American car or Japanese car,which one has higher quality?  

I think American car has a better quality. As they are heavier and uses thicker material. The shortcoming is it runs out gas so soon. If you don't have to worry about it, then it's a good choice.

Dear friend,
I had know that Americans are good in big cars and whereas Japanese are good in compact cars. Technology wise they both has their own merits if more automatic cars and more computerised technology is used it would be better for a Japanese car. Moreover safety measures I hope American cars are better. The both has their own ways of good products. Price wise American cars are costly compared to Japanese. For luxury American cars are best. It whole depends upon the needs of buyers.