Maintaining Permanent Residence

Is there a limit to how long one can be out of Mexico and still remain a permanent resident? Gracias.

No.

Really? So one could relocate back NOB for a year or two and then return with no effect?

I understand that if you are gone...and that they know it...for 5 yrs.....you lose your status

You are required to report any change of address in Mexico to Immigration. So if you sell your house or stop leasing a place here, you'd technically have to report to them that you have left Mexico. Not sure how'd they know though.