VXOC Astra-J/GTC

My 2013 Astra-J 2.0 CDTi auto is starting to play up when taken on a journey of more than 10 miles. Driving around locally it’s fine, but putting it into D after approx 10 miles or more, it snatches into gear quite violently like the clutch has gone in a manual box. If I turn the engine off and start it up again, then it’s fine for a little while. No error codes (using Op-Com).

It's done approx. 65,000 miles. Am I right in assuming it's the AF40 autobox?

The gearbox oil has never been changed, but then again all my previous Vauxhall autos had done over 100,000 miles without an oil change and had no problems.

Would something as simple as an oil change likely to resolve this problem?
How easy/hard is it to change the oil, and does anything else need changing, such as a filter?

Thanks.

Disappointing I didn't get any replies.

I contacted my local Vx dealer yesterday. They said changing the oil is the 1st thing to do, and also the cheapest option.

So, £104 to change the oil (with my 25% Masterfit service club discount).
Not worth me attempting to change it myself by the time I've bought the oil, and the only flat level area I have available is the garage floor, but there isn't any room to work on the car in the garage at home.

I would agree, easiest and cheapest place to start. Surprising sometimes prices at dealers, in a good way although they can produce some shockers.