Did you check the fluid level? Sometimes low fluid will cause the pump to cavitate and then you lose hydraulic pressure and the trans goes into neutral. Letting it sit for a bit allows time for the fluid to drain back, refill the pan and then you start the whole process over again when you drive for a bit.
1994 FZJ80. Elocked, MAF 3/2 Lift, BFG 315 KM2s, stock 4.10s, ARB bullbar and a Warn 8074 winch.
powered by an all-aluminum 335hp L33 Vortec V8
2004 Kona Stinky dee-lux.