I was driving my disco all day long and as soon as I drove up in the driveway to my house, check oil light came on why ????? I heard no ticking no clanking and I do have a full tank of oil. Nothing smells burned no smoke coming out of the tailpipe so I’m bumped and confused.

 

If you are in a very hot climate right now could cause the light to come on if you are running a lower weight oil
a failing/leaking oil pressure switch can cause it - of course oil pump issues if it hasn't been changed out over the years/mileage

 

Does the light go out at higher RPMs, then back on at idle? Maybe check the actual pressure with a gauge. Oil light switch activates when oil pressure drops below 8 psi or so, as I recall. Checking actual pressure may involve removing the oil pressure switch, so maybe get a new one to pop in its place after the test, and install thicker oil, like 96 said.