The jerkiness issue aside, that's been reported by some launch owners, the root cause of which is yet to be formally ascertained(maybe it's the lifters as pointed to above), I don't think there's a cooling issue as such, it's the way the car has been designed with ecu managing it all. Why would you want the gearbox to be cooled upon startup rather than designing it to ensure it gets to optimum temp asap, same how engine cooling is designed.
Has there been any transmission, gearbox failure due to overheating, I don't think so. Has any touareg karked it whilst pulling a Bruderx(or a Jayco)? Nope.
So far it's temp anxiety rather than any performance issue, loss or degradation.
Is the jerkiness attributed to how gearbox cooling is designed I don't think so. My closest guess is mechatronic still, but I could be easily wrong as there's report above re lifters, valves being the issue. (Worth investigating if lifter part numbers have changed over the years)
The only change made in two years to the design of the CR related to cooling that I know of is the front side ports are open from my21.
Do we have enough information relating to this change for my21 vs my19 Touareg pulling the same weight to see if this makes a difference to temps I don't know.
So, from my perspective put aside temp anxiety and enjoy driving 😉
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