Should I replace my Flex Pipe or get a Full Exhaust?

[evo_ski]

Hey guys,

So I have been searching around and it seems as though a Flex Pipe replacement will run me anywhere from $100-$200 depending on where I go, etc. Basically at this point I am trying to decide if I should replace that part or if I should just get a new exhaust to eliminate future problems down the road with mine. My car is a 1.8T Tiptronic with 88K on it and lived for a couple years in the mid-west, so it does have a bit of rust. So basically my questions is how long can I expect the rest of my stock exhaust to last given those details. It looks as though replacing a muffler, the parts will be around $250. I don't really want to spend the money on a full exhaust, but if my setup will cost me close to the same to maintain in the long run it might make sense to swap everything out now. I am fairly new to working on cars, so I don't know how much rust is normal, but here are some pics of my current exhaust.

Thanks in advance for the help.

Edit: For some reason my pictures wont add to this thread, but here are the pictures of my exhaust and the rust and everything on it.

http://img524.imageshack.us/g/img3696z.jpg/

[DrkBlueA4]

techtonics makes a downpipe for tiptronic. u can start off there
I made a mistake by buying the OEM downpipe which ran me around 300 so just get the techtonics and if u wanna do an exhaust down the road u already have a 2.5" downpipe

[John_JRP3]

Man thats some crazy rust. i just changed my entire exhaust with 100k on it and its like new.... if i didnt have a 6mt i would sell u my old.

[bigblue]

I'll sell you my stock tiptronic downpipe for $75 shipped... or you can buy a Techtonics tuning one for 280 like I did.

[Kittrell]

I would recommend replacing the entire exhaust at the same type. That is a ton of rust, it will make it extremely difficult to replace just one piece of pipe. You might have to cut it apart, those clamps might not even let loose with enough heat.

[walky_talky20]

Wow, this is kind of funny for me. I'm from PA, and that exhaust looks pretty decent to me. Around here, that kind of surface rust on the exhaust is completely normal. Those photos are by no means alarming. Mine looks just like that.

Anyway, the rust on the pipes is not the part to worried about. The part that will generally start leaking first is where the pipe meets the muffler, or where the exhaust mount brackets are welded to the pipes. That is where it could rust through. The OEM pipe, while it doesn't look like much, is very high quality pipe. Mine is original at 160k. A had to put a new flex in, but otherwise doing great. IMHO, etc.

If the junction between the pipe and resonator/muffler look questionable then I would say looking at an entire system could be worthwhile. The OEM muffler/resonator is quite expensive I'm sure. Weight is another consideration. The stock system is quite heavy. A mechanic should be able to give you a good idea whether your exhaust system is in trouble and whether fixing the flex would be worth it. He could easily check the condition of the rest of it to see if anything looks like an impending issue.

[Dan[FN]6262]

yeah, exactly ^^^^

that looks WAY better than my stock exhaust with 120k on it.

[jordon]

I gotta be honest.... It looks fine to me too. If you are trying to save a
few bucks right now, I would say just change the flex and I bet you will be fine for at least
a couple years.

[InfernaL]

I would say just save a few bucks and get a louder exhaust, such as magnaflow or something else. I got mine over the summer and mine didn't have that much rust, but it was still pretty bad.

[evo_ski]

Wow, thanks everyone for the quick responses. If I ever have a questions I can always find the answer searching on here. Do I run the risk of damaging anything driving it as is until I can get that replaced?

Thanks again everyone!

[Kittrell]

Do I run the risk of damaging anything driving it as is until I can get that replaced?

Not really, it'll be fine.

[InfernaL]

Not really, it'll be fine.

X2

[evo_ski]

Alright, thanks again everyone for the replies.

I just got around to getting it swapped out today. Took it in to Midas and they welded a new flex on there for me. The only thing is now when I boost over about 10-15PSI it makes a whistling noise that wasn't there before. Does that sound like it is a side effect of an improper welding job? Or is that going to be normal since now there is a new pipe in there and it has some different ridges and stuff on the inside of the exhaust that are causing the whistling since it is not just a clean one piece pipe anymore?

[walky_talky20]

How bad is it? I have seen that side-effect before from a replacement flex. It creates a weird noise at high flow rates. I believe it has to do with the inside surface of the flex being different than the OEM piece. I don't think it is terribly common, though. And I don't think it is anything to do with a poor weld job. It is unfortunate. You could take it back to them for them to check their work. There is a chance that is a leak. If not, perhaps they can give you a partial refund or something.

[playbak01]

I just realized I have an exhaust leak at the flex joint, so this post is timely for me. Dealer priced me the full downpipe/flexpipe (part# 8E0253301DR) at $340!!! I'm thinking f that. Is is possible to have a mechanic simply replace the flex joint? (see pic) Is that what evo-ski ended up doing?

[DownhillA4]

I just realized I have an exhaust leak at the flex joint, so this post is timely for me. Dealer priced me the full downpipe/flexpipe (part# 8E0253301DR) at $340!!! I'm thinking f that. Is is possible to have a mechanic simply replace the flex joint? (see pic) Is that what evo-ski ended up doing?

I too have an exhaust leak at the flex joint... I have yet to find a part number for solely changing the flex joint. Has anyone changed just the flex joint before or do you have to buy the entire OEM Downpipe?

OEM Downpipe... http://www.ecstuning.com/Audi-B6_A4-...Pipe/ES436590/

I have a 2004 A4 Tiptronic with Magnaflow 16601 exhaust, not really looking for more noise from an aftermarket downpipe.

[n7plus1]

1/4" more of pipe diameter isnt going to make that big of a difference in sound. From what i see/hear, the flex joints on these downpipes (b5's included) fail quite often. i would go the techtonics route and get a nicer part and a little tiny bit more flow.

[waldo1324]

My resonator is about to completely detatch from my pipes. Damn you stl winters.

[EYE4SPEED]

Would it be safe to say that the OEM one is slightly smaller than an aftermarket one (APR)? I need a new flex joint to mate to an APR exhaust - Quattro/Manual/1.8T.

[yung turbo]

i had my flex pipe leak too and just went to a muffler shop. they cut it off and welded a new SS flex on and called it a day. $40

[widgget]

the silver ring against the flex mesh in the photo below has rusted out and fallen off of the tttunning downpipe i have (4 years old + new england winters). going to get a new flex joint welded in rather then replace the whole thing.

[zjerunk]

I have a '02 A6 Avant 3.0L Quattro with 125K miles in pretty decent shape all round. I bought the car about 8 yrs ago w. 88K. I just broke one of the flex pipes (I'm not sure if they are O.E.) and I think the other is not far behind. The current flex pipes are "outer braid / inner interlock (like corrugated pipe)". The pipes, cats, and mufflers are in decent shape. The local mom & pop muffler shop I've used for about 25 yrs will happily cut & weld in their parts, but they also told me I could save a good chunk if I provide my parts because the labor is the same.

My supply source offers (1)"SS braid in & out," and (2)"Outer braid w/ inner interlock." Both styles are available with and without ends of different lengths. My shop prefers to weld the ends so they don't have undo fit issues if any.

Could someone tell me if the OE flexes are of the 1st or 2nd type, AND which is the preferred type for durability?

BTW, the shop says 2.25" inlet & outlet ID X 4.0" long flexes (the given flex sizes are always the ID).
Do these comport with the OE pipes? I don"t want to order the wrong size flexes.

Any help would be appreciated. Thanks.

[ADCS]

Neither style are preferred IMO.

The corrugated inner liner is bad for flow. The braided inner liners are prone to breaking apart and clogging... assuming the corrugated part lasts long enough for that to happen.

The ideal solution is something like the TurboFlex flex pipe by Vibrant Performance. All stainless and they have a smooth inner liner for optimal flow and no chance of clogs.