I have a transmission problem I cannot figure out.

I have a 1989 Volvo 760 Turbo.
It has AW 71 transmission.

The problem occurred about 2 weeks ago.
One night I travelling long distance (to Chicago 120 miles away from home).
On the way there I had set up the cruise control at 75 MPH.
The next morning when I was returning home, it would not shift out of second gear.
I drive back the car at 55 MPH at 4500 RPM.

Now here are some prior work on the transmission.
The transmission kick down cable had been replaced like 5 weeks before the problem.
The rear transmission bushing and seal were also changed at the same time.
The pan gasket and some new fluid were also done at the same time.

I did check the morning of the problem that the kickdown cable was working fine.

When I returned, I first removed the rear cover where the bushing was and
removed the governor. I cleaned it out real well and made sure the moving parts
were not sticking. Then I put back in.

That did not solve the problem.

Next, I did a complete flush of the transmission.
That did not solve the problem.

I am not sure what to look for next.

If you have some suggestions about possible problems and their solutions please let me know.

Juan Moran