...Inside the transmission. Uh, what do I do? I am thinking the retaining clip came off and the whole thing slipped off the end of the speedometer cable. I know nothing about working on transmissions, should I just take it to a shop or is there another solution? Thanks.
If you've got some wheel ramps, a floor jack and basic hand tools, you can fix it yourself. Drive up the ramps, block the rear wheels. Then if you can fit under the car, get under it, place the jack under the transmission crossmember. Unbolt the X member and transmission mount. Then remove the driveshaft. Then drain the oil from the transmission. Manual trans, remove the bottom tailhousing bolt and drain the oil into a pan. Auto trans will be messier, but place a catch pan under the tailhousing and remove the housing bolts. Once you slide the tailhousing off, the speedo gear will be inside the housing.