I've got a 05 sedan with sirius. Is it possible to change out the module in the trunk to get Xm, or is it more involved?

 

Your also going to have to change the antenna. Running the antenna wire is the labor intense part; you may be able to cut it and splice on the XM antenna, but why switch? The differences are marginal... You would probably realize that a switch is wasted money after you go through with it..

 

well, I've got XM in my silverado and I like the stations much better (no cheesy dj's, etc.) But you're right, its probably not worth it.

 

Find someone who wants to trade their XM for Sirius... Or eBay.

Changing the antenna is not a big deal. It runs around the rear window and into the trunk under a little tape and a seal. Whooopie. I put a mini XM antenna on my G in the normal spot in about 10 minutes. And I had to dremel the notch on the lip of the trunk opening under the seal. His will already be done.

This is a breeze. The harder part will be finding the XM receiver at a reasonable price or fair swap.

I can tell you it would be very worthwhile for me if I were you. I strongly prefer XM (as a one-time subscriber to both).

 

FYI,

Do not attempt to splice into the XM/Sirius antenna wire, It has similar properties to a coax connection.