so i put B8.4D led bulbs in the gauge cluster of my 2006 dodge ram. they will on turn on, but then a second after they come on they all shut off. i dont know if i need some sorta resistor or what? thanks for the help.
It's possible that you've put them in rotated 180°; their polarity is reversed. The B8.4D bulb will fit in either direction, but many LED 'replacement' bulbs are polarity sensitive. Flip 'em around!