If you want to avoid wet belt engines, where the cambelt runs within the oil, then your best options are the Renault Kangoo 1.5 dCi, Nissan Kubistar 1.5 or the VW Caddy 2.0 TDI, each of which are a similar size to the Ford Transit Connect but which use a dry belt engine. Depending on how old a van you are looking for, the previous generation Vauxhall Combo and Fiat Doblo don't have a belt at all, but use a timing chain.