Trans downshifts hard while slowing

[JdmVibe]

I've noticed this problem for a while now, but it seems like its getting worse here lately.
Whenever im slowing to a stop above 30 mph or so the trans downshifts hard and the rpms
skyrocket. Oddly enough it doesnt do it when i apply the brakes a little harder. can anyone
tell me what this is?

Thanks.

[vibenvy]

What year is your Vibe and is it an auto or manual?

[JdmVibe]

03, Auto, base model.

[Chiadog]

Try pulling codes with a scan tool or find a mechanic with an advanced scan tool that has a remote unit that plugs into the OBD2 data link connector while you're driving. Sounds like a faulty speed sensor sending bogus information to the transmission. Beyond that I'd consider changing the tranny fluid, but that's a long shot.

[JdmVibe]

Changing the tranny fluid tomorrow after work hopefully. so ill keep you posted. thanks for the tip.