I know I've driven home at -20C and had my Scan Gauge II indicate a coolant temperature of 90C. A couple of hours later when I start the Jeep again the coolant temperature is roughly 30C, so it doesn't cool that quickly.

I suspect what could be happening is that the transmission is over heating and while it is operating the is sufficient air flow to keep it partially cooled. However once it is shutdown and the transmission oil is no longer circulating it starts to heat and possible boil over causing a fire. I don't know enough about the automatic transmission to know if this is a possibility or not.

 

I hope the ministry is informed so they will look into it and do a recall..

Wonder if a tranny cooler would help?

Year and model of this one?

Also there is a flash update for the automatics for slow shifting when cold ...........

 

I wouldn't think so, tried lighting my gerage firestove with ATF fluid over wet wood and found out it's not very flamable at all, not like regular motor oil.
I'd think built up debris around a heat sheild possibly around the cats lit it up. I think this as I'v had my 4 wheeler light on fire a couple times from grass build up between the muffler and it's heat sheild (thankfully the smoke is easy to notice on a bike).
Have trouble beliving a tranny could get that hot but I never had an auto before so maybe.

 

at running temperature it will flare up it is the extreme temp of the exhaust that cause it to flame

it overheats then boils up the check tube and hits the exhaust then boom