Although the main objective of the Road Safety Foundation’s truck visibility project held on October 7th at Tugela Plaza on the N3 was to ascertain the state of lighting and other visibility components on trucks, FleetWatch took along our trailer expert, Wolfgang Lehmann, to check out braking on the trucks. Here too, the results were not good writes Patrick O’Leary.
While the cops from KZN and the team from N3TC and the Road Safety Foundation were looking at lights, FleetWatch’s resident trailer expert, Wolfgang Lehmann, was crawling underneath the trucks examining potential signs of braking faults. Due to there not being a pit where one could get under the truck and examine things in detail, the main inspections were limited to my good friend’s ability to bend his body just that little bit more than the ideal 90° angle between a slack adjuster lever and its push rod when the brake is applied.
In other words, apart from the occasional spurt of energy when he crawled right under the trucks and had to be hauled out by force, his inspections mainly centered around slack adjuster settings and brake boosters. Once again, we were amazed at the number of incorrect settings on the trailers inspected. “I estimate that 70% of the trailers I checked had the wrong brake settings. On many of the trucks, the brake boosters were mixed-up on the same axle (a long stroke booster on one side and short stroke on the other side) or bigger boosters were fitted to the front axle – which can lead to jack-knifing.
“Even more critical is the fact that mechanics don’t seem to have a clue about the push rod connection hole in the slack adjuster. They just connect the rod to any hole without taking into account the instructions on the Load Sensing Data plate – if, of course, there is a data plate affixed to the trailers as the law requires,’ says Lehmann.
Because of the absence of a pit, the load sensing valve/axle connections could not be checked but based on past experience, you can be sure that there would have been some which were disconnected.
All in all, Lehmann’s observations once again tell us that not nearly enough attention is being paid by mechanics to the correct brake settings on trailers.