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.

My take on it is that dealers should stop telling lies to their customers. Take your problem straight to Mazda Australia’s customer service division and side-step what is clearly a smoke-screen from your dealer. It is ridiculous to suggest that a relatively new vehicle needs ten seconds to engage a gear after it’s been sitting for a few days.

As for the problem itself, start with the basics. Check for a blocked filter in the transmission (which can slow down the flow of fluid) and make sure that the fluid itself is not just the correct grade and type, but also the proper brand. These modern transmissions are complex and intricate, and even something as simple as the incorrect fluid can create chaos. Beyond those simple fixes, the problem could also be caused by a few other faults. For starters, it could be an accumulator inside the transmission that is failing. The accumulator’s job is to store some hydraulic pressure (created by the transmission’s pump) so that the transmission always has enough pressure and fluid volume available to effect gearshifts. If this accumulator is bleeding off pressure when the car sits, it will need time to refill (again, from the pump) before the unit will be able to select Drive. The other possibility is that the pump itself is slacking off and taking too long to build up pressure within the gearbox. You could also be looking at a pressure valve that has lost the plot and supplying the part of the gearbox it’s responsible for with an incorrect line pressure. Either way, a gearbox that is slow to select gears is often headed for the scrap-bin.

Given that it’s possibly a fairly major problem, it isn’t going to get any better. Your problem is that Mazda didn’t introduce its five-year warranty until August 1, 2018, and vehicles sold before that date were covered only for three years. That said, you’re BT-50 might squeak in, particularly if you pointed this problem out to the dealer some time ago (within the first three years). At that point, it’s a pre-existing condition, and it will be covered by the factory warranty as it occurred within the warranty period, even if the dealer – as it appears in this case – elected to spin you a yarn and do nothing about it.

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.