Want to upgrade exhaust system on 03 CLK 500, need advice
Thanks
One of my secondary cats detached and was spinning in the housing. I just had a shop cut it out and weld in a test pipe. It was <$100 and gave it a bit more grunt. No considerable power increase tho.
If its a primary cat, thats a little different. Do you have to do emission testing?
The secondary cats are after the emissions O2 sensors, so the secondaries can be cut out without any emissions issues or CEL.
I am trying to be honest, I like these cars a lot, but save up a good amount for repairs because they will be needed. Drive it stock and try to keep up for as long as possible is my advice.
Not worth shelling cash on custom pipes now, then realize in a few months that your car is in limp home mode and needs a new transmission.
1. The crankshaft position sensor is $50-100 at Napa, and although its not the easiest job ive ever done, its hardly anything you would need a mechanic for. One electrical connection, one screw, and a little bit of blind working.
2. There is no issue with balance shafts for the CLK500 which has the M113, its a mostly bulletproof motor. Thats the v6 and the newer v8 that have that issues.
3. The transmission control plate does sometimes need to be replaced. Yeah, it sucks. But you can go on ebay and get kits for $75-200 for the plate and gaskets.
The 03 clk was pretty stout overall. It does have some issues, but if you are a DIYer, these are not all that expensive of a car to work on.
Get the test pipes welded in, you will not regret it!


