Mazda BT-50 Problems

First things first: are you sure the leak is coming from the gearbox and not the engine? It can be very hard to discern the difference in a manual car, although it’s easier in an automatic as the transmission fluid is usually a red colour.

Beyond that, oil can escape from a gearbox through a variety of places. The breather could be allowing fluid out, the pan seal could be leaking, the rear gearbox seal could be faulty or you could even have a cracked transmission casing. Don’t rule out a leaking drain plug, either, as this is a very common source of a leak. You might even find the leak is coming from somewhere within the transmission cooler and its plumbing.

Modern cars absolutely hate having low battery voltage. It throws everything into chaos and can easily produce the sort of problems you’re having as the major components of a car are, these days, all controlled by computers.

By turning the car off and on again, you’re effectively performing the old Alt-Ctrl-Del function to reboot a home computer or laptop. As such, and especially since the transmission works perfectly when you reset it, this is almost certainly an electrical problem. A more permanent reset might be needed, so try leaving the battery disconnected overnight and then reconnect it next morning. This will often return things to normal.

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.

This sounds more like a gearbox that isn’t selecting fifth gear properly, rather than one where it’s leaping out of fifth. For it to pop out of gear when cruising along suggests it’s not getting into gear fully in the first place. You might be able to adjust the shifter’s position and alignment and therefore get fifth gear to engage more fully.

There’s also a chance that this refusal to select fifth gear is the result of bent or worn selector forks within the transmission itself, and that’s a gearbox-out job unfortunately. So the first step is to get underneath with a torch while somebody inside attempts to select fifth gear. If the selector linkage runs out of range of motion, you might just have an adjustment problem which can be pretty easily sorted.

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.

It’s a bit hard to know what’s going on here. If a tyre is scrubbing on its inside edge, it’s often a problem with the camber settings (the amount of lean on the tyre from top to bottom). If it was realigned incorrectly, it’s conceivable that too much camber was removed and now the opposite problem is occurring where the outside edge is wearing too quickly. That said, sometimes incorrect toe-in and toe-out settings can cause similarly odd tyre wear.

Either way, this sort of problem should not be beyond the skills of a wheel alignment specialist to rectify without any mechanical changes to the vehicle or its suspension. In extreme cases, adjustable suspension bushes or mounting points can be fitted in place of the standard items to provide a greater range of adjustment. You may find that rectification is warranty issue, but if the misalignment came about through wear and tear or hitting a pothole or big bump, then it may not be covered by the factory warranty. Previous crash damage that has not ben repaired properly is also another common cause of weird tyre wear due to poor wheel alignment.

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.

You might be looking at two distinct issues here. The high idle could be caused by any number of things including a dirty intake system, or something electronic. It could simply be that the idle was set too high the last time the vehicle was serviced.

This may be contributing to the feeling of the engine shuddering when you switch it off, but in reality, a lot of diesel engines exhibit this. It’s all to do with the heavy-duty nature of the diesel engine design. Because of the high combustion chamber pressures inherent in the diesel’s design, the whole thing needs to be more physically robust than a petrol engine of the same size and capacity. That means everything from the crankshaft to the con-rods, pistons and even the cylinder head and crankcase need to be made stronger. And that means more material and that means more mass.

This is why diesels generally don’t rev as high as petrol engines (there’s much more reciprocating mass) and why they can feel a bit lumpy when you load them up and even at idle. So, when you switch one off, it can feel like it’s trying to jump out of the engine bay. However, if this sensation has become more pronounced over the years, it might be wise to check the engine and transmission mounts for wear. Any wear or looseness here can contribute massively to vibrations from the driveline being passed through to the cabin.

I’d start by talking to a transmission specialist. There’s a fair chance they will have seen these exact symptoms before in this make and model and will know what’s wrong without wasting any time or money on guesswork. It’s probably also worth going back to basics and checking the transmission fluid level, as low fluid can cause all sorts of drive problems. If, on the other hand, the gearbox is worn out internally, you’ll either need to rebuild or replace it, but don’t rule out something less expensive like an internal selector fault or even a torque converter problem.