Bad A/C clutch
 

Recently the A/C clutch on my 06 5.3l v8 trailblazer has started to go bad. It makes a awful clicking noise when it stops spinning. Is it possible to change just the clutch on the a/c or am I stuck with replacing the whole compressor assembly. If it is possible to change just the clutch can I buy them new or must I go to a junk yard and find one?

You can replace just the clutch, since you are asking, that tells me you should look at how big a job that is. Personally, I'd buy a reman compressor ready to install.

You can replace just the clutch but you have to be very careful not to damage the seals in the compressor. There is a special puller and installer to do the job.

Something like this?

That will work. here is the same one for $5.00 cheaper also at Amazon.