While grease is cheap enough, it is important that fleet operators choose grease based on their specific needs and the type of operation they are involved in. Many operators use the same grease for everything – kingpins, fifth wheels, universal joints and so on. While a universal bumper-to-bumper, one-stop grease for all applications would make life a lot easier and eliminate the chance of errors, different components , such as the fifth wheel – benefit from using specific products best suited to it.
On speaking to a few experts in the greasing arena, FleetWatch learns that common errors in lubrication are over greasing, a lack of cleanliness, particularly on the fifth wheel, and leaving old worn out grease in the lubrication points instead of ensuring it is pushed out, by fresh grease. Another area of concern is neglecting to replace worn out seals. Grease is only as good as the seals that keep it in place and keep it clean.
Jo du Toit, GM of SAF-Holland SA, says the fifth wheel and the trailer as a whole are the two most neglected areas of commercial vehicle maintenance and he still cannot fathom why some truck operators pay millions of Rand for their capital equipment and then don’t have it in them to look after it. We’ve heard that one before.
It is common knowledge that without lubrication, the fifth wheel and trailer bolster plate literally weld themselves together. It’s called friction welding and it is potentially lethal. It is imperative that prior to lubricating the fifth wheel, the existing, dirty and worn out lubricant must be completely removed. A small amount of dirty grease left on the fifth wheel simply renders the entire batch of new lubricant useless. It is even more important that greasing is done correctly and completely. Many readers will have seen mechanics putting huge dollops of grease on the fifth wheel plate. All that happens here is that on the first coupling, the grease gets squeezed out and ends up all over the truck, trailer and along the roadside.
Manie Roux, sales and technical manager of Jost SA, advises that a thin layer – approximately 2 mm thick – of EP2 grease with graphite additive be applied on the fifth wheel top plate, the fifth wheel locking mechanism and the semi-trailer skid plate. Using multi-purpose grease for the lubrication of skid plates and fifth wheels will drastically reduce the life-span of both these components he says. Roux says further that instead of overgreasing fifth wheels, truck owners should pay more attention to how often the fifth wheel needs to be greased. The frequency of fifth wheel lubrication depends on the type of operation and operating conditions. For those who want grease out of their lives, Jost has a system called LubeTronic which is an automatic fifth wheel lubrication system. Roux says LubeTronic is specifically suited to low maintenance fifth wheels only.
Incidentally, some time ago when reading an overseas report on this very subject, it was advised that if a vehicle combination has been involved in an accident, the fifth wheel should be replaced as the only way to tell if it safe and hasn’t sustained internal damage, is via an X-Ray.
Trailer supports
If the fifth wheel and the trailer brakes are the orphans of truck maintenance, the trailer supports or landing legs are the destitute Cinderellas. It is pitiful to see the state of the supports swinging around or tied up with wire as you drive along the highway. Take a look next time you are on the highway you will be amazed and horrified all at once.
Jost SA suggest that regular (monthly is ideal) checks on the correct functioning of the trailer supports by fully winding it up and down in both gears are essential. Re-lubrication should only be done when the supports are fully wound down and greased while slowly winding the supports up. Also, only use high pressure grease with graphite additive for lubricating trailer supports.
