Having the drive belts set at the correct tension is important for the best operation of belt-driven accessories and several adjustment gauges are sold, with instructions included with them. For measuring tension, fit the gauge into the center of the section you are testing, making certain it touches only the belt. While the routing diagrams shown for different engines follow the latest guide, using the Belt Routing Label in the engine box will help if you see anything that looks wrong. In left-hand drive vehicles, both belt tension and belt position are changed at the power steering pump bracket and idler pulley assembly. Firs disconnect the negative
Battery Cable, then loosen both the idler pulley bolt and the adjusting bolt. After assessing the pulleys, add a new belt and verify that its tension shows as correct according to the serpentine belt tension gauge after tightening the serial bolts and the idler pulley bolt, now at 47 Nm (35 ft. lbs.). Just like other engines, the first step for right-drive 4.0L models is to disconnect the negative battery cable. Then, you untighten the mounting bolts on both the lower and upper side of the alternator along with the adjusting bolt above. With pulley inspection done, fit and tighten a replacement belt, fasten all the bolts and test for proper tension on the belt.