2005 F-250 Tranny Problem after new FICM???

[Dawgman]

Don't know what to do here. I had my FICM replaced a few weeks ago, and just recently downloaded and installed a new update for my Diablo Predator. Installed the "performance tune" about a week ago, and all has been going well.....power improvement, great shifting, and the fuel mileage is better.

Something really odd happened today. I was driving casually at about 60 mph, went to accelerate, and my RPM's shot way up then the transmission shifted VERY hard, and then the speed started to decrease, while RPM's were still up....This happened off and on for about 20 miles until I got home (the tranny shifted so hard at times, I thought it was going to blow). I restored to original back up on my Predator, and went for a drive. No problems.

Tuner problem?
Trans gone?
Sensors?

Thoughts?

Thanks!

Eric D
2005 F-250 4x4
158,200 Miles