That would be nice but it's a fallacy anymore!
Most all parts stores test batteries but load testing is assumption based on other factors.
If your battery is old you ought to go ahead and get a new one.
If you're looking for justification to keep the one you have, you sure will get plenty of that but you already have a suspicion that the battery is bad and it just may be you're trying to save some money.
The best battery to get is one that you fill yourself. That way you know it is new. You must also
charge the battery according to the direction that come with the new battery. Failure to do this will reduce the battery life and also reduce the capability of the battery.
Go ahead and bite the bullet and get a new battery.
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