This is a maintenance free battery, which are normally very good for 3 to 4 years .
if the battery is this old then time to replace ,
If you have a voltmeter do the following test .
Connect a voltmeter to the battery .
A good fully charged battery will have 12.6+ volts ,
With the voltmeter still hooked up switch on the head light and start the engine ,keeping an eye on the voltmeter
a good battery will not drop below 10.6volts if it does replace .
When the engine starts the voltage should be 14volts +/- .5volts .
Next if the voltage test show good then you may have a parasitic battery drain where some thing is draining the battery .
This you will need to test .
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