Ghost in the machine...?

My 07 acted up this afternoon on the highway...
Cruise set at 65 ish on fairly flat terrain and about 300lbs in the bed. I notice that it seemed to be hunting for gear between 4 and Drive, although not aggressively searching. As I started paying closer attention to the speedometer started skipping down to about 40mhp then back to actual speed. I shut off the cruise and appeared to have the desired power to accelerate. I hit my exit and didn't notice the issue at slower speeds.

Hope this isn't going to become a transmission or electrical issue.

Note I have not serviced the trans fluid as I am the 2nd owner and had no records of previous trans fluid services. Current 171,000.

Any thoughts?

 

Possible sign of fuel pump on it's way out

 

To me that sounds more like a wheel speed sensor issue

 

I think you nailed it.
I just did the hub and bearing assembly and know I have at least one that is bad. ABS and Brake Light is on.

Sure looks like a real price swing on RockAuto. $12 - $115. Any advice?