[eclipsor]

I have a 2008 335xi with AR 3" catless downpipes and a catless AE exhaust. Not only is the exhaust not fitting perfectly (one of the hangers in the rear is not lined up properly and touching the hanger on the car), but the downpipes are rattling against the subframe. This is a very noticeable rattle and I'm just wondering how to fix it short of heating something up and bending some metal.

Any ideas?

Thanks.

[vasillalov]

You sure you received parts for XI? Cause I have AR catless downpipes for AE perf catless exhaust on my 335i and everything fits like a glove! The shop who installed them for me said that they have never seen a downpipe + exhaust combo fit so well. They did not even have to adjust anything. It all bolted right up and everything was centered. No rattling here...

[eclipsor]

Originally Posted by vasillalov

You sure you received parts for XI? Cause I have AR catless downpipes for AE perf catless exhaust on my 335i and everything fits like a glove! The shop who installed them for me said that they have never seen a downpipe + exhaust combo fit so well. They did not even have to adjust anything. It all bolted right up and everything was centered. No rattling here...

I told them that I had an xi when I purchased the parts. How big of a fitment difference is there between the i and and the xi? I was assuming that if it was for the i, it wouldn't have fit at all. Is it so close that you can make either parts work on either model if you "force" it?

[ar design]

Sounds like something was not installed correctly. Who put everything on?

[Kevin@AKMotorwerk]

Originally Posted by eclipsor

I told them that I had an xi when I purchased the parts. How big of a fitment difference is there between the i and and the xi? I was assuming that if it was for the i, it wouldn't have fit at all. Is it so close that you can make either parts work on either model if you "force" it?

xi dps appear to be longer, and have less aggressive bends in them, i have never installed a set of AR design on an xi and have them that close to the subframe or anything

did you check it yourself? is the hanger bracket thats towards the rear o2 sensors in the way and hitting the dps?

[eclipsor]

Originally Posted by ar design

Sounds like something was not installed correctly. Who put everything on?

A local shop... they're pretty good at what they do.

The clearance is VERY tight. The downpipes aren't touching when the engine is turned off, and probably one-third of the time you can't hear the rattle in the car. The other two thirds of the time, however, the rattle is present. Seems to happen more at certain RPMs and after the car has reached operating temp.

Originally Posted by Kevin@AKMotorwerk

xi dps appear to be longer, and have less aggressive bends in them, i have never installed a set of AR design on an xi and have them that close to the subframe or anything

did you check it yourself? is the hanger bracket thats towards the rear o2 sensors in the way and hitting the dps?

I'm going to check it all again tomorrow and take pics so I can post them.

[vasillalov]

Wastegate rattle?

[eclipsor]

Originally Posted by vasillalov

Wastegate rattle?

No no, definitely not. I know what an exhaust rattle sounds like. And feels like. You can feel this through the entire car.

[forza1976]

Could be rattling against the heat shield that sits on top of the subframe, just below the dp's. I took that off when my AR catless dp's were on, it's very tight fit in there.

[eclipsor]

Originally Posted by forza1976

Could be rattling against the heat shield that sits on top of the subframe, just below the dp's. I took that off when my AR catless dp's were on, it's very tight fit in there.

To be honest, you could be right. I'm not 100% positive that it IS hitting the subframe. I just know it's hitting somewhere. Somewhere solid, too, because it's definitely a solid rattle.

[Kevin@AKMotorwerk]

Originally Posted by eclipsor

To be honest, you could be right. I'm not 100% positive that it IS hitting the subframe. I just know it's hitting somewhere. Somewhere solid, too, because it's definitely a solid rattle.

my bets are on the factory dp hanger by the rear o2 sensors, or the "w" clamp was never put back on and its hitting the upper half of the clamp

[eclipsor]

Originally Posted by Kevin@AKMotorwerk

my bets are on the factory dp hanger by the rear o2 sensors, or the "w" clamp was never put back on and its hitting the upper half of the clamp

Could very well be the hanger. I don't think it's the W clamp, though, as I believe that was reattached with longer bolts.

[SfValley335i]

my AR DP's would rattle against the heat shield on the right...

[ultimateendz]

id place my bets on the heat shield....first shop that installed mine put them ON the heat shield and they rattled till it burned a hole straight though it....second shop readjusted it so there was space and viola!!!...all fixed

[Mike@N54Tuning.com]

I would go back and get them adjusted. The XI pipes are a tight fit but there should be no rattling. I have probably sold 10-20 XI sets to customers over the last year and one customer did have a rattle, but it came down to the shop not installing it correctly. After the trip back to the shop everything was 100% rattle free.

Mike

[ultimateendz]

Originally Posted by Mike@N54Tuning.com

I would go back and get them adjusted. The XI pipes are a tight fit but there should be no rattling. I have probably sold 10-20 XI sets to customers over the last year and one customer did have a rattle, but it came down to the shop not installing it correctly. After the trip back to the shop everything was 100% rattle free.

Mike

^THIS

[Penn999]

Originally Posted by ultimateendz

^THIS

I have the same rattle, just thought it was normal. GOD DAMMMMIT, another trip to the shop. I dont have time for this stuff...

[ultimateendz]

Originally Posted by Penn999

I have the same rattle, just thought it was normal. GOD DAMMMMIT, another trip to the shop. I dont have time for this stuff...

yup...its a pretty annoying rattle...especially low rpm driving....when your on it you dont hear it but u certainly feel it...FYI OP...i have AR dps and AE exhaust as well...but im an e93

[Penn999]

So do I take off the heat shield or go back and try to get it repositioned?

EDIT: Am I hurting anything in the mean time?

[ultimateendz]

Originally Posted by Penn999

So do I take off the heat shield or go back and try to get it repositioned?

id leave it on...it can be repositioned....unfortunately i was new to the aftermarket scene and the shop i had do it the first time did it on jack stands and not a lift....i flamed myself for that mistake

[ultimateendz]

Originally Posted by Penn999

So do I take off the heat shield or go back and try to get it repositioned?

EDIT: Am I hurting anything in the mean time?

not really aside from burning a hole in the shield...if it was ON the shield like it was on mine and not just rattling from the engine movement it may start eating away at your subframe....fortunately mine was caught before it did any real damage

[Penn999]

Originally Posted by ultimateendz

not really aside from burning a hole in the shield...if it was ON the shield like it was on mine and not just rattling from the engine movement it may start eating away at your subframe....fortunately mine was caught before it did any real damage

jesus, how long did you take b4 you fixed it? BTW I just took a joy ride to see what they sound like on a back road. Its only really loud between 2-3k rpm. Does this sound like its rattling or just raspy bc of the lack of cats? Thanks for the help.