By Francois Rossouw
I often hear tales about car salesmen who have convinced the customer that an automatic SUV will be able to go where the 4x4s go, “because it is automatic and does not havea clutch that can burn out”. Such salesmen are uninformedand could cost you a lot of money! When your vehicle gets intoa slow or sandy situation, the torque converter has to work so hard to compensate for the lack of a lower gear that the gearbox oil will overheat very quickly.In certain new models and most older ones, there is no warning light to tell you when the gearbox oil is overheating, and this can cause a lot of damage. The overheating can cause the gearbox to burn out or an oil pipe to burst. In most cases when an oil pipe bursts and the oil runs out before you shut off the engine, the gearbox oil pump will seize, and as a result the gearbox will have to be overhauled.
No matter what the salesman says, an SUV without low range is not a proper 4×4, and usually it does not have sufficient ground clearance for off-roading in any case.If you cannot afford the vehicle you need, rather buy a second- hand one designed for the job than try to make the one youcan afford do work it was not designed for.There are some newer model 4×4 vehicles, such as the Volkswagen Amarok auto, that do not have low range. What they do have is an eight-speed automatic gearbox with the first two gears so low that they can work as low range.This same overheating problem arises when the driver of a proper 4×4 does not use low range.Some time ago we were in loose sand on the West Coast when Cristo Alberts’ Land Rover Discovery diesel auto started having problems. The vehicle had enough power to push itself through the loose sand, but the torque converter was slipping all the way.When I advised him to change to low range, he told me that he was a Land Rover salesman and knew the vehicle better than I did.
Needless to say, about one kilometre farther on the main oil pump to the oil cooler burst and oil was sprayed all over the engine, causing so much smoke that people in the group thought the Disco was on fire.We had to tow him to the next town, where Land Rover had to collect and repair the Disco.
This was not a vehicle problem. It was an error by a stubborn driver.I always say that if you are in Matric, do not try to write the exam with a Standard 6 mentality. This 4×4 had all the tools and the owner should have used them. On 4×4 expeditions, I often get called on the radio for help when a gear oil warning light comes on. After the driver changes to low range, the light goes off within a kilometre.With more and more automatic vehicles being sold, we need to know how they work. Automatic 4×4 is the way we
will all go eventually, because it makes 4×4 driving so much easier and less stressful.
Some 4×4 vehicles have a safety system through which the computer cuts the engine when the gear oil overheats, making it impossible to restart the engine. Most vehicle handbooks will tell you that it will reset within 24 hours, which could be very inconvenient. But if you loosen the battery terminals and wait for 20 minutes before you connect them again, the computer resets in most cases. Once you have restarted, immediately switch to low range where the gear ratio is lower and the torque converter does not have to work so hard.What would help most, however, is to have all 4×4 salesmen properly trained, so that they can explain these things to their customers and sell the appropriate vehicle to the appropriate buyer.