97 flasher / turn signal / trans - related?

[riverdogs]

Howdy all...
I have a 97 F350 4x4 crew (canadian) that was chipped and had an exhaust brake put on it in Canada before I bought it. I've owned for 4 years now and had very little serious trouble with it. I had the trnas fluid changed when I bought it (75k miles) and had a deep sump aluminum pan and cooler installed. I've never been stranded other than a water pump.......and an intermittent power window switch issue(some windows work, some don't from the drivers door....but they all work at the individual door switch), and a drivers door dome lamp swtch that is inop.
Now....at around 150k miles I have an interesting problem. Recently, I noticed that my turnsignals would stop flashing (although they would illuminate the lenses, and the indicators in the dash). Replace the flasher and the problem goes away. A few weeks down the road, it appears again. Today, out of the blue while cruising under a light load, just as the trans shifted into high gear and the converter locked up, the ABS light came on in the dash and the trans shifted out of OD. I didn't realize the trans stayed out of OD as I arrived where I was going. Later, when I left for home I noticed the dash light is still on, I have no OD (pressing the button on the column shifter did nothing), and I have no turnsignals (nothing now at all, in or out of the truck). A check at home of the fuses found nothing, and a check of headlights and tailights found them to be ok as well.
I let it set for an hour or two and just wnt out and fired it up.....yep, abs light is on, and then went out like it's suppossed to. turnsignals ? nadda, nothing, no click, no flash, no nothing. Will a scanner locate this (there is no check engine light, thus no codes? )

perplexed and driving daylight hours only now...yuk!

[power95]

little advice DO NOT USE OVERDRIVE WHILE PULLING!!!!!! no matter how small the load isu probaly fried your OD, as for the blinkers your flasher probaly went out again

[riverdogs]

no, by light load I meant partial throttle.....nothing in the bed. I seldom pull or haul anything, and really very, very seldom get pass half throttle when i drive it.

[power95]

u havent been doing an brakestands have u?:burnout

[riverdogs]

Well....just a little feedback.
I had a shop down the road troubleshoot it and it was merely a bad turn signal switch. The switch fixed the non flashing signals and the brake lights. Once the brake lights were no longer inoperative, that cured the overdrive light and trans.
It's all interwoven......crazy.