November 2019

potential problems.” Quality On sourcing parts for clutch and transmission systems, Alistair had this to say: “My first piece of advice in this area would be to fit quality parts from a known manufacturer, not simply choose on price. It is the workshop’s reputation at the end of the day, and if rectification work is required due to faulty parts, who’s going to pay? There’s also going to be an unhappy customer. “I’d also recommend not ‘mixing C ommenting on current trends with regards to clutch and transmission systems, Schaeffler REPXPERT Alistair Mason said: “Manual gearbox cars are still very popular, so there is still a high demand for clutch repairs and replacements. The number of vehicles using self-adjusting clutches continues to increase, as they give the benefits of a lighter clutch operation with a consistent bite point and clamp load. “We are now seeing the use of hydro-electric clutches in semi- automatic transmissions, where an electrical actuator controls hydraulic pressure to the concentric slave cylinder to operate the clutch. A position sensor is fitted to the slave cylinder to give feedback on the clutch position. “The future is in electrically- controlled clutches, which will also help reduce vehicle emissions, allowing the car to coast wherever possible. “Double clutch systems are also now being used by most vehicle manufacturers. The main advantage is the gearchange speed – which can be as quick as 0.08 seconds. Because of this, when accelerating, drivers tend to hold the throttle in one position until the desired speed is reached, and then they lift slightly to maintain that speed. As a result, it is lot easier for the vehicle to run at Lambda 1 to aid emissions control and, because the gearbox is controlled by an ECU, it is always in the correct gear. The dry double clutch system is the most efficient as there is no drag on the clutch.” Lubrication With gearboxes, lubrication is the name of the game says Alistair: 46 AFTERMARKET NOVEMBER 2019 CLUTCH AND TRANSMISSION www.aftermarketonline.net DOUBLE-DE-CLUTCH... DOUBLE THE PROFIT? Above: Keeping up with clutch systems is vital Engines are changing, so the clutch and transmission system is being adapted too. Are you staying up to date with the latest on technology and methods? “Generally, the only maintenance required on the transmission system is to change the oil on automatic, wet double clutch and constantly variable gearboxes. This is because the oil becomes contaminated as the clutch wears, losing its lubricating properties as it deteriorates, causing premature wear on associated components, leading to expensive repair bills. “Another area to look at, to ensure gearboxes are maintained properly, is the control unit software. VMs are constantly modifying software to optimise systems and prevent