Hey,

If I have posted on this forum, it's been a while. I have a rattling noise coming from my '03 C4S (41k miles) and took it to the dealer to see what was up. I have an aftermarket warranty so I wasn't too concerned. After a brief look at the car, they told me one of my cats went bad (the rattling) and also the rear main seal had to be replaced. I'm leaking a very small amount of oil. After calling my shop in md (they do a lot of racing) I was told that the RMS is essentially an overhyped problem and I can wait until may, when I'm back in md to fix it. I really like this plan because I want to do a major clutch upgrade with lwfw and all and the shop told me they would do all of that and charge me zero labor because the the trans would already be out for the RMS (which is warranty. They also said they would replace my stock cats with 200 cel GT3 cats for free! I guess there is some sort of federal law on cats going bad. Anyways, does all this sound like a fine plan or should I have the rms fixed now?

 

You can wait on the RMS. I don't think the GT3 cats will fit the engine, unless I'm wrong, of course.

 

i would wait on the RMS until when you need a clutch or do you lfw. just for your information, i've heard that even the newest updated RMS seals still leak. you should look into a seal called Wrightwood Racing Rear Main Seal. lots of track people use this seal and its bullet proof

the GT3 cats def work since i use them too. they are bullet proof compared to the stock ones which i've had replaced quite a few times by the dealer too. i've never heard of a GT3 cat failing yet

sounds like you have a pretty good deal

 

Wow. Thanks for the advice. I am definitely going to look into the racing seal. Did you notice any gains on the GT3 cats?

 

i haven't done a dyno yet but it's def more free flowing, i think GT3 cats are 100 or 200 cell compared to the stock ones which are 400cell (don't quote me on those numbers, i could be wrong)