I drive a 99 wrangler and am having similar problems. The other day leaving school I could hear a loud ticking noise sounding like it was coming from the engine. Took of the valve covers and checked the valve springs, rocker arms, and push rods, couldn't find the problem. Then I borrowed a tool called an ear and found out that it was coming from my transmission. You most likely have the AX15 transmission same as me. I suggest lifting it, and verifying that the sound is coming through the transmission then take of your starter and inspection plate
Throw-out bearing................
When parking, especially on a hill, the hand brake should be fully engaged When you are driving a manual transmission vehicle, the handbrake can be partially engaged to give you better control as you push the clutch and gas when starting from a stopped position going uphill, so you don't roll backwards.
A car is in gear when the clutch is engaged on the transmission
Can be a throw out bearing in the clutch assembly going bad.
Synchros in a manual transmission are used to slow down the gear before it is engaged so it doesnt grind
either the shifter linkage is not fully engaged in park or the park lock is broke inside the transmission
The hot oil warning light is not for the engine oil, it's indicating the auto transmission oil is too hot. If you are climbing a long hill with the over drive engaged (button in front of shifter) it will constantly shift jumping in and out of a lower gear. With the 4hi engaged it adds addition work load to an already hot tranny. If the light comes on stop and left the engine idle in park for 5 minutes. Turn off the OD and continue on.
Four speeds on your transmission and the overdrive is when the engine speed and the transmission speed are engaged is a interchangeable load. running "free" sort of
Your transmission/gearbox is either not engaged or its out of commision.
higher-level awareness
maritime trade and those engaged in it.
Perhaps clutch throw-out bearing?