Mazda BT-50 Problems

This is, indeed, a known problem with Ford (and other) automatic transmissions. The layout of your transmission uses the engine’s coolant to cool the transmission by running a transmission fluid line through the radiator. And yes, when that line fails, the coolant mixes with the transmission fluid. That leads the transmission to fail mechanically (the coolant doesn’t lubricate the transmission) as well as the coolant destroying the transmission’s computer.

By insurance, I take it that you took out an extended mechanical insurance policy when you bought the car, because general car insurance won’t cover mechanical failures such as this. Given the get-out clauses with which some of these policies are riddled, I’m not surprised that you aren’t covered for the full cost of the repair.

Mazda increased its factory warranty to five years/unlimited kilometres in August 2018, but when your car was new, it was covered for only three years. I’d still be giving my Mazda dealer a call, though, as you might find the relatively low kilometres you’ve covered might convince them to make a pro-rata offer for part of the repair costs. I wouldn’t hold my breath, but it’s got to be worth a try. And, no, I don’t consider 98,000km to be a reasonable distance for a modern transmission to fail.

Many owners have changed from a dual-mass flywheel when changing the clutch in their utes, and none have reported a major vibration problem after the change. I would doubt it is the flywheel that’s the problem, look elsewhere in the driveline.

You can buy a steel tray for it, but that alone is unlikely to stop the back end from stepping out in slippery conditions. The old way of stopping this sort of thing happening was to put some load in the tray, some bags of concrete or sand will help, but you also have to drive it to the conditions.

I agree the head unit would be a logical thing to check. Mazda has a responsibility to fix the problem, so put the onus on them to come up with a solution, and keep the pressure on them until they do.

This is, indeed, a known problem with Ford (and other) automatic transmissions. The layout of your transmission uses the engine’s coolant to cool the transmission by running a transmission fluid line through the radiator. And yes, when that line fails, the coolant mixes with the transmission fluid. That leads the transmission to fail mechanically (the coolant doesn’t lubricate the transmission) as well as the coolant destroying the transmission’s computer.

By insurance, I take it that you took out an extended mechanical insurance policy when you bought the car, because general car insurance won’t cover mechanical failures such as this. Given the get-out clauses with which some of these policies are riddled, I’m not surprised that you aren’t covered for the full cost of the repair.

Mazda increased its factory warranty to five years/unlimited kilometres in August 2018, but when your car was new, it was covered for only three years. I’d still be giving my Mazda dealer a call, though, as you might find the relatively low kilometres you’ve covered might convince them to make a pro-rata offer for part of the repair costs. I wouldn’t hold my breath, but it’s got to be worth a try. And, no, I don’t consider 98,000km to be a reasonable distance for a modern transmission to fail.

Is it something new, or has it always been this way? I’m wondering if you’re just feeling the diesel engine, which works best at lower engine speeds. Rev it too high and you’ll lose the effect of the diesel torque. It could simply be that, or it could be an electronic problem. Have a mechanic run a diagnostic check on it to see if there is a problem.

There is a current recall affecting 30,505 MY 2016-2018 BT-50s. It relates to two front brake issues, one for a potential front brake hose failure, the other for possible front brake calliper cracking. Both could affect the car’s braking. To see if your BT-50 is one of those affected phone Mazda Customer Support (1800 034 411).

I’ve hard of this before and it usually seems the cause has something to do with the wiring that controls these warning lights. It could either be a bad earth or a broken wire, but in most cases the symptoms are the same; a flashing 4WD indicator light when the vehicle is in two-wheel-drive. I’ve also heard of dud ABS sensors triggering the same, or similar, warning lights on the dashboard.

These vehicles use servos to engage four-wheel-drive (unlike older vehicles which used a manual lever pulled on by the driver) so there’s a level of electronics involved. And that always means potential problems as the cars age, particularly a vehicle that may have seen its share of rough stuff over the years.

The best advice is to have a Mazda specialist interrogate the on-board computer, at which point the car should give up all its dirty little secrets, including why it thinks it’s in four-wheel-drive when it’s not.

You’ll almost certainly cause the dashboard to present you with a `check engine’ warning light, Brett, as blocking off the Exhaust Gas Recirculation (EGR) valve is an intrinsic part of the vehicle’s emission controls. Having the vehicle go into limp-home mode is a very real possibility as well.

But perhaps more financially damaging would be the consequences of being caught driving the vehicle with a blocked-off EGR. The government takes a very dim view of anybody disabling any part of a car’s emission controls and the fines for doing so can be huge.

However, I know this is a real issue for many owners of modern turbo-diesels. The problem is that soot from the exhaust gas is mixed with oily fumes from the crankcase and then ingested by the engine as part of keeping emissions down. But the mixture of oil and soot can form a black gunge that can block the intake system. Really, though, blocking the EGR is a fairly clumsy way of getting around this. My advice would be to fit an oil separator which should keep the oily mist from the crankcase ventilation out of the equation.

Opinions are divided on this subject, Steve, but there’s a school of thought that says you shouldn’t tow anything heavy in an overdrive gear. Manual-gearbox Toyota LandCruisers of the last 30 years or so are prime examples of this, and hauling a heavy load in fifth gear in these can destroy a gearbox real quick. But all vehicles will be better off with overdrive locked out while towing; it’s just kinder to the driveline. So, your decision to tow in fifth gear rather than sixth is a sound one.

The only catch with some vehicles is that both fifth and sixth gears are overdriven. But fifth gear in the BT-50’s automatic gearbox is not, it’s 1:1, so you should be fine as long as you don’t exceed the manufacturer’s towing limits at any stage.

As for putting bigger wheels and tyres on the BT-50, you’d actually be altering the gearing, making it taller, which means the vehicle may not cover ground as effortlessly as it does now. Hills and headwinds might require more throttle, too, and that will mean higher fuel consumption.