Catalytic converter and trans fluid questions

[Mnaveo]

2008 aveo sedan 196,xxx miles and counting.

I will be ordering parts for my car soon.
One the list is a front pipe/flex pipe as mine is no longer doing its job. Along with it a catylatic converter.
A shop wants to charge $300 just to weld in a newflex pipe. Rockauto has the whole pipe for around $100. And ive found it cheaper yet on ebay or amazon.

As far as the cat, i dont want to spend $300-$400 on it. Ive found some for $100 or less again on Amazon and ebay. Will these cheaper ones work?
For those who have replaced theirs, what did you use?


I want to do a trans fluid change. The fluid is pretty dark/dirty.
I know the fluid is t-IV. What is complatable? The previous owner used royal purple. Ive seen something about valvoline maxlife and Castro being used.
Should I just use royal purple like he did?

[avguy]

Are you going to DIY the exhaust job, or will you take the parts to a shop and have them do the install? If you're going to DIY, do you weld?

I bought a cat last year for my '05 on Ebay for around $100, to eliminate a P0420, which has been working fine with no CEL or other issues. The flange welding was not the best, but that apparently does not affect performance or durability of the cat.

You can spend more for Royal Purple transmission fluid, or buy the the less expensive Maxlife, which many of us have used, and which works perfectly well. The Castrol fluid probably is fine also, although I haven't used it myself.

[Mnaveo]

Thanks for the reply.

I'd like to do it myself since the front pipe/flex pipe bolts in as does the cat.
No welding for this guy. But i did see a welding kit for home use that i want that may change that.

Which valvoline maxlife should i use?

I read the back of the valvoline maxlife atf bottle. It doesnt say anything about gm's t-IV fluid. But it lists Toyota t-iv. Are these two in anyway similar?
Ive seen the Toyota fluid mentioned on here a few times i believe.

[avguy]

.... I'd like to do it myself since the front pipe/flex pipe bolts in as does the cat.
No welding for this guy. But i did see a welding kit for home use thst i want that may change that. ....

I suggest that you take a close look at of the exhaust component connecting bolts. On both of our Aveos ('05 and '06), all of the bolts (except the manifold-to-cat bolts) were rusted to the point of being unrecognizable. And to make matters much worse, after grinding off the rusted bolt stubs and separating the flanges, there remains the task of drilling the bolt stems out of the flange.

I first replaced just the muffler on my '05, due to the short connector pipe being rusted out. I don't weld either, and getting holes drilled into the mid pipe flange was a nightmare, due to the constricted working space underneath the vehicle. Later I had to replace the rest of the pipes, and learned my lesson from that experience. When it came time the following year to do the '06 exhaust, I replaced the entire exhaust system in one job. I can tell you that it was SO MUCH easier to just cut apart the old pipes and then install all new pipes and the muffler.

I would expect your '08 to be in similar condition rust-wise, unless they substantially improved the connecting bolts. So if they're rusted, I highly recommend that you consider doing the entire system at the same time, unless you want to try getting into welding (which I'm sure would be a great alternative for those who weld).

.... Which valvoline maxlife should i use? Dex/merc atf or dex 3?

I'm only aware of one flavor of Maxlife (suitable for Aveo transmissions), unless something has changed since I last bought it.

[Mnaveo]

Avguy, thanks for the reply and insight into the exhaust idea. Truth be told, ive been toying with the idea of replacing the whole system. In the rear it almost looks like the exhaust was for a hatchback and not the sedan. The previous owner had to add to the tail pipe to extend it all of the way back.
I wanted to do a muffler delete since I read that's the biggest restriction in the system (someone correct me if I'm wrong).
Depending on the cost, I may take your advice. $300 to replace just the flex seemed pretty steep to me.
If you dont mind, ball park, what did it cost to replace the whole system?
Where did you get your parts from?

If it makes life a little easier, it may be worth it. Less cussing, swearing, and frustration. The exhaust doesn't look to be in very good condition to begin with.
If there was a "perfomance" or some sort of improved exhaust system, I'd definitely be seriously considering it. But I havent seen any.

[avguy]

I've used only Walker pipes and mufflers via Rockauto, and when I last bought them, the 2 pipes, muffler, gaskets, and stainless bolts were around $250 total. As I already mentioned, the one cat I bought was from Ebay for around $100 (no-name of course). Walker exhaust parts have been a mixed bag for me. On the plus side, they fit exceptionally well in all respects - perfect actually. But on the minus side, they are not built to have an extend life. The first muffler on my '05 rusted out in just 3 years. Walker did replace it under lifetime warranty with no questions asked, but I suspect that 3-4 years is about all that anyone living in the rust belt can expect from both the muffler and the pipes (the pipes have no extended warranty). So if you definitely plan on keeping your vehicle much longer than that, you might want to consider other (i.e. more expensive) exhaust parts, if they give a longer warranty on the pipes. I'm an old geezer who doesn't mod, so I can't help you on the question about the muffler delete.

[Mnaveo]

Avguy, thank you for the reply. I appreciate the info on exhaust. Thats not bad really. I was expecting it to cost more.
I honestly like this little car. It's not fast by any means. But it's very dependable. Dependability beats speed/performance in my book. At least when it my only car.
I'd like to keep it for a while for sure. Ive found it to be pretty easy to work on so far. Much easier than my ford focus.
Here in Minnesota, cars don't last long before the rust sets in. I've seen some trucks thwt arent even 10 years old with severely rotted out cab corners and rear wheel wells.
I wouldn't expect the exhaust/mufflers to last any longer than you said. Regardless of price.