Motor mounts are metal mounts with rubber inserts that keep the engine in place under heavy torque. When these mounts go bad it can be loud and potentially cause damage to other components of your GMC. Replacing a motor mount in most GMCs is relatively straightforward if you have the proper steps outlined to complete the task. You will also need just a few tips to avoid additional work during the repair.
Jack up the front of your GMC and secure it with jack stands.
Bolt the engine hoist to four solid points on the engine, two in the front and two in the rear. Exhaust manifold bolts make good mounting points.
Jack up the engine hoist until the chains have no more slack in them.
Locate the motor mounts under the engine. They will be on both the left and right sides of the engine. They are metal pieces with rubber inserts that bolt the engine to the frame.
Remove the center bolt from the motor mount using a ratchet and socket. Raise the engine hoist about another inch or two freeing the engine from the mount on the frame.
Loosen the bolts securing the motor mount to the engine. Place the new mount where the old one came off and tighten the bolts until secure.
Slowly lower the engine hoist until the hole in the mount on the engine lines up with the mount on the frame. This may take several attempts to line up properly.
Push the bolt through the center of the mount, once it is lined up. Tighten the bolt until it is secure.
Repeat steps two through eight for the motor mount on the opposite side of the engine.
Lower the vehicle and test-drive it to make certain there are no noises from the new mount.
