Have a 6L80e behind a LS3 - 408 - the transmission has a Yank Pro Truck 3200converter in it and is being controlled by a PSI Harness

Question - if I am driving the truck normally - the trans shifts normally ( all the way into 6th gear). However if I accelerate hard, do a burnout, ect..... the trans will not shift all the way into 6th - seems to shift to 5th and just stay there. If I stop and shut the truck off, restart it and take off all seems to be normal ??
The other day the trans wouldn't shift out of 2nd gear( I think it was in 2nd) ....... drove for a mile or so - shut it off.... restarted it... all seemed fine and shifted all the way to 6th

Ideas on the cause of this ??

 

Is it setting any codes?

 

I def dont have a recommendation on your issue, but damn it thats a clean Blazer!

 

Appreciate it!

I'll take it out later tomorrow and take my scanner with me and see what happens

 

Went out yesterday and it shifted just fine... curious what causes it to do this every now and then .......

 

Is the TCU maybe hitting some kind of protection/limp mode??