A series of numerical model experiments are studied with a view to determine whether the chlorofluorocarbon (CFC) burden in the North Atlantic Deep Western Boundary Current (DWBC) can be simulated realistically in models of coarse horizontal resolution. Five main model cases are considered, covering three different parameterizations of subgrid-scale mixing (standard Cartesian, isopycnal, and the eddy advection scheme of Gent et al. <1995>), a version with enhanced surface thermohaline forcing, and, finally, a case that incorporates the effects of topographic stress as in Alvarez et al. <1994>. Most model experiments exhibit deficient CFC content in the DWBC, except, notably, the case with a tightly constrained wintertime thermohaline forcing in the North Atlantic, as well as the run which includes the effects of topographic stress. However, the approach of strongly restoring surface temperature-salinity to observations yields excessive heat loss and large freshwater fluxes during winter and so cannot be recommended as a technique to rectify deficient North Atlantic Deep Water production in ocean models. Overall, the coarse-resolution simulations only resolve a relatively weak and diffuse CFC signal in the DWBC in the North Atlantic and typically only capture one CFC-bearing core. This is primarily due to model currents in the deep North Atlantic being too slow and broad compared to the real ocean, as well as a spurious tendency for the outflow to recirculate and upwell into the Gulf Stream. The model runs do not capture a deeper CFC core because they all fail to simulate a dense water overflow off the Greenland-Iceland-Scotland Ridge. Seawater age is analysed in each of the experiments using an idealized age tracer as well as the simulated CFC-11/CFC-12 ratio. The CFC ratio estimates water in the DWBC at the equator to be between 25 and 33 years old. In contrast, the equilibrated age tracer ranges from 141 to 210 years. The CFC-estimated age is substantially younger than the true seawater age because of a mixing bias when CFC-free waters are entrained into the DWBC. This is possible because old CFC-free waters cannot alter the CFC-11/CFC-12 ratio of CFC-burdened water, even though the true age is affected by such a dilution. It is therefore suggested that caution be taken when adopting the CFC-11/CFC-12 ratio to extrapolate seawater age in waters where significant dilution with CFC-free waters has occurred. ¿ 1998 American Geophysical Union