2004 Buick Century,what transmission?

hello everyone, i have a 2004 Century that i'm planning on changing the trans fluid and filter,what transmission did GM use in the 2004 Century? (think it was the 4T65E?) any helpful tips would also be welcome- torque specs for pan? fluid? filter seal?

It should have been delivered with the 4T65E. If you doubt this, look at the Alpha tag on the tailshaft/differential housing.

Despite what the owner's manual might advise, use only Dexron VI in the transmission. For a pan drop the refill will generally take about 6-7 quarts, but having an 8th on hand would not be a bad idea. Any parts store should have the appropriate filter.

When removing the pan it may be helpful for future service to install a drain plug, like this:

http://www.wwdsltd.com/files/4T65EPanPlug.jpg

The pan bolts should be torqued to 140 in/lb (about 11 ft/lb).

If at all possible, save and re-use the original pan gasket. It is a metal core gasket which is far superior to the cork or fiber gaskets supplied with filter kits. A new factory gasket is about $22 alone, but is worth it since they do not leak.

While the pan is removed inspect the cooling oil tubes to the differential and accumulators. Just be sure they are clean and not crushed or damaged.

thanks blue, very helpful!