Repair-It

Yeah, seriously. I could blame the speedbump that I didn't see (used to be a gap during construction and I smacked it this morning at 18-20 mph). But I won't.

I noticed the exhaust seemed a little deeper than usual on the Caprice. I got to work and the right rear pipe had zero exhaust coming out. I looked under the car and it broke off right where it comes out of the muffler, before the pipe goes up and over the axle.

This annoys me because this is where my Dynomax exhaust failed, too. I went to Pypes because it was cheap and stainless but evidently, the over-the-axle pipes are just aluminized (you can tell if you examine them closely).

So what I'll have to do is see if I can procure another Pypes over-the-axle pipe. Then I will have to see if I can surgically remove the bit of pipe still in the muffler, expand the pipe and get the new pipe back in. Maybe I'll drive the CTS-V a bit. Unless the exhaust falls off.

Decided to take a few hours leave this afternoon.

I was a little worried about this, but it appears the pipe was in fact resting on the rear brake line. Fortunately, that brake line is both armored and stainless (aftermarket from ~2005 when I converted to rear discs) so I'm sure it's fine. But that doesn't mean I didn't cringe a little on every bump.

I got home and put it up on ramps to inspect. Conveniently, I used the 93 OEM style exhaust hanger so the muffler is very securely supported. You can also see how it broke. The driver's side is not far behind. The gnarly end of the pipe. Resting on the brake line. I decided I ought to at least remove the tail pipe. I couldn't finagle the pipe from around the axle so I had to jack the car up. I removed the band clamp thinking I could separate the axle pipe from the tail pipe but I didn't have to. After jacking the car up I was able to get the pipe out from under the car. By the way, the bolts on the band clamp were quite seized. I ended up having to use my electric HF impact. It took quite a lot of work to get them loose. Again, crediting my Craftsman sockets, I used a 1/2" drive 5/8" 6 point regular socket on the gun and it did not fail. If anything, I lately seem to be running into situations where this gun is not strong enough. One of these days I may need to try the pneumatic impact thing again.

After removing the pipe and seeing the securely hung passenger side muffler, I decided I will probably just drive the car like this until I can fix it. It's either that or drive the CTS-V. The horror!

But when I was done, I started the car, and it idled low and rough, then set a check engine light. See the new thread for more info. I love how this comes in waves.

Here is the system on the car now: http://pypesexhaust.com/i-12201000-94-9 ... sgi10.html
http://www.summitracing.com/parts/PYE-SGI10R/

I think I would have to call the company to get individual parts.

http://pypesexhaust.com/attachment/67601-SGI10.pdf

RockAuto sells the Walker (Dynomax) over-the-axle pipes for about $36/ea. I could examine some pictures to see if the dimensions look the same. I will say I believe the Dynomax pipes are mandrel bent better, where the Pypes pipes crush down around the tight radius over the axle. Not that my weak-ass L05 cares much at that...

http://www.rockauto.com/catalog/moreinf ... cc=1049699
http://www.rockauto.com/catalog/moreinf ... cc=1049699

I only bought this system 3-1/2 years ago. The rest of it seems fine, of course (which is 409 stainless). That was a better balance than the Dynomax system (which I also loved but had no crossover piping of any kind), which had polished 304 mufflers and tips (fancy), but everything else was aluminized (not fancy). I thought the Pypes system would all be 409, but the axle pipes still seem to be aluminized. Grrr.

Finally tackled this today.

Parts (linked previously):
Dynomax (Walker) right over the axle pipe, 2.5", P/N 54016
Dynomax (Walker) right over the axle pipe, 2.5", P/N 54017
Two 2.5" exhaust U-clamps from Napa

Step 1
Remove rusty shell from the muffler outlet. I knew this would be fun. It actually came apart in two pieces. For the inner layer, I jammed a flathead screwdriver between what I thought was the muffler pipe and the old over-the-axle pipe, and pried around until that shrunk the diameter enough to get loose. By the way, these Stanley plastic handle screwdrivers have been with me for like 20 years and they still take a beating with a 2.5lb sledge. Amazing.

Here is the inner layer from the other side: Once the inner layer is removed, it is revealed that there is ANOTHER layer of over-the-axle pipe. This one was the real award winner. I ended up using a combination of heat (which actually chipped away some of it without me doing anything other than torching), a cold chisel and the aforementioned sledge. Just had to chip away at it, piece by piece. By far the most annoying/longest part of this job.

This pic is the first I took, after I did everything I just mentioned: And on the other side, same deal. Step 2
Cut off the old exhaust clamp. I foolishly tried to wrench on the nut and twisted off one side of the clamp. Then I used a Dremel (when I have an angle grinder).

Step 2.5
Jack up car on this side

Step 3
Fit up the over-the-axle pipe. Won't slide over the axle until you jack the car up some to get the body up out of the way a bit.

Step 4
Install new clamp hardware, securing to exhaust hanger. Be sure to clock the pipe so it doesn't hit any number of items, including: upper control arm, gas tank heat shield, shock. It's extra important with these bigger than stock 2.5" pipes. Step 5
Remove tailpipe from old over-the-axle pipe. This was fun also. These pics are from the other side but the process is identical, obviously. A couple things made this possible.
First, my grandfather's vice which I finally installed a year ago. Second, a big ass pipe wrench that came with my house. Third, heat. You can see this wouldn't really just volunteer to separate itself... I wasn't kidding about the pipe wrench. And it isn't like you just press on it and everything twists apart. Like anything rusty, you have to press HARD and work it back and forth, little by little. I even took extra care to try changing up where the jaws press, because it was deforming the pipe just a little bit. I did get both apart with no damage.

Step 6
Install the tailpipe, setting the distance and orientation of the down turn spout. I reused that stainless band clamp that fought me back in Sept when I took it apart originally. Success! On the right side. Onto the left, which was getting pretty bad but may have gone another year before actually falling off.

I mixed some of the left pics in with the right actually. Here are some remaining ones.
Left over-the-axle pipe installed Left clamp Left band clamp to mate the over-the-axle pipe with the tailpipe. Same deal, but the right side. The finished product, basically. I guess I got used to the sound because this is MUCH better. Sounds quiet again (despite the "Race Pro" mufflers and no resonators). No drone. Very nice.

Wow, looks like that was a real PITA.. Not looking forward to doing this job...

I've done this at least twice now. I did it once with the Dynomax, and now once with the Pypes system. I really don't think I need resonators. You guys will have to hear it for yourself. I guess my tired old L05 doesn't bark much anymore.

kevm14 wrote:I've done this at least twice now. I did it once with the Dynomax, and now once with the Pypes system. I really don't think I need resonators. You guys will have to hear it for yourself. I guess my tired old L05 doesn't bark much anymore.

You will want resonators with an LT-1. Also, this job isn't bad if you are replacing all the parts. Which I would recommend since they are pretty cheap rather than separating rusty parts. I did the whole cat-back in the Caprice with the Pypes system in a couple hours.

It's quite a bit of savings to do just the over the axle pipes. The rest of it was fine, since I think it is some grade of stainless (409?).

I thought I'd throw this here. I heard a banging/clunking recently and noticed that the passenger side exhaust tip has been hanging lower than normal. It's actually been like that for quite a while (months?). Well very recently I noticed actual sounds. I decided to check (in the rain of course) and the tip was even lower than before. I moved it around and it was definitely banging on the body or wherever. I looked underneath and one of the tailpipe rubber mounts had fallen off. I slipped it back on (there are 2 total for each pipe in the rear) and it's fine now. Haha. That took me 30 seconds. Gotta love this car.

I could totally drive this to NJ and back.

Do it!!!!!!!!!!

Don't forget to bring the video camera...