In what way, exactly, has it been erratic?

Does the flash rate vary (e.g., sometimes normal, yet sometimes faster than normal)?
If it's sometimes faster than normal, that points to a bad bulb or bad ground (when one bulb is blown or isn't grounded, the flasher will increase its rate).

Or, does it sometimes not blink?
Sometimes, the contacts in the lever's base (the multi-function switch) go bad -- not always making contact (that's an expensive switch to replace because of all its functions, though, so you could try to remove it and spray it with electronic contact cleaner).

Anyway, when flashers or turn signal relays fail, they usually just die, rather than become "erratic", so it might be something other than the relay. In any case, try to give us more descriptive symptoms of the problem.

Regards,