Hi.
Im hoping someone can help me with suggestions, im not near a mechanic or shop to just nip it in and dont want to drive 55kmph at 3000rpm for 3hrs to the nearest place.

I have a patrol 3.0L zd30 with the auto box RE4R03A. a couple of months ago i changed the tranny oil and put in a new filter, its been fine with no issues at all. Yesterday i went out 4wheel driving with a friend, nothing serious just some water and little inclines. I put it in 4wd but never used low.
Everything was fine till i got back on the main road and started driving. It got to about 60 then when it should have gone into 3rd it seemed like it went back into first or neutral. IVe tried everything. 1st manual works, 2nd manual works and thats how i drove home in 2nd gear at 55kph.
I was hoping it was water in electrics but this morning after 15hrs its still the same
No check eng light either.
I do have ecutalk the the consult cable and checked for errors and nothing logged.

I look forward to any suggestions to try or if anyone knows straight away the problem.

PS the oil isn't watery nor does it smell burnt, its very clean like new still.