1st to 2nd soft then jolt 2002 7.3

[Maverick4x4]

2002 Excursion 7.3. No engine/tranny/exhaust mods.

Hauled the jeep out yesterday and back today. 100 miles each way, 65-80mph. Stiff headwind, hammer down all the way back to maintain highway speeds. Engine and Tranny temps normal. When I got off the freeway, the 1st to 2nd shift was soft, with a slight loss of power then a jolt if I was in the throttle.

After I got back and unloaded, I let it cool for several hours, then took it for a spin and it still did it.

Thoughts?

Thanks,
Brett