Should you change the transmission fluid if you missed the original change mileage?

We have a 2006 Jetta GLI with the DSG gear box and it appears that the car shop that did the 40K service did not change the transmission fluid. Now at 70K miles, a different car shop mentions that the car sounds a bit rough and suspects the transmission but the car appears to shift fine. He states that he does not recommend changing the transmission fluid at this later time because he has seen the transmission fail and other problems as a result. Should we get the transmission fluid changed or has the ship sailed and we should drive it and cross our fingers.

Yes, the fluid should be changed about every 30k miles and no harm will be done by this. That’s an old wives tale.
This tale originates from the fact that many people change the fluid after suspecting a transmission problem. The problem becomes worse and they mistakenly blame any ensuing transmission problem on the fluid change.

Whether this has anything to do with the car sounding rough I have no idea. You might clear that phrase up a bit by providing the exact symptoms.

Whether the first shop is at fault is unknown. That depends on what they were asked to do.

Look at the transmission fluid the same way as the engine oil. Because transmission fluid is just straight 10 weight oil with the proper additives. If you miss an oil change on the engine do you just not change the oil and filter and cross your fingers? No! You change the oil and filter. The same holds true with the transmission fluid.

Tester

That old wife’s tale about changing the fluid causing a failure is just a result of all the drivers who don’t get their fluid changed until they start getting a problem. By then it is too late and the transmission is about to fail no matter what you do. However it is not failing because it gets changed, it is failing because it was not changed when it should have been.

The real shame here is all the manufacturers who are not listing regular fluid changes as part of their recommended maintenance.