can you try this...
when you driving at 150km/h in 4 gear, before your masuk 5th gear, when the clutch pedal is pressed, rev to 4500rpm then masuk 5th gear, try to give rpm around 4500 when you actually masuk 5th gear. is it ok without "krggg" sound ?
i suppose 5 gear running at 4500rpm at 150 km/h.
how is it ?