Perodua Engine Oil - Lousy Container Design

My complain to Perodua.

The semi synthethic engine oil bottle cap design is bad. I always request to the remaining oil to keep for next service to save money. And EVERYTIME it leaks! For an item costing nearly a hundred ringgit, you'd hope the design is robust and not leaky. Please help fix the design of the container.

ps- besides the above complain, I am ACTUALLY FULLY SATISFIED with their service quality. Very professional, and friendly. Great follow up usually as well.

UPDATED:
1 March 09 - Perodua called me up to understand my concerns. They will now look into this.