slow when switching gear in van

check your trans fluid level..maybe change trans fluid and filter..

Kapetan is correct. I would cease operation of the vehicle until you can check that Transmission fluid at a cold level (let the van sit overnight). If the fluid is not dirty (meaning pinkish and see through), I would have the vehicle towed to a reputable repair shop or the Honda Dealer. Honda's are known for being extremely reliable. Do you know when the last transmission fluid and filter change occurred? I would ensure that has been done, or gets done as well. The shop will be able to see if the fluid is "burnt" or has metal shavings in it which would indicate an issue with the transmission's operations (i.e. gears, selector, etc.). Best of luck! I hope this helps!