Welcome to the club! Richard. I complained of a similar issue in May when my flashers went inconsistent on me going up the hill to Park City, Utah, in heavy traffic after dark. I discovered they worked fine for a minute, then whacked out after that, very slow and radical.
It was suggested I replace the flasher, the clear plastic cylinder under the dash access cover ($10), but upon testing that one, I got the same result, even just sitting in a campsite in daylight with nothing else on, and no car hooked up. I'm thinking few of us try to use the emergency flasher for very long, and don't know it might not be sized right for the job. It's like the flasher unit metals don't work properly after they heat up enough.
I haven't looked into it any further, but thought I'd broach it to the guys in Bend when I go through there on the way home this fall. It is a safety issue that needs looking after. I might ask fellow BAC members to try theirs, with and without a toad hooked up and headlamps on, and report back, to see if this is a common problem. Leave the flashers on for a while, to emulate going up a steep grade and having to slow enough to merit flashers like the truckers do. You don't have to actually be on the road to test it, and I don't think it's an alternator output issue.
Joel
