Replacing taillights

4x4van wrote:
If your trailer turn signals are simply wired in to your tow vehicle's turn signals, the "fast flash" likely won't be an issue since there will still be sufficient load on the turn signal circuit because of the tow vehicle's lights. If, on the other hand, the trailer turn signal circuit on the tow vehicle has it's own separate circuit/flasher, then the "fast flash" could be an issue, although it can easily be solved by wiring in a resistor to add load and fool the flasher unit.

While the trailer lights may be a separate circuit (and indeed not infrequently are), I would be very surprised if any vehicle uses a separate flasher for the trailer turn signals. That would mean that the trailer and tow vehicle flashes would not be in sync with each other, which at the least would be confusing to drivers following (who might quite reasonably think it to be two separate vehicles).