Does anyone know if there is a way to test if the LT77 oil pump is working. I have replaced fibre gear with uprated metal oil pump gear. However the gearbox has a rumbling noise when the car has been run for a while and the oil is hot. more noticable when gearbox is operating in overun. All gears operate smoothly (hot or cold) and Gearbox does not make a noise when cold. I am using Castrol VMX80 manual gearbox oil.
I seem to remember that there is a procedure for testing operation of oil pump.
Your help is very much appreciated.
