May add a few months to the life of a tire that sits most of its life.
Carlisle says:
Time and the elements weaken a trailer tire.
– 3 to 5 years is the average life expectancy of a trailer tire,regardless of mileage.
– It is estimated that in approximately three years, roughly one-third of a tire's strength is gone
– After three years, depending upon storage and conditions of usage, consider replacing trailer tires even if they have tread depth remaining.
– After five years, trailer tires should be replaced in all cases
– If you experience a series of successive blowouts, something is wrong with your setup, it is not a tire problem.