of El Cajon, California purchased all the overdrive assets of GKN to continue production of the U.S. version and all spares for J and P types worldwide. The system features an oil pressure operated device attached to the back of the standard gearbox operating on the gearbox output shaft. Through a system of oil pressure, solenoids and pistons, the overdrive would drop the revs on whatever gears it was used on by 22% (.778). For instance, the overdrive system applied to a Triumph TR5 operates on 2nd, 3rd and top gear. When engaged, the overdrive would drop the revs from 3000 by 666 RPM, or from 3500 the drop would be 777 RPM to 2723 net. The advantages this reduced rpm had on fuel consumption was most often quite near 22% decrease during highway driving. I don't have any idea whether or not Gear Vendors has anything for the type D / Alpine overdrive unit, but they are the successor to Laycock and GKN. J Type Overdrive Hydraulic Oil Pressure Gauge Test Set - Functionally equal to / better than Churchill L, which has long been out of production and not commercially available.I do know that Gear Vendors overdrive units are used in some enormously powerful rear drive cars. Title: PUBLICATION PART No Author: The Youngs Created Date: 1/7/ AMMissing: j-type. Whilst there have been few major changes in the Overdrive Unit itself, since it was first fitted to our vehicles, there have beenFile Size: 2MB. This Manual has been compiled with a view to familiarising our Agents and other Repairers, throughout the World, with the operation and repair of the Laycock de Normanville Overdrive Unit. Whilst there have been few major changes in the Overdrive Unit itself, since it was first fitted to our vehicles, there have been alterations. J Type Overdrive Hydraulic Oil Pressure Gauge Test Set - Functionally equal to / better than Churchill L, which has long been out of production and not commercially available.

If your J Type Overdrive is not functioning properly, this primary diagnostic tool will help you determine and solve the problem.

The Laycock hydraulic system and the solenoid circuit varied slightly according to the overdrive model type and its applications.

Laycock overdrive j type