You've taken the time to import the best kei truck/van money can buy, so keep that engine running longer - your Subaru Sambar (スバル サンバー) deserves it. Simply put, an Oil Catch Can Tank keeps oil vapors from entering the air intake (by way of PCV) - reducing carbon deposits. Too much of a buildup can lead to cold start misfires, poor fuel economy, and, eventually, a reduction in engine power. For these 25+ year old motors, it's better late than never since they will/do get driven harder here in the states.
