Replacement flasher for high current draw

I think you need a solid state replacement for your factory mechanical flasher control unit.
Maybe try one out, see if your system can bear the load. Need clean and good connectors and wiring from the battery, front of car to the tail lights.

http://www.wiringproducts.com/contents/en-us/d140_automotive_flashers.html

two variants of electro-mechanical replacement flashers on this page..

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