You don't need wheel spin to go from off-road height to extended height. If you want to test it it is easy:
Park on a firm ground (parking lot, driveway) Leave engine running.
Put it in Off-road Height
Put an axle stand or Jack under crossmember under the gearbox.
You can then or jack it up and it will go in extended mode or you can select normal height and then the D3 will try to lower and senses that it bottums out and will raise to extended mode.
I cannot get my 2005 manual into super extended mode. I tried severall times.
If have had very high stands after being recovered.
If you get stuck and dig in on a steep soft sand hill the D3 will go in extended mode. If you then get recovered backwards by pulling you D3 up you will get additional clearance.
Roel
BN55 WPT G4 D3 LHD Team Greece. Now on Dutch license. 1984 TD5 90 Camel to be
P101JWK 1997 CT Disco Now in the Dutch Camel Trophy Museum.