Q: How to remove and reinstall exhaust manifolds in V8 engine for the 2008 Toyota Tundra?
A: For 2UZ-FE engines, start by disconnecting the cable from the negative battery terminal, then remove the heat shields from the exhaust manifolds and disconnect the oxygen sensor wiring. Apply penetrating oil to the exhaust manifold and exhaust flange fasteners, allowing it to soak in before removing the exhaust pipe flange nuts and unbolting the exhaust manifolds from the cylinder heads. For 1UR-FE, 3UR-FE, and 3UR-FBE engines, remove the exhaust pipe flange nuts and lower the exhaust pipe, then take out the lower engine splash shield to access components underneath. Drain the engine coolant, remove the engine cover, air filter housing, drivebelt, upper and lower radiator hoses, and the fan shroud. Take off the inner fender seal and wheel housing splash shield from the side of the manifold being removed. For the right side manifold, remove the engine oil dipstick tube, power steering pump, alternator, heat shield fasteners, and the exhaust manifold nuts along with the manifold and gaskets. For the left side manifold, remove the A/C compressor and place it aside, then for 4WD models, remove the front driveshaft and its heat shield. Make aligning marks and disconnect the steering coupler, followed by removing the heat shield fasteners and the exhaust manifold nuts. Inspect all manifolds and fasteners for cracks and damage, then use a scraper to eliminate old gasket material and carbon deposits from the mating surfaces. Check for warpage if the gasket was leaking, and resurface if necessary. Position new gaskets over the cylinder head studs, install the manifolds, and thread the mounting nuts into place. Tighten the nuts to the specified torque in three or four equal steps, then reinstall the remaining parts in reverse order, using new gaskets for the exhaust pipes. Finally, run the engine and check for exhaust leaks.