"If you miss the off-ramp, just pull over and reverse back," the TikToker posted alongside the video.
The video shows the grey car waiting for a gap on the lane while slowly reversing onto the motorway hard shoulder, then speeding down the off-ramp.
The driver has to stop a few times as other vehicles, including trucks, drive down the lane.
According to the TikToker who uploaded the footage, the incident happened on Tuesday morning, near the Westgate motorway exit, in West Auckland.
"I recorded the whole thing. Took her about three minutes, which she could have used to get off at Brigham and come back round," the TikTok user said in a comment, referring to the Brigham Creek Rd off-ramp further along on the same motorway.
A number of TikTok users wondered how many people would do this, if they knew they weren't being watched.
"God, that is dangerous, although I'd probably do the same if it was super quiet," one person commented.
Another person said they've "lost count" of the amount of times they've witnessed similar risky manoeuvres.
Poor driving behaviour should be reported to police by ringing *555.