LBZ 6sp Hang up when shifting from 5th to 6th on WOT pulls

A couple of times when accelerating onto the highway and going wide open throttle, I’ve had a weird issue where the truck will hang up and not accelerate for a moment in 5th gear while the revs are held at about 3000 RPM at about 80km/h before eventually shifting into 6th after a couple of seconds and resuming acceleration like normal. If this something I should worry about or is that more a matter of me, just getting off the accelerator some? This happens about half the time I do WOT pulls, loaded or unloaded. I have a bully dog tow/econ tune installed.