Are you tightening the belt to the specs? Take it to an AutoZone or similar and they will check your alternator for free. It should give you a reading of 13.8 and 14.2 volts. If lower than that it will not charge the battery. So you probably have a wrong or bad alternator to begin with.
No alternator goes bad after 4 months, regardless if OEM or aftermarket.
you failed in this question, not knowing the brand.or car makes it impossible to come up with any answer that would be of any use.the year is also needed to see if this has been a problem with this car line. Sounds like a voltage regulator problem.To me, not all cars have a regulator built into the alternator. again not know any info, can be of no help.
What year, make, model, and options/accessories is your vehicle?
What is the problem?
What is the history of this problem and/or vehicle?
No offense, but you gave us little/questionable info.
well If your buying after market alternators they wont last , try a new OEM original and that should last .
We need more info. Are you buying rebuilt alternators? How long did each one last?
The last time it went out I bought a knew battery thinking that might have caused it but no luck.
