6 speeds automatic trans.

I can't speak for having this capability in a minivan, but do know that the "auto-stick", which allowed manual shifts of the electronically controlled

4-speed automatic transmission on my 1996 Eagle Vision TSI, was a wonderful feature. I used it regularly every winter to compensate for the low 1st gear and high torque engine which used to result in simply spinning the wheels whenever trying to start from a dead stop on snow/glare ice. By starting in 2nd or even 3rd gear, I was able to simply pull away (rather slowly) without spinning or sliding on ice.

Other than this application, I also occasionally used the manual gear control to downshift into lower gears and provide some engine braking when descending steep declines.

Hope this is what you were looking for from your question.

Bob

When climbing a twisty mountain road, I dropped my trans from "D" into "3" to prevent it from shifting up into overdrive every time I lifted my foot off the gas for another hairpin turn. When the slope got steep enough, I even put it into "2". The reason for a shift selector on an automatic is to be able to override it for particular needs or performance.

Also, if you're slowing because, say, the car in front of you is turning, you can downshift and be in a lower gear for acceleration before putting your foot back on the accelerator, and thus before the tranny will downshift on its own. That's what I used to use mine for primarily.

Same reason you'd shift a 1969 3-speed automatic manually from time to time- in situations where you need more control.

Driving down a mountain road to utilize engine braking rather than wear out the brakes. Driving up a mountain road to minimize "hunting" between gears. Holding it in a lower gear as you approach a freeway onramp so that you can jump in to traffic at maximum acceleration without waiting for the transmission to figure out that it needs to downshift. Starting up on an icy road in 2nd gear so that you minimize wheelspin. Etc. etc. etc. etc.