Years ago I foolishly over-loaded a grain trailer-98,000# net-and, even stupider, in the dim light of pre-dawn, elected to park in the huge parking lot across from a coffee shop in Stanfield AZ. Huge mistake. It was actually a well cultivated, harvested cotton field, Nothing but powder a foot deep.
Only wrecker available was a small home-made type. When it showed up I nearly laughed. Compare to a GT trying to pull a CAT earth mover.
Tractor and trailer were heading back to the pavement when it bogged down, but a good 100 feet away.
"Don't worry, I'll get you out", driver said. "When my front axle hits the ground, that's all you've got."
He was right. Put a snatch block on my bumper, ran his cable out, winched it in...Lifting his front axle up about 5 feet.
Told me to use lowest gear and when I stopped moving that would be it. Not to try going any further.
Long story short, averaging 6,8-maybe 12 inches each time, it worked.
He only charged $50 for the 3 hour effort.
Bit off topic, but, a few will realize the point.
Patience...as long as there is a bit of movement, take your time and work it back and forth, ATF/acetone-as suggested by MNGB works and less cost than commercial products.