Mazda BT-50 Problems

We have seen a number of reports of the tub cracking on the BT-50 and the Ford Ranger, but we haven't had any reports from owners ourselves. Take a close look at the design of the ARB canopy and then get your Mazda dealer to show you what Mazda does on its approved canopy to avoid the tub cracking issue. Also check to see who actually makes the Mazda canopy, it's likely to be one of the local manufacturers anyway.

As Mazda pointed out to you the fuel consumption figures they publish are the results of laboratory tests mandated by the government. Every carmaker has to do the test and publish the results on a sticker on the windscreen of the car. As such it shouldn't be taken as fact that you will get the same figures when you drive the car in real life. The figures are given as a guide and for you to use when comparing one vehicle with another. There are many things that affect fuel economy, so you need to check everything that might cause your consumption to be higher and make sure you are doing everything you can in your driving environment to minimize your fuel consumption. Having done all of that it does seem that your vehicle is using too much fuel, as you say. I would engage your dealer and ask that he set up a fuel consumption test that measures the actual amount of fuel you are using so that both you and the dealer are in agreement about the fuel being used. You will then have a common basis on which to discuss what action you and the dealer could take going forward.

It could be the diesel particulate filter alerting you that it's doing its thing. DPFs regularly go through a regeneration process, and most do it while you're driving along without any real impact on the performance of the car.

It is a relatively common complaint with the BT-50 when towing and we get quite a lot of complaints from Navara owners as well. The answer seems to be that the clutches fitted at the factory are marginal for heavy-duty use, and the answer from mechanics we've spoken to is to fit heavy-duty aftermarket clutches.

There are a number of heavy trucks running dual-fuel systems with a blend of diesel and natural gas, on some the gas is compressed (CNG) and on others it's liquefied (LNG). There are also other heavy truck systems that use diesel and LPG. We have reported on all of them over the past couple of years. In the case of light commercial vehicles the systems employed use diesel and LPG, substituting LPG for diesel, and as you say it needs to be very carefully controlled. The more LPG you use the more power you will get, but if it's not well controlled you run the risk of damaging the engine and that's very costly.

Mazda tell us they have come across cam belt failures on the BT-50, but that it wasn't what they would refer to as a common concern, and not one they consider to have an abnormal rate of failure. From that you could deduce that it's not an unusual failure, but the failure rate isn't sufficiently high to do anything about.

Jumping out of fifth gear is a common problem on early BT50s, but a fix was supposed to have been introduced in late 2007. I agree that Mazda should bear at least some of the cost of the repairs so take it to a Mazda dealer and submit a claim.

A lot of the new generation of common-rail diesels rattle cold, no matter the brand. They all use the same fuel-injectors, which appear to be the cause of the problem, and there doesn't appear there's much that can be done about it.

I would urge caution. These systems work by substituting a percentage of the diesel fuel with LPG and do deliver more power or better fuel economy depending on how you drive the car. The general idea is that you don't have to depress the throttle as far to get the same performance and you can then realize some fuel consumption savings, but I have had quite a number of reports of serious engine meltdowns because the driver simply couldn't resist the temptation to keep the foot down on the throttle. My concern is also that there isn't the same experience with these systems as there is with dual-fuel systems on petrol engines, so they're more exposed to problems. Before you do it talk to other owners about their experience with the systems.

We haven't heard of belt failures like you report, but it would be good to hear from any of our readers who have suffered the problem. It sounds like a serious one.