Anyone having problems with their aftermarket exhaust causing things to melt underneath their car??

Okay hears my problem-- I was driving one day... all of a sudden I smell something burning. My car starts filling up w/ smoke. I look for somewhere to pull over, and of course I start catching every light. I stop at a red light, then it turns green and I start moving. I hit the gas and move about 3 feet and BOOM, CLANG, CRASH, and the car stops moving. I push the car to the side of the road, call up my buddy who brings a 3ton jack and some jackstands, and we take a look under the car.

Okay... so now a small chunk of my zero gauge power line is burnt (even though it didnt hit the exhaust pipes)... and My freaking driveshaft is snapped in two! Also, the lines to my ebrake are all melted.

I took the car to Nissan to replace the driveshaft (and they also replaced the tranny cause I had a synchro problem) under warranty and they did. When I came to pick the car up, they put it on the lift to show me what they thought cause the problem, and they said they thought it was my aftermarket catback and cats (Stillen and Crawford).

>>>They said the excessive heat generated by the cats and the catback, and the lack of heatshields on them, is what caused the driveshaft to go. Being the the Z driveshaft is made of carbon fibre, it is much more sensitive than others they said, and it also melted all of the brake lines down there. Has anyone else experience the same or similar experiences w/ their catback or are the Nissan techs BSing me?? It seems odd that Ive had the exhaust stuff on for several thousand miles and the ebrake lines, the chunk of zero gauge, and the driveshaft all went simultaneously if it was from the exhaust.

 

hmm odd

i'm sure there's people out there with that same setup with thousands and thousands of miles and no problems though

who knows

dealers usually will do anything to BS their way out of covering something though

if they're making you pay for it, then try to fight them on it and prove that your aftermarket parts caused it - make them work for their excuse. Otherwise they're really just guessing aren't they?

 

That's scary and concerning...

I'm getting ready to upgrade my entire exhaust system and have had these exact concerns. Seriously... I was already thinking of a ways to fabricate heat shields out of a bunch of flat aluminum scrap I have on hand. I was also thinking of JETHOT coating everything, ie SS headers and possibly TP and just keeping the stock exhaust for now until more research is done on the perfect setup.

I’m glad you didn’t hit the fuel line...yikes!!!

 

I would think the opposite. With the hi-flo parts in place things would be cooler. Maybe not. Anyway don't the Crawford cats have heat shields????? I thought from pics it looks like they do. Although now you have me thinking about my Helix hi-flo cats. They are SS and have no heat shields.

 

Nah I had to fight with the techs for a little while, but they gave in and covered it under warranty. Get this though- they charged me an extra 150 bucks out of pocket cause they said my exhaust system was "complicated" and created extra work for them.

I called up Stillen today and they said theyve never heard of a problem like that with the driveshaft as a result of the exhaust system, and theyve sold thousands.

 

Did you use the right donut hanger to mount the exhaust on?

 

I'm not really sure what to think at this point... If you look at a pic of the OEM exhaust system and a Stillen or Borla in comparison, the center most pipes surrounding the CF driveshaft area are not covered. I would believe at times tremendous amounts of heat coming off those parts. But you would think with the air rushing over those parts it would not be a concern, I guess that is if your not in stop and go traffic and showing off by reving the engine multiple times. YES, you would think these guys tested their systems for thousands of miles in desert heat and WOT. I hope...I'm sure for liability reasons...

I’m pretty sure I remember reading HELIX’s description that the CANS had thermal barriers. Again, all liability reasons.

 

Not that I would ever trust the Stillen sales dudes regarding issues that they have heard of... regardless - I have 19K on Stillen Cat Back Pipes - no issues at all. They still sound as smooth as when I first started driving my ride.

 

Good to know, because it's one of my choices for an exhaust And that concludes our real world testing.


I still can't believe his drive shaft broke in two!!!!

 

Heh, whats actually kind of funny is that I was afraid that the Nissan techs wouldnt cover my tranny under warranty with my short shifter in, so right there on the side of the road, I put a wedge behind my rear tires (because my driveshaft was snapped so putting my car in gear did nothing, and my ebrake lines wear cooked no no brake either) and then had my friend drive me home to pickup some tools and my stock shifter.
Then, right there on the side of the road, we actually jacked the car up and changed out the short shifter. He even snapped a pic of the shaft snapped in two on his camera phone, but you know camera phones, plus there wasnt much light under the car, so it didnt come out too good.
But while I was working under there, my hands were right on the thing, and I can definately testify that the thing was snapped in two. It was all splintered and everything, and then the snapped piece went in an irregular spinning motion after it snapped and thats what took the chunk out of my zero gauge.

Oh yeah--- hahaha forgot to mention this little coment about the quality of Nissan techs- When I first dropped the car off they made their initial scan of the car, and the tech reported to me that the problem with the car was that my clutch was burned out, and thats what caused all of the smoke. I asked him if he saw the snapped driveshaft and he was clueless and kept arguing with me that my clutch caused all of the problems. He confessed to me that he couldnt see the driveshaft because they were examining from above the car. A transmission assessment from above the car??
Regardless after they put the car on the lift the guy called me back with an "oh yeah youre right" attitude. Today I get the car back-- he never changed the clutch, it ended up being fine when they looked it at it up close.

 

Just a though here.
Maybe you got a bum drive shaft from the factory and when it let go it took the stuff around it out too. CF is a great drive shaft material but if there are imperfections during manufacture, it can seriously degrade the strength and longevity, especially if it causes it to go out of balance.

Another possibility is something hit the drive shaft, heavy bouncing rock, whatever (maybe even took a trip once over the thing as it road around the tunnel) and it caused a it to chip. If that happened it would only be a matter of time before it got worse and failed.

Also considering Nissan replaced it without making you go through getting an act of congress makes me think you are not the only one.

Chris

 

I agree. They covered the repair so the mention of heat and your mods was probably just a faint attempt to see if went for it. If they really thought your mods caused the issue they would not have covered a thing.

 

yeah those run of the mill nissan techs sure know their stuff don't they?

 

This is my theory as well...maybe the mechanic banged it when installing your exhaust? Anyway, doubt it was heat failure. Here are some quotes I found in regards to carbon fiber and heat:
...as well as from the service manual, which is emphatic about protecting the driveshaft when working around it and to replace it if there is any nick or scratch.

 

This post really intrigued me for some reason so I took the extra step and contacted ACPT, a specialty aftermarket manufacturer of CF driveshafts. They didn't answer my exact question but I think you my find it helpful none the less:

Q: Is a Carbon Fiber driveshaft more or less prone to heat failure from close proximity to exhuast components than conventional steel or aluminum?

A: Thank you for your interest and inquiry in ACPT's world class performance products. All our drive shafts are wound with a High Temperature Resin system, capable of 325F temperature. In all our testing we've never experienced any drive shaft failures due to heat from exhaust piping.

If you have any further questions, feel free to contact me.

Kindest Regards,

Peter Manekas
Product Engineer
ACPT, Inc.
800-799-7893
714-895-7766 - fax
www.acpt.com

 

thanks.. so i know it wasnt the exhaust then and i dont have to change it out. I knew it didnt make much sense, cause if the exhaust was putting out THAT much heat, how were the wire ties that were holding my zero gauge in place not melted?