my brake lights function properly but the driver side inner bulb keeps blowing out, i have replaced it 3 times...what should i check. i believe the fuses are okay.

 

Check the Fuses, or the good old trick just hit it a couple times.

 

check the wires..there could be a short inthe plug or something could be reversed..

 

The bulb keeps blowing? Obviously it's getting power... so that rules out shorts or fuses!

If you are using the correct bulb, either water is getting at it, for some reason it's getting more current than it should (shared circuit with turn signal, etc), or it's getting vibrated to death.