Rev surge into top gear

[MudSurfer]

Hi all, got an odd one on her Surf. Driving it on Sunday, as you get to top gear, the revs surge then it goes into O/D. It also seems really flat unless you push quite hard on the throttle, it usually goes much better than this. To get it to downshift I had to floor it too, all f this is around 45-50 mph, takes an age to climb up to 60. ATF is new in Feb, is it likely to be the cable needing adjustment of an ECU on the way out?

It's on 236000 miles now (not KMs)

TIA

[budweiser]

same happening on mine

[tashtego]

Pull the OD codes ( paper clip bridging TE1 and E1, count OD light flashes) to exclude electrical/solenoid type problems.

Cheers

[soramad]

It could be low or old transmission fluid, worth having a check, red fluid ok, brown needs replacing, check capacity by getting the fluid hot ( driving) shift it through the gears and check the level with the engine running (in neutral) , should read at the hot level mark.

[RebelV8]

It could be low or old transmission fluid, worth having a check, red fluid ok, brown needs replacing, check capacity by getting the fluid hot ( driving) shift it through the gears and check the level with the engine running (in neutral) , should read at the hot level mark.

I've always checked my level the same by following the same details above, except, it should be in park, not neutral.

However, if the transmission fluid was changed in February, was the transmission fluid filter changed at the same time?
After you'd driven it for a few miles did you check the fluid level and top up if required?
If the fluid was changed at a garage, are you absolutely certain that they actually changed it?

[MudSurfer]

I changed the transmission in June, including a new filter. Changed the ATF again in Feb to make sure it had filtered out any of the old stuff, and it's just started doing this.

I'll check the codes this weekend and see if anything comes up.