Auto Gearbox Shudder Only In Change Up To 4th Gear

Hey

I'm getting a gearbox shudder on the upshift to the 4th gear in my Auto D2.
If my Disco is slowly accelerating into that gear, the shudder is longer into the change. If the acceleration is high, the shudder is quicker.
In both cases, she drives fine before and after the change up and in all the other gears, the change is smooth. Nothing on the change down.

Any thoughts on what it could be?

What's the service history?

Sounds like it would benefit from a fluid and filter change.

Service history is good... but I need to check the docs.... see when gearbox was last done
I thought it would be something more severe than a fluid filter change...

Oil and filter, well more the oil than the filter and if it still does it a couple of tubes of Dr Tanny will work wonders.

For a moment, I thought you wrote Dr Tranny...

Thanks for the info!

Oops... it is Dr Tranny!

may i ask, yeh i know, lol, was the issue there before u fitted the new wheels and tyres

Yes... the shuddering has been with the car for over 6 months.. Hasn't gotten any worse.
The wheels were just done a few days back and there's no difference....it's not any worse.