It can be done. Chevrolet tried in the early 60's with an expedition of early Corvairs. They failed. The Corvairs are in the jungle. Then in the 70's a British expedition set out with the new model Range Rovers. They made it although they had lots of troubles with axles breaking on the Range Rovers and bought an old Land Rover in Central America which made it through best.
Range Rover Darien Gap - Range Rover Classic

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13