Did you ever get any answers? A few weeks ago my truck (14 CCSB 5.3 Silverado) threw "Transmission Hot Idle Engine" and went into limp mode. Since then I've had the truck to the dealer twice, since it's still under the powertrain warranty, and they "cannot recreate the problem" or get the truck to throw any codes. They also can't get the trans fluid temp over 225. Well within a day or two of picking the truck up from the dealer, two weeks in a row, I've got the trans fluid to 243 and 261. Today it started shifting hard and the check engine light came on, it was U0101. Had Autozone print the code sheet so I can get it to the dealer tomorrow.
