Depending on the date of manufacture, models have a two-piece harmonic balancer and pulley, or a one-piece combination of the two. Should the pulley hub be removed from the engine, a new retaining bolt has to be applied during assembly on which torque wrench of 302 ft-lbs / 410 Nm is to be applied. Initially, you can then remove the engine splash shields, viscous cooling fan/electric cooling fan and fan cowl assembly and drivebelts. It should be understood that there can be two types of external appearance of the harmonic balancer/pulley and hub: bolted two-piece and integral one-piece. In case of two-piece assembly, remove the retaining bolts that secure the harmonic balancer/pulley to the hub and lock the hub if required. Remove the small nut on the hub using the right tools to avoid causing harm or incurring too much loss, then pull out the hub from the crankshaft; if it is tight, use a puller to do so. To assemble the components and to dismantle the one-piece assembly, the following procedures should be followed: Before trying to remove the central bolt of the hub, the hub must be immobilized with specified tools; the same method has to be applied while withdrawing the hub. If the pulley hub has been pulled out, then it may be necessary to fit a new oil seal in the lower timing chain cover. If a Woodruff key is used, replace it and position the groove in the pulley hub over the key and slide it onto the crankshaft, then replace the washer and a new hub bolt. Torque the holding tool to the pulley hub and the hub bolt to the specified value for the two-piece assembly and replace the harmonic balancer/pulley with proper engagement of the locating dowel. For the one-piece assembly, secure the hub and fasten the bolt to the recommended torque. Last but not least, reset drivebelts, viscous cooling fan and cowl, and engine splash shields if any.