Q: How to replace engine mounts for Chevrolet Avalanche,Silverado,Suburban,Tahoe,GMC Sierra,Yukon,Yukon Denali,Yukon XL?
A: Engine mounts rarely need attention, but if they are broken or deteriorated, they should be replaced immediately to prevent added strain on the driveline components, which could cause damage. During the check, the engine must be slightly raised to remove the weight from the mounts. The vehicle should be raised and supported securely on jackstands. The mounts should be checked for cracked, hardened, or separated rubber from the metal plates. Relative movement between the mount plates and the engine or frame should be checked. If movement is noted, the lightness of the mount fasteners should be checked before condemning the mounts. Broken engine mounts are usually very obvious as the engine will easily move away from the mount when pried or under load. To replace the mounts, disconnect the cable from the negative terminal of the battery, raise the vehicle and support it securely on jackstands. On 4WD models, remove the interfering driveaxle. If working on the left mount, it may be necessary to remove the left inner fender splash shield and the exhaust manifold heat shield on most models. Remove the engine mount-to-frame bracket bolts. Attach an engine hoist to the top of the engine for lifting. Do not use a jack under the oil pan to support the entire weight of the engine or the oil pump pick-up could be damaged. If a hoist is not available, a jack can be placed under the large casting lugs on each side of the engine block at the rear to support the weight of the engine while the engine mounts are being replaced. Unbolt the mount from the engine block, then raise the engine far enough to remove the mount from between the engine and the frame. Installation is the reverse of removal. Use non-hardening thread locking compound on the mount bolts and be sure to tighten them to the correct torque specifications.