05 Honda Odyssey - drop in rpm

Hi, I have a '05 Honda odyssey that has recently started showing drop in rpms at approx 30MPH. At that speed, I see that RPM suddenly drops from 2500 to 2000, pressing on gas really hard, triggers downshifting of gears and everything comes back to normal. I suspect some issues with how gears are being shifted, would like some thoughts.

Sounds to me like you’re seeing the perfectly normal results of your torque converter clutch locking up - and then unlocking when you stomp on it.

But when this happens (rpm drop that is), the car jerks and feels just like how one would feel when driving a manual shift car in 4th gear at 30mph.

You didn’t say anything about jerking. All you said is that the rpms drop.

Presumably your comparison to driving at 30mph in 4th gear is another way of saying that the van is jerking? As if the engine is chugging? In that case, I’d still say it is the torque converter clutch (TCC) locking up but that you are experiencing TCC shudder - as in the clutch is not locking up smoothly.

Perhaps now would be a good time to reveal other information - like the number of miles on the van and how often and by what methods the transmission has been serviced.