ZD30 CRD Belt tensioner pulley.

[ausssiefan]

The bushes flog out and the shockie thingo loses its tension. The genuine bearing in those are double row and a stupid width too, you can't buy the exact same bearing. The aftermarket tensioners use a single row bearing, they work but wont last. Been down this road many times before. The best thing is to buy an OEM tensioner, and an aftermarket as a spare and keep this under the passenger seat.

Don't get me wrong - the bearing from WC87503 NTN is devinitly just a one row bearing, according to their homepage and drawings. Dimensions are ID 17 mm, OD 40 mm, total width 14.288 mm.