There is no oil. Wheel bearings contain grease.
wheel bearing hub
It could be fly wheel bearing You may have missed a bolt, check to be sure.
You didn't say what you were working on, But it sounds like you have a bad wheel bearing Assembly and the front axel is moveing around and has gotten into the brake sensor sometime are another. Check and replace wheel bearing and sensor as needed.
Check
No, a wheel bearing should not set off a low tire pressure light in a 1999 Oldsmobile Alero.
your wheels have a censor built on the wheel bearing. the sensor could be going bad or the wheel bearing is also. if the abs light on is a sign of a wheel bearing.
check your wheel bearing
check your wheel bearing
Loose wheel, bent wheel, Belt broke in tire,BAD wheel bearing. Check and repair as needed.
check the wheel bearing
The new wheel bearing includes the ABS sensor. They are not available separately.