4.7 inline radiator fitting
The OEM one is plastic and the one at www.rockauto.com is a direct OEM replacement (plastic). The aluminum one is more durable and a better replacement not to mention transferring from a 1 piece hose to a 3 piece for easy replacement of hoses and such.
The upper radiator hose for the 2000-2003 Durango 5.9L the is bigger than the one you listed in diameter. The upper radiator hose on the 2000-2003 Durango 5.9L is 1 15/16 inch and the other one is 1 15/32 inch. The 2000-2003 Durango 4.7L (the years it the 4.7L were produced) are 1 1/2 inch which are smaller and so this aluminum direct replacement neck you suggested will only work on the 2000-2003 Durango 4.7L and not on the 5.9L.
The 1998-1999 Durango 5.9L has 1 15/32 upper radiator hose. 1998-1999 Durango 5.9L doesn't have this neck at all (1 piece hose) and was built with a regular radiator and regular cap being on the radiator. The cap is 16 psi OEM








