This bulletin applies to 2019-2022 Jeep Grand Cherokee vehicles equipped with a 5.7L V8 Hemi VVT engine.
A ticking noise may be heard from the exhaust manifold(s) when the engine is cold. Cracks may be present in the manifold castings. An updated exhaust manifold kit is available to correct the concern.
Start the engine cold. Listen for a ticking noise that stops after the engine warms up. Shut the engine off and allow to cool. Remove the exhaust manifold heat shield(s) from the side that is suspected to be leaking. Restart the cold engine and listen for the noise. Visually inspect for a cracked manifold and confirm that what you are seeing is not simply a casting parting line or casting fin. If a crack is found, replace the manifold(s). The updated manifolds are available as P/N 68591586AA (left) and 68591585AA (right kit for DS and DX vehicles) or right side for WK, WD and WL vehicles as P/N 68591591AA.
You will also need new fasteners (supplied in the kits). Replace all fasteners to prevent bottoming in the cylinder head. Fasteners were lengthened 6mm when tie bars were added to exhaust manifolds. Use all kit components for the repair (exhaust manifold, gasket, fasteners, heat shield and tie bar). Tie bars in the kit must be used even if there were no tie bars originally. Right side fastener 06510140AA (front-most fastener) is 5mm shorter than the other fasteners.
