Is it common to have to have a transmission replaced and what will occur next? on 2001 Nissan Altima

My transmission is missing and received estimate that it needs to be replaced. No check engine light is on nor problems with diagnostic testing. Is this normal and what can I expect next. Mileage is at 157,000.

Asked by for the 2001 Nissan Altima
good mileage for trans. when it wears out, there will be no codes. if you plan to keep the car, get a quality job with a good warranty.