How good are your ute's brakes?

The difference between a collision and a near miss can come down to how good your brakes are, yet most popular mid-size utes continue to employ rear drum brakes – a braking design once used by most cars but known to offer less efficient stopping power than discs.

The release today of carsales' Best Dual-Cab 4x4 Ute 2022 once again highlights how most of the leading utes in Australia use rear drums rather than better-performing rear disc brakes, including new-generation models released in the past couple of years.

From the seven contenders in our latest ute mega-test, only the new Ford Ranger and the GWM Ute are fitted with four-wheel disc brakes.

That leaves the Isuzu D-MAX, Mazda BT-50, Mitsubishi Triton, Nissan Navara and the top-selling Toyota HiLux with rear drum brakes only. The previous Ford Ranger only offered rear disc brakes on the high-performance Raptor.

Given the long model lifecycles involved with light commercials such as these, it could be many years before the nation's most popular vehicles are fitted with higher-performing rear disc brakes.

It also flies in the face of many of these utes now adopting the latest safety technologies, with all of the models on Best Dual-Cab 4x4 Ute offering autonomous emergency braking (AEB), forward collision warning (FCW), lane keeping assist (LKA) and lane departure warning (LDW), for example.

Of the other volume-selling utes, only the Toyota LandCruiser 79 and Volkswagen Amarok use rear discs. Even the much lower volume – and cheaper – players in the market, such as the LDV T60 and SsangYong Musso, run rear disc brakes.

Disc brakes dissipate heat and therefore resist brake fade better than drum brakes.

Being exposed to surrounding ambient air, disc brake rotors and pads can more easily shed heat created by braking, whereas drum brakes contain much of the heat created within the drum assembly.

In the opposite situation – when the brakes have been immersed in water, such as an off-road water crossing – drums take much longer to dry out than discs and are far less effective until they have done so.

Drums also pick up mud and grit more easily (in off-road or mining applications, for example) and this can damage the internal hardware.

Almost all vehicles from small cars to SUVs are fitted with rear disc brakes. Rear drum brakes only dominate two popular classes in the car industry: micro-cars and utes.

Such a brake design being popular in a class where vehicles are low-mass city runabouts is one thing, but to have them on vehicles that weigh two tonnes or more, can carry a further tonne of payload and tow up to 3500kg, is another – even if the drums are much bigger on utes than micro-cars.

In carsales’ own testing of unladen dual-cab 4x4 utes performing an emergency stop from 60km/h, all achieved a similar result – whether drum or disc braked.

This data and other reports suggest that for daily family duties in the suburbs, an unladen rear drum-braked ute would not need much if any more real estate in which to make an emergency stop than a rear disc-braked ute.

However, as aftermarket suspension firm Pedders has found, braking distance increases considerably when performing an emergency stop at speed in a laden ute equipped with rear drum brakes.

While Pedders has a vested interest (with its ute disc brake conversion kits), independent testing it commissioned showed a 21.4-metre reduction in braking distance with a fully laden Toyota HiLux fitted with a Pedders rear disc-brake kit compared to standard, rear drum-braked HiLux when fully laden.

Pedders brake director Steve Altair says rear discs are generally better than drum brakes because of “their improved heat dissipation, shorter stopping distance, less pedal effort and they’re better for maintenance”.

Many manufacturers still fit drum brakes to utes because drum brakes are simpler and cheaper to make.

Rear discs brakes are more complex because manufacturers have to incorporate a parking brake (either mechanical/electrical activation of the disc brake calliper, drum-in-disc type or a driveline drum brake) and can require an uprated master cylinder/brake booster.

That doesn’t mean it’s inordinately expensive to build a ute with rear discs, as evidenced by the utes mentioned above and the host of mechanically-similar, ute-based 4x4 wagons such as the new Ford Everest, Isuzu MU-X, Mitsubishi Pajero Sport and Toyota Fortuner, all of which come with rear discs – and they're ventilated, too.

Rear brakes may only contribute about 30 per cent of braking force in an unladen vehicle, in which the front brakes take on most of the work.

Yet 30 per cent is not insignificant; even if it only contributes to a metre or two shorter stopping distance, it could make the difference between a collision or not.

Amplify this in a high-speed emergency braking scenario with a heavily laden ute, a heavy trailer or simply negotiating a long steep descent, then losing much of that 30 per cent because of brake fade could be critical.