I have some 18 inch rims on my 03 Cav. Shortly after riding with them for a while my speedometer started acting up. Sometimes it gets stuck at a certain speed & sometimes it just bottoms out to 0 and doesn't move. It does this maybe 2 out of 4 times I'm driving. After I shut off & crank up a couple times it resets itself. I read that changing rim sizes will sometimes cause this. How can I get my speedometer to work correctly without going to the dealership. We all know they are crooks & thieves.... lol

doesnt sound like anythin' w/ the wheels. sometimes the wheels throw the speedo off a few mph but not like your saying. if i were you, id check out my vss on the tranny. if its covered in metal flakes, well save up for a new tranny