiting engine revs and turbo boost, both of which contribute to heat production. This would explain why the car would not climb a crest but came good after a break.

It's true that new engines can be 'tight' and this can lead to higher fuel consumption than they achieve with a few more miles on board. And since you're almost at the 30,000km mark now, why not try the dealer's advice and see if things start to improve.

The MU-X was never the most fuel efficient vehicle in its class, but even so, 12.2 litres per 100km on the highway sounds a little excessive (although not as much as you might think). I'd expect this vehicle to return highway fuel economy figures closer to 10 litres per 100km or maybe a bit less.

However, there are several factors that might be skewing your results. The bluff aerodynamics of a vehicle like the MU-X mean that even a slight headwind can increase consumption. So can the addition of accessories such as a bull-bar and roof racks. A set of roof racks on their own can add a litre of fuel to every 100km travelled, and that's if they're not loaded. Throw a spare tyre and some gear up there and it's even worse.

Bigger (taller) tyres can also increase fuel consumption, and so can running your tyres at too low a pressure.

This needs to be sorted out quickly as a car that you can't be sure is in Park is always a potential to roll away on its own causing who knows what grief and damage. It sounds like there's something amiss with the way the gear selector is talking to the actual transmission, and any resistance in the action of the shifter really shouldn't be there. That said, you do need to have your foot on the brake to select a gear from Park, so maybe you're taking your foot off the brake pedal prematurely.

You're possibly correct that the two issues are related as a car that thinks it's not in Park, will probably not want to allow you to use the walk-away locking mode. But here's the good news: This is absolutely a warranty issue and Isuzu needs to fix it at its cost.

Book the car in to be inspected as soon as possible and, in the meantime, make sure it's parked somewhere from which it can't roll away. Physically chocking a wheel (with a house-brick, a rock or whatever) isn't a bad idea till it's fixed, either.

This sounds like a case of low transmission fluid. Check the transmission dipstick according to the instructions in the owner's manual to see if the level is where it should be. Low fluid level can cause all sort of problems from slipping to a lack of drive to uneven shifts and shifts occurring when they shouldn't. Also, try to find out what fluid was put in the transmission when it was last serviced. The wrong type or grade of fluid can cause the same types of problems as not enough fluid.

If the fluid checks out, then you need to start looking at other causes such as glitches in the on-board computer that controls the driveline. An electronic scan of the vehicle would be the next step.

It sounds very much like the transmission is confused electronically or has a problem with its valve body which is supposed – in conjunction with the computer – to make decisions about what gear the transmission should be in. Perhaps it's as simple as a dodgy electrical connection somewhere and the impact of potholes or buffeting from passing trucks is causing a short-circuit somewhere.

The first piece of advice, however, is to not drive the vehicle any farther. You not only risk damaging the transmission, but it's also dangerous to drive a vehicle that might suddenly select the wrong gear at random. The second piece of advice would be to take the vehicle to a dealership and have its computer scanned to see if any fault codes have been recorded. If your local dealer doesn't want to know, take it straight to head office and contact Isuzu's customer service division.

The good news is that your vehicle is still under the factory warranty, so make it Isuzu's problem, not yours. Just make sure that the behaviour has been logged as a problem, at which point it's classed as a pre-existing condition and Isuzu is still obliged to fix it even if the warranty runs out.

A bit of sweating around the various parts of an engine where one component joins another is definitely not uncommon and not really a problem provided it's not actually dropping oil on the ground (at which point it's a leak, not a sweat-mark). But really, an almost-new vehicle like yours shouldn't be doing this at all.

The rear-main seal on the crankshaft is a likely culprit and a common source of leaks from this area, but since it's a big job (gearbox removal) to do it, I can understand why a mechanic would declare it okay and not to worry. The problem with that is that the sweating is likely to become a leak sometime down the track, at which point you'll have to act.

The good news is that because you've flagged this problem with Isuzu while the vehicle is still under warranty, it's called a pre-existing condition and is covered by the factory warranty, even if that warranty has since expired. However, one would hope that Isuzu does the right thing in the meantime and changes the offending gasket or seal to fix the problem.

Be very wary, however, about Isuzu (or more likely the dealer) claiming the problem is being caused by the catch-can you have had fitted. A good quality catch-can, with a relief valve and correct installation should not cause a rear main seal to leak. As for changing the grade of oil you're using, I doubt that it would do much, but since the alternative is a slightly thicker oil, it might just make the difference you're chasing.

Problems like these are hard to diagnose remotely, as there's a lot going on in a modern gearbox. But, conventional wisdom suggests that a noise followed by a series of failures of the same component (the oil seal) means something inside is bent or damaged.

The noise is potentially being caused by something misaligned and rubbing or a damaged bearing, and the blown oil seal is the eventual result of the damage/swarf/heat/friction that results. The other possibility is that the rear gearbox seal is being destroyed from the other end of things, as in the tailshaft. A bent tailshaft could set up harmonics, friction or vibrations that could kill the seal, but you'd imagine there'd be a vibration through the whole vehicle at speed if this was the case.

Your vehicle is under warranty (six years of it from new) so make sure the dealer is aware of the problem and their obligation to fix it.

It doesn't matter whether it's a common fault with this make and model, because the reality is that the vehicle is still under the factory warranty, so it's Isuzu's problem, not yours.

Provided, that is, that the fault occurred on its own and not as the result of an impact that would be deemed accidental damage.

Generally speaking, these LED information screens and other touch screens are pretty reliable and robust, but problems have been known to occur including loss of touch control and the sort of crazing you're noted. Isuzu is not alone either, and many brands have similar issues. The crazing can also be the result of temperature extremes (hot and cold) and will sometimes go away when the ambient temperature returns to a more moderate level.

The type of problem can often be fixed by replacing the actual screen (or in this case, rotary dial) rather than the entire control unit. But it's a specialist job and involves dismantling at least some of the dashboard to achieve.