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NEWB question about Quad exhaust

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I took the plates out a few nights ago and drove today. The driver side Quad exhaust is now vibrating on the frame.
Did i tighten the bolt next to the tip too much or something else? I am thinking if i back off the bolt a turn or two it may loosen it up enough. OR do I need to go back to the Hpipe and lower the connecting pipe a little?
Thanks for suggestions


Because racecar.
Arizona, USA
Either the "tip" bolt is too tight, or you may need to undo the bolt that holds the pipe clamp in place and rotate the pipe down a little, check the clearance to the floorboard.
I had the same exact issue. There are two things you need to do, but they are easy and I did it without a lift.

If you look under, there is a band with a bolt between the baffle junction and the tip. There is a little tack weld, but it is only on one side. Loosen all the bolts at the junction and the one holding the tip, and the one at the band. Get the band nice and loose. Then twist the pipes by hand to create more clearance. I had to twist it so the bend in the pipe was lower.

Part two is making sure the junction where the baffle goes is lined up square. I held it with my fingers so the edges all lined up while I tightened it.

Now just button everything up. You can also adjust how far the tips hang under the car while twisting the band area.

Mine, one of the band bolts is straight and the other is tacked on crooked so it is angled up too much. That is why it was banging. It was banging a little even when I picked it up, as installed by the factory (or does the dealer install as part of prep?)

Let me know if I didn't explain it clearly.
Similar problem. Clunk coming from left rear hitting a hard bump.
Loosened left baffle bolts and side clamp, rotated pipe down, retighten all and clunk gone.
Thanks for the tip guys!


Owner of 2012 & 13 Boss 302's
I have buzzing in both doors due to this problem, I've been under there and turned and adjusted, ran different torque on the bolts, used loctite, everything I can imagine! I can get it to go away for a bit but it comes back.... In its current state it will go away if the car is driven hard. Heats something up I guess. I'm at wits end, actually is a major detractor to the enjoyment of driving it! I know its fixable because I can get temporary relief...

Any thoughts or suggestions would be awesome.

(just over 4k of buzzing miles)
DA712 said:
Any thoughts or suggestions would be awesome.

Center the two bolts where the pipe attaches to the main assembly. Then loosen the long bolt on the band and rotate the pipe until you have 3/8 inch clearance to the floor (just enough to squeeze your index finder in there.) If you can not get that with rotating the pipe get it as close as possible then make fine adjustment with the two bolts at the attachment point. You will have plenty of room to work with them if the were centered.

If you still have the noise bring it to the dealer it should be covered under warranty.
Check that the bolts on the bands are tacked somewhat straight. As I mentioned, one of mine was cocked so it required a lot of clearancing by twisting the pipes so the angle is pointed very low. Maybe you didn't twist it enough.

Does it buzz when it is in neutral if you rev it? If so, you can have someone rev it and lay on the ground next to it and verify it is the pipes. If it is, you can use a rag or welding glove to try holding the pipe in various places to figure out where the buzz is. It might be the heat shield or even the dust covers on the brakes, since adjusting the pipes isn't working.

Grant 302

basic and well known psychic
At the baffle with the quad pipe hanging, snug the outboard nut first. Support and align the quad pipe and snug then tighten the inboard nut. Then tighten the outboard nut. Luckily, I paid attention to where the baffle section on mine was aligned when I took it apart. And best I can tell, this is close to the way it was done at the factory.


Owner of 2012 & 13 Boss 302's
Thanks for the suggestions! Being at wits end, I'm anxious to give these suggestions a try.

Will report what happens...

Thanks again!
Im glad i posted as it seems I wasn't the only one experiencing this.

I was able to loosen the bolts , pull down on the pip and re tighten and this fixed it. mine seem to touch the frame about 6 -10 inches after the main junction. i was able to grab the pipe and wiggle it and see exactly the contact point.

on a side note, I am coming from the SVT community (04 Cobra) there is a FAQ and a how to guide someone has put together for the Terminators ( I wish i had timeto put one together or someone would for us newbies. until someone does we will just have fun posting all the easy questions here haha.
Thanks guys, my problem is solved.
I removed the baffles the first day I got mine.

I've noticed a buzzing noise from 2500 rpm sometimes, but all the time over 4k rpm, which comes from an area around the passenger side door. It annoys the crap out of me.

As far as I could tell, neither pipe was touching the frame, by it the clearance is super tight near the floor of the car on both sides.

Is it possible when the engine rotates from torque on the motor mounts that it is twisting enough to cause the pipes to hit the floor? Also, should the outboard nut that holds the side pipe to the rocker panel area be "snug" or tight?

I really don't want to take it to the dealer for this.
Loosen the nuts plus the one on the strap. Tighten the ones at the junction first, make sure it is square and not twisted. Then twist the pipe so the angle is pointing down a bit. Then tighten everything up again. That is exactly how mine was, and how a bunch of the others are. Exhausts vibrate, it needs some clearance.

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