AUTOMATIC TRANSMISSION FAULT

Hi,
Could someone please advise me.
My 2003 Freelander TD4 Serengeti Automatic doesn"t often get a long run OUT but recently we took her on a 3 hour non stop journey and I noticed that the change ups after around 2 hours were a little bit lumpy. A few days later on the journey back I used the manual change most of the time and it seemed to be much smoother changing.
I had the Automatic Transmission Oil changed about 10000 miles ago. So any ideas?
Cheers

I had a very similar problem but with mine it was the solenoid in the gearbox a few on here have done there own look through the threds and you will find them

Rough changes are normally the 2/4 Brake Duty solenoid. It's a low resistance solenoid, so fails first.

If it helps, I changed my duty solenoid a little while ago and its not too difficult. The solenoid was £45 from a company in southampton, I removed the front bumper, dropped the gearbox oil, a couple of brakets in front of the cover plate, and then the cover plate. swapped solenoid, used a good sealent on the plate (use as little as poss) then rebuilt, around 4 hrs.

Thanks all,
At my age and with no garage or ramps I will have to get it done by my local garage.
Just a thought. Will it make any difference if I keep on using the manual option?
cheers