T5, auto hesitates changing into 4th gear then clunk

[Rebuild]

Maybe the fill location changed on later models.
As i said, i think you should seek the opinion of a transmission specialist

[jets]

Thanks for all of the help!
I have added some Penrith full synthetic atf

Do not start mixing oils, use the VW oil.

[ImmortalT5]

How often should you service auto trans?
Mine was last serviced 35k ago

[ImmortalT5]

So it has been getting stuck in 5th gear and very little power and tiptronic can’t make it change either, got engine light on and error po735
Changed fluid and filter and it was better for a second but then pretty much back to bad, it isn’t as bad now but still bad,
Does anyone know what the transmission sensors are called?
Shops only have “speed sensors”

[Rebuild]

i planned on doing partial changes once i started, every 75K km or so.Now gearbox is fixed, next oil and filter around 235K

i guess you've seen this or similar
17119/P0735/001845 - Ross-Tech Wiki

[ImmortalT5]

Car keeps going into safe mode stuck in gears loses power feels like it is only partially in gear, so now it is at the shop hopefully it doesn’t cost too much, vw said the sensors might be part of the valve body and will cost $2.5k so hopefully it is something cheaper...

[Sunny43.5]

Car keeps going into safe mode stuck in gears loses power feels like it is only partially in gear, so now it is at the shop hopefully it doesn’t cost too much, vw said the sensors might be part of the valve body and will cost $2.5k so hopefully it is something cheaper...

I know this might sound far out but could there be an issue with the Turbo ? When our tranny went to lunch we had it rebuilt and then found ours failing to change up a few times it kept throwing up Turbo Overboost on fault codes . After we fitted a second hand Turbo it was fine again . It would go into limp mode at oddball times .

[Rebuild]

Car keeps going into safe mode stuck in gears loses power feels like it is only partially in gear, so now it is at the shop hopefully it doesn’t cost too much, vw said the sensors might be part of the valve body and will cost $2.5k so hopefully it is something cheaper...

the gearshifting solenoids are attached to the valve body.Their are eight solenoids.They sometimes go AWOL.
Have a trawl through here if you're interested,
Automatic Transmission Forum

They do not have T5's over in the US, the nearest similar gearbox designation is their 09G.Your gearbox is likely 09K.Similar gearbox, similar problems.

Try a search for 09G flaring or similar

[ImmortalT5]

Hey I took it to a transmission shop, very slowly due to constant rough gear changing and no power and getting stuck in 4th or 5th, felt like no gears were in gear completely,
They said a cylinder or something inside gearbox has blown and I also need a valve body so all up it will cost $5.5k-$6.5k to fix,
I am currently looking for a secondhand gearbox to put in instead and then the van might have to go...
gonna miss it...

[Tornado T5]

Sadly it's a common problem to T5 autos (it's actually a Japanese box). If you ever visit a dealer and mention you wish to trade it in on a new van the first question they will ask is "what's the transmission like"?

As you have been told the transmission was never included in the factory stipulated scheduled servicing. Mine went after I actually asked the dealer to service it and very soon after it made the flaring change and slammed into the next gear like I had been rammed from behind.

I could make it improve slightly by resetting the shift program as described in one of the tech section here put up by Transporter however eventually the dealer replaced it under warranty. It happened again on the replacement at around 250,000km and when it finally got bad enough I bought a new van from Renault...