2003 Escape Transmission?? SURGE

I recently bought a 2003 Escape 4X4 used. It is a V6 automatic. I drove it around in the city for about a day with no problems. Took it out on the highway, and after about an hour and a half, the vehicle began to surge.

In drive, under constant speed, the vehicle would surge, and the RMP's would rise and fall by about 1000. The speed didn't change and I didn't have to increase gas.

The check engine light came on. But when the vehicle was put into 2nd from the drive position, the surging stopped.

The transmission fluid level is slightly high.

There have been no grinding sounds and the vehicle will still move and drive.

After buying the vehicle, when it was put into reverse, there was a hesitation, then it would engage. Now, it will go into the reverse position, but it will not engage, the engine just revs.

Any suggestions.

I am going to take it into a transmission specialist, but I was wondering if there were any suggestions of what it might be, or specific areas that I might have checked and not be gauged on the assessment.

THANKS!!!

Pull the engine code first.
Second, the EGR sensor, a know problem can also cause surging.
Third, take it to a transmission shop. How many miles on the vehicle?

Thanks for the suggestions. I have taken it in for a couple of diagnostics. There are a few differences in what is being told to me. But it is at a transmission shop now.

The vehicle has 105,000 km. So, there really shouldn't be anything major wrong with it.