Car Advice

Toyota Fortuner and Toyota HiLux technical analysis – 4WD systems explained

20 Feb 2017

Robert Pepper 6

Every new 4WD has its own particular off-road system. Here’s how the 4WD systems on the Toyota Fortuner and Toyota HiLux works…

THE FORTUNER is essentially the same vehicle as the HiLux, but with a shorter wheelbase, wagon body and coil springs intead of leaves. The electronic and 4WD systems are the same, and although calibrated differently due to the different vehicle characterstics, work the same way from the driver’s perspective. This article refers to Fortuner – where the HiLux is different that will be mentioned.

What’s it got?

The Fortuner is a part-time 4WD vehicle which means you have to run it in 2WD on the road, only using 4WD on loose-traction surfaces like dirt, sand and mud. The Fortuner also has a variety of electronic driving aids, which are:

• VSC – Vehicle Stability Control, better known as ESC or Electronic Stability Control. That’s fully explained here.
• DAC – Downhill Assist Control, otherwise known as HDC or Hill Descent Control. That’s a system which permits very slow speed, steep hill descents by braking individual wheels. Operates under 30km/h, and only in 4WD high or low range, and with the rear differential lock disabled. The Fortuner GX model does not have DAC, and only automatic HiLuxes have it.
• TSC – Trailer Stability Control. A subset of VSC, detects and corrects/prevents trailer sway by braking individual front wheels. Very much worth it.
• TRC – Traction Control (Engine). Cuts the engine power to prevent wheelspin. Otherwise known as engine traction control (more on that here).
• A-TRC – Active Traction Control (Brake Traction Control). Detects wheelspin, brakes individual wheels so the car can move forwards.
• Rear cross-axle differential lock – Disables all electronics when it is activated, and can only be used in low range.

In 2WD mode the Fortuner has all its electronic aids active. Only use 2WD on high-traction surfaces, including wet bitumen.     In 4WD high mode all aids are active, although VSC appears to be detuned to permit more slip to the point where it doesn’t really interfere with most offroad situations.   In low range TRC is disabled (but A-TRC remains enabled), and VSC is entirely disabled.  A long press (three seconds) of the VSC button when in low range will disable A-TRC as well. A long press has no effect if not in low range.    

What do I use, when and how?

For normal onroad driving you must have the Fortuner in 2WD. You can disable VSC and TRC at low speeds only with a single VSC button press, but they re-enable above about 50km/h. There’s really no point disabling them as they step in if you have done something very wrong. They come in very progressively and the electronics are a wonderful safety net.   On dirt roads the Fortuner, like any part-time 4WD, is best run in 4WD high for traction, stability, less tyre wear and less damage to the road. There is no fuel consumption penalty noticeable without resorting to lab equipment. VSC, TRC and A-TRC remain enabled but again if they kick in, it’s because they need to, so you should just leave them enabled.     Offroad — in slow-going terrain like rocks and ruts just slot it into low range. VSC will disable, as will TRC, and A-TRC will remain active. Do not disable A-TRC by pressing the VSC button; it is your friend.   For terrain where you can move faster and use high range, like sand and perhaps snow, then most of the time simply selecting high range 4WD is all you want. This gives you 4WD, A-TRC and to some small degree of VSC and TRC.   If the situation looks like you need unrestricted power in high range with no computer control — as would often be the case in sand — then disable VSC and TRC with a long press of the VSC button, but be aware you’ve now lost A-TRC which will help in situations such as climbing straight up a rutted sand dune. A short press only disables TRC and then only below 50km/h. Toyota seems to think this helps in the event of the car being stuck… I disagree; I think it’s a completely pointless mode.   The rear differential lock has its place, but not very often as A-TRC is so effective and works across all four wheels. The rear locker is best used in extremely rutted, high traction terrain such as very slow, rocky climbs.  It is also useful to engage on descents as it helps engine braking on the rear axle, although models above the GX have DAC… and you can’t have DAC and the rear locker engaged. It is good the rear locker exists, but do not assume the Fortuner is more capable with it in than with it out. Only automatic HiLuxes get DAC.   Finally the Fortuner has a trick up its sleeve with its anti-stall technology, like all modern manuals. Just slot the car into first low, take your feet off the pedals and let it walk up the hill or whatever is in front. It will run out of traction before it runs out of torque. This also works pretty well in second low.   Read more in our Fortuner onroad and offroad review.