Agree with 4100 fire truck but the drain can be milliamps. Best way to detect parasitic drain is install millamp reading meter between disconnected neg cable and neg post.
Do you have ANY modern components? Radio, blu tooth, security alarm, CD player ........
No: the turn signal will not drain unless malfunction of them or any other item.
You need to check voltage across battery posts when parked and check again after one week. Truck not running for either check. Report voltage readings.
Doesn't NAPA test the battery before replacing?
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
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