Seems like most relavent place to ask this.
I have an 07 classic that the oil pressure gauge is always pegged at 80 psi until you floor it, then it goes to 0 and get a warning chime. Let off the gas, pressure goes back to 80 psi. I replaced the stepper motor in the cluster and it had no effect.
I also have an 05 yukon denali that does the exact same thing , low oil pressure warning chimes all the time when driving. Oil sending unit on this one was changed about a year ago, but not the stepper.
Any ideas? Thanks