lateott

What did you use, what did you do?

mtk00

There is TSB for rattling exhaust which is pretty useless. What you need to do is stiffen (or replace) the flex pipes shown circled in B. I used simple stainless steel hose clamps 4” diameter which are about 1/2” wide. Again this is the “cheap” solution to the resonance/vibrating that occurs just under 1000rpm (park, neutral, slowing at stop light etc), not any high rpm vibration which is not what i experienced.

Raise car (Jack stands or air suspension in off-road mode if you have it) and remove plastic skid plate under motor. I put about 5 clamps on each side - spaced evenly but don’t worry too much about them being straight because you actually want to restrict some motion of the accordion-like flex pipe, so if they are angled a bit they will bite on multiple ridges of the accordion which is what you want. Make sure they are tight. That’s it. You can trim the excess clamp if you like but they don’t interfere with anything - and the pipes still flex a bit allowing the motion of the downstream rubber bushings.

Goes without saying to first have a friend modulate the throttle while you are under there before beginning so you can verify the issue - I was shocked how much the pipes vibrate all the way to the back of the car.

lateott

Thanks for the details, I was wondering what clamp size to get and you saved me from measuring. I will give it a try.

Did you confirm noise from both right and left flex pipes on yours? If so, that sure says something about the design flaw in these things. I know when they replaced my downpipes and everything under the first TSB over a year ago they did both sides. No idea if they actually needed to do both sides, but they did and there was no rattle for over a year.

mtk00

Yes it is definitely both sides vibrating together (the pipes are tied together once you go back far enough). Do both flex pipes and please report back here. I could see how resonance issues can go unnoticed in a design, but still disappointing. I feel like another or better support bushing near the flex pipes would be a better design.

Btw - what part are you calling the down pipe? There is the manifold off the block, the cat section which is pretty short, then the long pipe beginning with the flex pipe which contains the front muffler. What did they replace?

zhouge

Thanks for sharing your fix and I think it's the right direction and resonance at low rpm is the root cause. Just want to point out, the flex pipe and close along the downstream is pretty hot exhaust temperature. The regular stainless steel clamp won't last long. We may have find some high temp resistance steel to stiffen it up locally.

cshocker

I found this "fix" online the other day and tried it on the hangers. Working great and got rid of shaking exhaust and noise.

frb1@

I fix the noise with making a weld betwen two downpipes and add some extra toungue , but its not good because tension will stay there because no vibrating and you will have vibrate in the stering wheel

frb1@

i make this and a weldind between two downpipes , no more rattle sound , but have more vibration in the stering wheel , its normal because thay should move in some point ,