How much does it cost to change an engine mount and a transmission mount on 1995 buick century, V6, 3.1L?

When should the engine mount and transmission be replaced on a 1995 Buick Century LTD, with a V6 engine (3.1L). Also, is one of the engine mount located on top of the engine and connected to the body of the car on top of the radiator? Also, much does it cost?|||I can't give you an accurate number of how much they cost, and there is no recommended time of replacement. They are replaced on demand/failure. The ones secured over the rad (I call them "dog bones") fail quite frequently and are easy to change. The transmission mount is a little harder to do and is required very seldom. The worst is the one under the front of the engine near the main pulley. All these cost not much, just labor.|||Lab is correct about the dog bones that are up top.The mount near the crank pulley usually needs Replacement due to oil leaking on it and the rubber breaks down.That one the cradle has to come down if not out and should be aligned.You only replace them if needed.If you are having a harsh shift check tranny fluid level.If you can get it to thump when power braking it is usually a mount.Do not power brake for longer than a couple of seconds and don't do it alot.Peace