Power steering tensioner

Not sure. I'll take a look at mine later if I get a chance and let you know.

One important aspect is that a smaller pulley will spin significantly faster than a larger one. This translates to more wear and tear on the bearings and more heat. To calculate RPM for the pulley it's

(Crank pulley diameter/idler diameter) x engine RPM = idler rpm


If the tensioner itself is still in okay shape and it's just he bearing is bad, the bearing can be replaced. The unit came with NSK 6203 DU bearings installed. NSK bearings us th DU suffix in place of the more common RS suffix (rubber seal). A 6203 2RS bearing should work for the application, but it's important to buy good quality bearings and not cheap chinesium bearings. NSK, SKF, KOYO, NACHI, or TIMKEN are all sound choices. The NSK 6203 DU bearings have a limiting speed rating of 12000 RPM, so any replacement needs to be rated for at least that. I've got a couple of NSK 6203 2RS's waiting to go into the idlers on my Frontier at the moment. Just waiting on my new harmonic balancer so I can replace the timing chain seal (it's a 2.4L), and replace the valve stem seals all in one go.