Transmission issue - what could be wrong?

My wife has a 2003 Honda Odyssey with 160k miles. For the past several years, once the car is up to speed, you can’t manually shift the transmission lever past D. For the most part, this isn’t a problem, since the area where we live and drive (NY metro area) is almost completely flat. However, occasionally we venture upstate and encounter hills, where it would be advantageous to be able to downshift to avoid overheating the brakes during descent. Other than this, the transmission seems fine.

More than anything else, I’m just curious as to what the cause could be. When I described it to a mechanic at the dealership (we had it in for some other services) he said it could be the transmission itself and asked if the Check Engine light was on (it wasn’t, and never has been). It would cost us $250 to fix, no matter what the problem (extended warranty with deductible).

Hi- My wife has a 2002-Trans had a multitude of probs found via google, recalls/fix notice and class action lawsuit, so see if any with your year, Good Luck!

It could be something very simple. If this is a console shift something might have slipped into the housing that prevents the lever from moving. At least check out things like that before you lay out $250. OTOH, if it’s covered under the warranty that’s pretty cheap for a transmission service, maybe you want to do it anyway.

It’s probably not worth the $250 to fix since it’s extremely rare that we actually want to downshift, and there’s never been an instance where the brakes were insufficient. I’m curious more than anything. It is a console shift, but I doubt it’s something that slipped, since it works when the car is first started.