When in auto mode I'll experience a "slam" in the drivetrain as the transmission is commanded to downshift from 6th to 5th or 5th to 4th. It usually doesn't need to downshift but all parameters must request it. It's not all the time but garaunteed on most drives. Any similar symptoms? I know valve bodies are notorious for replacement.
In manual mode allows you to get off the throttle before the downshift ensuring a proper and smooth shift. If under a load in auto if it decides to downshift it is extremely harsh.

 

I get this on occasion, since I bought my used 2005 Turbo on Friday. I chalked it up to standard/common VW transmission personality.. My VW Jetta did the same thing, once in a great while.. These do use the AISIN 6-speed transmissions, pretty sure are also the exact sameunit in the V10 TDI Touareg. If there is a fix or updated Valve Body, that would be nice to know..

I believe the model designation is the "TR-60SN" for our transmissions. I wonder if there are any upgrades to these..

 

My research of the transmission in our vehicles is an AISIN TR-60SN Also known as the 09D VW Part, is used in the First generation VW Touareg, Porsche Cayenne, Audi Q7 (Volkswagen transmission code: 09D)

Here are a few options for those of us brave enough to disassemble the bottom of the transmission (assuming everything else is happy in the unit)

https://revmaxconverters.com/product...ed-valve-body/

https://www.oregonperformancetransmi...TR60SN-RB.html

https://www.sonnax.com/tech_resource...-09d-solutions


Some other information for the Touareg guys but likely applies to us (seeing as it's the same chassis & gearbox)

https://www.clubtouareg.com/threads/...ed-yet.285263/