10th August
Left Bathurst @ 10am at 12pm outside Wellington doing 110kph, gearbox stated to shift between 3rd and 4th and revved to 3 grand back down to 2100rpms, dropped back to 100kms and revs sat at 1900rpm to 2k no issue accelerated to 110kph no issue..

Left Geurie @ 4:40pm accelerated to 110kph rev range 2500rpm car pulsated between 3rd Gear & 4th Gear then car seemed like it found 4th got to 110kph revs dropped at 2000/2100rpm

8:30pm Left Dubbo @ 100kph car started to vibrate and shudder slowed down to 80/90kph, car acted like it was trying to find a gear etc pulled over turned around and parked that car up at parents.

23rd August
Father took it All Trans Mechanical they “couldn’t” connect it to the computer / diagnosis and didn’t touch it, my father picked the car up and took it to Dubbo Transmissions and all he could do was a service and suggested a possible clutch issue.

29th August
So I finally was able to pick the car up from parents and drove it back 199kms to home and left parents place drop for about 49 mins into the trip, it started to shudder, I pulled over let it sit and then sat on about 80kms and made sure car didn’t rev over 2100rpms drove for another 40 odd minutes or so pulled over and let it sit the drove remaining trip roughly 52 kms and no issues what so ever I sat on 100 and gave it a squirt now and then up to 110/120 and it didn’t miss a beat.

I've brought a new inhibitor switch to replace in the coming days so if that doesn't rectify the issue I guess its a torque converter issue?

Auto not wanting to select gears is usually failed solenoid or a blocked fluid channel in the trans.
Could also be torque converter related, & if it is, best to replace the whole trans.

I’ve pretty much said f**k it and taken to trans place and was told 2500 to rebuild or whatever I told old mate do what ya gotta do.

Find a reco shop that will take the old trans as a part payment on a rebuilt one.
Should get change out of 2k I'd think.

The trans (bought used) in my AU2 was a reco/trade about 5 or 6 years ago, 220k clocked up & still runs perfectly.
Cost the guy about 1500 at the time to exchange.