SET light blinks and only 1st gear working

[jacker]

Need help with A/T
when I drive for over 30 min with speed over 55 MPH or above 2000 rpm SET light start flashing and A/T start switching gears up and down and finaly I have only 1st gear to use.
my driving on long distances are usually with cruise control ON and 3 MPH above speed limit.
today I drove one way with cruise control ON and problem started after 40 min of driving (40 miles) and when I pull over turn off car for 10 - 20 sec and I was able to drive for 2 min and than again problem.
on the way back I drove within 1500-1800 rpm and no problem the whole 53 miles.
what problems do I have that I know about:
6 years ago radiator blow and sprayed whole engine compartment
4 years ago cd changer problem with reading cds - never fixed
2 years ago left site collision with another car and new head light - fixed by insurance
1 year ago subwoofer quit working - never fixed
and resent led light in the spoiler half working and half blinking
Please help
Thank you
Jack

[loystock]

Did you check the level and color of the ATF? Did you use OEM radiator as a replacement for the busted one? Do you have external ATF cooler? When was the last time the ATF flushed or drained-refilled. You may have a worn out ATF fluid and restriced cooling line.

[jacker]

Did you check the level and color of the ATF? Did you use OEM radiator as a replacement for the busted one? Do you have external ATF cooler? When was the last time the ATF flushed or drained-refilled. You may have a worn out ATF fluid and restriced cooling line.

Did you check the level and color of the ATF - Yes level is ok and color between Rose and Pink
Did you use OEM radiator as a replacement for the busted one - i think it was aftermarket
Do you have external ATF cooler - NO
When was the last time the ATF flushed or drained-refilled - Flushed in 2010 at 131 000 (currently 146 000) by TirePlus

Thank You for help