OEM GMC Sierra 1500 Classic Timing Chain

GMC Sierra 1500 Classic Timing Chain Parts Questions & Experts Answers

• Timing Chain
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  Q: What tools are required to replace the timing chain, sprockets, or tensioner on GMC Sierra 1500 Classic?

  A: To replace the Timing Chain, sprockets, or tensioner, the following tools are required: rear pinion bearing race installer (J 5590) and Crankshaft gear remover (J 5825-A). The first step is to remove the Crankshaft position (CKP) sensor reluctor ring while installing a 7/16-20 x 1 inch bolt into the end of the Crankshaft. First align all marks then remove the Timing Chain when the number 4 cylinder reaches its compression stroke at top dead center (TDC). Disengage the Timing Chain tensioner shoe from its pin before removing the camshaft sprocket bolts and extracting the camshaft sprocket with its attached Timing Chain. Use a Crankshaft gear remover tool (J 5825-A) combined with an open-end wrench to remove the Crankshaft sprocket followed by this operation with the Crankshaft balancer key. Proceed with Timing Chain tensioner bracket bolt removal if essential before cleaning and inspecting the Timing Chain system with its sprockets. Proceed to install the Timing Chain tensioner bracket and bolt while torqueing the bolt to 12 nm (106 inch lbs.). Align the Crankshaft balancer key with the sprocket keyway while keeping the key in the Crankshaft keyway either parallel or tilted slightly. Use the rear pinion bearing race installer (J 5590) to put the Crankshaft sprocket into place. The camshaft sprocket needs installation with its alignment mark facing the 6 o'clock position while the Timing Chain surrounds the Crankshaft sprocket to place it towards the driver side of the engine. The Timing Chain tensioner shoe should be placed under the tab on the bracket top before inserting the camshaft Timing Chain sprocket into the chain as you verify that the camshaft marks align with each other for final placement. The installation of the camshaft sprocket must be done without a hammer tool because hammer strikes can displace the expansion cup plug. Install the camshaft sprocket bolts, tightening them to 25 nm (18 ft. Lbs.)adjust the Crankshaft sprocket to sit at the 12 o'clock position when the camshaft sprocket rests at the 6 o'clock position. End your installation by removing the Crankshaft bolt to add and secure the ckp sensor reluctor ring.