Hi, I just purchased my first MB...an '04 SLK320. Yea, I know, the SLK350 will be out "soon", but I like the look of the '320, and what to heck...I can drive it now & got a decent deal. I've got a lot of audio system questions...anyone that's replaced the head unit in a 2003-2004 SLK, I'd like to hear from you!

Bob

 

Does your car have a Bose or other "special extra cost system," if so it might be very difficult to replace the head unit, as these units are connected to a amp or amps according to the system and then to the speakers, I'd say your best bet would be to upgrade the speaker system. I have a Bose system and ran into this situation, the head unit really doesn't produce a better sound, the amps and speakers are the key elements to the sound reproduction. By the way I kept mine stock and added a sub to the trunk and had a grille place in the space were the back armrest folds down, my car didn't come with a pass thru the trunk, Improve the quality of the sound 80%.

 

Actually, what I'd really like to do is replace the head unit with an Alpine head unit featuring a built-in XM tuner and a single-disc CD (and ditch the trunk-mounted changer). I'd like to use the existing amp & speakers if possible.

 

Shouldn't be too much of a problem, if you keep the stock speakers and amps. Your new Alpine head unit, will use the same 1 vpp signal for the pre amp output as the stock head unit. all of the speakers connect to the amps, so no modifications will be necessary there. If you're not too handy or don't have much in the way of electical tools (wire gague stippers, butt splice connectors, etc.), I would say take it to a pro. Plus, if anything happens to break or blow up... it's on them not you!