Just had a look myself, the Transit Custom is a new design of midsize van that sits between the smaller Transit Connect & the bigger Transit.
Payload of the new 2012 Transit Custom is between 600 & 1400kg depending on which version you pick, 2 different wheel base options & there are 3 versions of the 2.2 TDCi diesel engine with the most powerful having 153 bhp.
Again there is info on the Ford UK website - head for the Commercial vehicles section, no idea which versions will end up for sale in the US.
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