If you're in Kenya, you've probably witnessed an empty plastic water bottle strategically tied to the wheels of long-distance trucks. While this may look random, there is actually a science behind it.
As it turns out, truck drivers, particularly those operating in Kenya and the East African region, tend to lift or suspend some of the trailer axles - a practice that goes a long way in saving fuel since it reduces rolling resistance because fewer wheels are in contact with the road.
Further, some trailers can have up to six axles, whilst not all of them are needed to transport goods, prompting drivers to lift them, which helps them manoeuvre the long vehicles easily.
Empty plastic bottles come in handy when it comes to monitoring the axles that are lifted while driving. With a bottle tied to the tyre's wheel nuts, a truck driver can easily determine whether an axle is off the ground through the side mirror. If the bottle is spinning, the driver will obviously conclude that the axle is in on the ground.
This practice is common not only in Kenya but also among regional and cross-border drivers transporting goods from Mombasa to countries like Uganda, Rwanda, and the DRC.
While it is extremely efficient in saving on fuel, the lifting of axles can easily lead to overloading since more weight is likely to be concentrated on the wheels in contact with the ground. The Kenya National Highways Authority (KeNHA) is wary of this fact, and this is why lifting axles can carry hefty penalties for drivers found engaging in the practice.
Notably, all wheels of the truck need to be in contact with the ground at weighbridges to evenly distribute the weight across the truck.
This is also where the plastic bottles come in handy for truck drivers, as they are able to ensure all axles are in contact with the road as they approach a weighbridge.
Some truck drivers have reported having seen their colleagues being subjected to fines of up to Ksh400,000 after they were nabbed driving vehicles with elevated axles. In extreme cases, drivers can also be subjected to jail terms.
Under the East African Community Vehicle Load Control Regulations, truck drivers found to have exceeded the weight limits can be slapped with a fine of up to Ksh40 million.
Section 17(6) of the Traffic Act stipulates that overloaded trucks can be held for three days without charge. After that, the owner is charged Ksh6,450 (about 50 USD) for each extra day the vehicle is detained.
Despite all these risks, truck drivers continue to elevate their axles, with some claiming it helps them navigate rough roads. The practice has been made more rampant by modern trucks, which have self-steering or tag axles that are designed to allow lifting when the trucks are not carrying maximum loads.
