Mazda BT-50 Problems

It mightn’t seem like the vehicle is struggling, but when you consider that a caravan of this size can easily weight the best part of three tonnes, you can see how it puts a strain on every component of the vehicle towing it. It sometimes only takes a small hill or a headwind to push a towing vehicle into its discomfort zone. Do that long enough and eventually something will get hot enough to trigger the limp-home response.

But don’t rule out a check-up at a BT-50 or Ford Ranger (they’re the same vehicle under the skin) specialist who should be able to pinpoint the weak link, as well as offer solutions to stop it happening again. You might find you need a bigger transmission or engine oil cooler, or even a retune of the engine to bring it back to tip-top shape.

Accessories you’ve added can also make a difference. Have you, for instance, fitted a roof rack or larger wheels and tyres? A roof rack can add a lot of aero drag that has to be overcome, while bigger tyres can mess up the vehicle’s gearing, causing it to work harder for the same road speed as before.

A powertrain warning light can be triggered for literally hundreds of reasons. So there’s no point trying to guess what’s wrong here. Instead, have the vehicle electronically scanned at a workshop and see if the on-board computer can shed any light on what components or systems are at fault.

Theoretically, the computer should have logged the cause each time the warning light has flashed on. During a scan, these faults will show up as a series of fault codes which the mechanic will be able to decipher to get a good idea of what’s wrong. Without this information, you could be chasing up blind alleys for weeks and months.

The other thing you can do is make a note of what the vehicle is doing when the light comes on. For instance, if the warning light flicks on when you’re towing, you may have a driveline overheating issue.

Here’s the simple test. Does the vehicle have a body coloured front bumper-bar and chrome exterior door handles and mirrors? If it does, it’s an XTR. If not, it’s an XT.

There have, indeed, been issues with this transmission with Mazda authorising a service bulletin to attend to some vehicles. However, it‘s generally thought that affected vehicles were built between 2011 and 2014, after which point, the problems were fixed. Which is not to say your 2015-built car doesn’t have the same problems.

The best way to proceed is to ignore the dealerships and go straight to Mazda Australia’s customer service department. Unfortunately, your car is now 10-years-old and well and truly outside its warranty, but I agree that 120,000km is not an acceptable lifespan for a component such as a modern automatic transmission to fail.

The last decade of dual-cab four-wheel-drive utes have emerged as the tow-vehicles of choice, and you see them everywhere filling roles exactly like the one you have planned. Popular models include the Ford Ranger you’ve nominated, Toyota HiLux, Mazda BT-50, VW Amarok, Mitsubishi Triton, Nissan Navara and Isuzu D-Max. But there are also cheaper alternatives including makes like the South-Korean made Ssangyong and various Chinese brands like LDV and Great Wall.

Just make sure you know exactly how much you need to tow before making a decision as some of the cheaper models don’t have the same outright towing capacity and even if they do, some of them don’t have the engine performance to make towing as easy as it should be. For parts availability, the Toyota would be king in really remote areas, but any of the major brands are pretty well covered in Australia.

Meantime, don’t rule out ute-based wagons such as the Ford Everest, Isuzu MU-X, Mitsubishi Pajero Sport and Toyota Fortuna. These offer better ride comfort when unladen thanks to more sophisticated rear suspensions and most have as much or almost as much towing capacity as their ute brethren.

On the surface, you’d probably start looking at the car’s fuel system. A diesel, even a modern one, is controlled largely by how much fuel is being pumped into it and at what pressure. If the fuel pump is slack or the injectors, filters or lines are faulty or leaking, you might find that there’s simply not enough fuel to keep it revving on beyond that 2200rpm.

But you could also be looking at an exhaust problem, a partially blocked intake system, dirty air filter, or even a worn out turbocharger. A mechanic who is familiar with this make and model is going to have the best chance of diagnosing what’s wrong. Chances are yours is not the first vehicle to do this, and a specialist mechanic has possibly seen it all before.

The fact that the fuel economy average seems to be creeping up can have a lot to do with the fact that you’re becoming more familiar with the vehicle and using more throttle as a result. But remember, too, that until you reset the average on the trip computer, what you’re seeing is the full history of your consumption from when the trip computer was last zeroed, not just the most recent trip you’ve done.

It's true that engines often start to use a little less fuel as they 'bed in’ after a few thousand kilometres. And for a modern turbo-diesel like yours, I reckon 10,000km or even 15,000km might be the magic number. However, don’t be too disappointed if it doesn’t come down a whole lot. I reckon for that vehicle, driven the way you’ve described, 10 or 11 litres per 100km isn’t a bad average to aim for.

Other factors play a big part, too. Does the vehicle have a bull-bar or roof racks? Both these add weight and aerodynamic drag respectively, and can easily make the car consume more fuel. A roof rack at 100km/h can be worth an extra litre per 100km.

A lot of modern transmissions don’t have a dipstick at all, particularly as manufacturers move towards transmissions that have very long service intervals and are considered sealed systems. Which is fine until it’s not. And that’s when you need to check the level and condition of the transmission fluid.

The good news is that the BT-50 in question does have a dipstick. The bad news is that’s mighty difficult to get to. You need to be under the car (so safety is the key here) and then locate a 19mm fitting on the driver’s side of the transmission. By unscrewing this fitting, you can withdraw the dipstick and check the level. The other catch is that you need to do this with the engine running (to get an accurate reading) and the dipstick is located close to what will therefore be a hot exhaust system.

All of this means it’s really a job for a specialist with a hoist and is a great example of a carmaker saving a few cents per car in production at the expense of the greater running costs for the owner over the life of the vehicle.

A squeak when taking off from rest could be anything from a brake problem to a wheel bearing fault, a noisy engine drive-belt, bent axle, a dry suspension bush, worn universal joint or just about a hundred other things, including the driveshaft you already suspect.

Of potentially greater concern is the cut-off exhaust system or, more correctly, the previous owner. Anybody who cuts up an exhaust to make more noise is also a likely candidate to have driven the vehicle hard. It might be better to find a vehicle that hasn’t been messed with and potentially abused.

A sawn-off exhaust system shouldn’t harm the turbocharger or engine, but it can make a difference to performance due to reduced back-pressure. It also makes me wonder what else has been changed of fiddled with in the name of more power. Sometimes the performance will actually be improved, but you also open a can of legal and insurance worms by changing things like factory exhaust systems in what is a fairly agricultural way.

The smart money here suggests that there’s something your car’s electrical system and body computer don’t like about replacement LED lights. That’s assuming you’ve installed them correctly, of course. The first thing you should do is replace the standard globes and see if that restores the lights’ operation. If it does, you can be reasonably sure there’s a problem with the way the car reacts to the LED replacements.

Not all cars appreciate the conversion to LEDs. These newer lights draw a lot less current than conventional globes and, while that sounds like a good thing, the lack of current-draw detected by the body computer can cause problems. Another common problem with LEDs is that the low current-draw makes the car’s computer think that there’s a blown globe at which point it can trigger a warning light on the dashboard.