jmfranc

I just put a Borla true fit muffler system on and it has a deep throaty sound to it. It's nice but I wanted it to be very quiet. Is there a wrap I could put on it? End pipe that would reduce the noise? Don't have lots of $ at the moment and I would love a simple solution. Thanks!

IanB

You could add a resonator after the cat, and before the muffler. There are no fixes cheaper than that I'm afraid.

87 Deathtrap

They work for guns and grinders, I'll bet they would work for exhaust too.

WHAHAHAJR

Mufflers sometimes will quiet down after a some miles. How long have you had it?

jmfranc

I just installed it on Sunday. I was thinking of adding a heat shield which might deflect some noise. Or spray some heavy black undercarriage spray to dampen the sound a bit or both. Anyone heard of a fiberglass laced exhaust tip that lightens the sound a bit?

BMcEL

Put a quieter muffler on it...problem solved.

Spraying undercoating on the exaust is not only a bad idea, it won't do anything to reduce noise. Neither will a heat shield.

IanB

None of that will help, you either replace the muffler with a quieter one, or add a resonator (essentially another muffler). Give it a few weeks to break in, you might find it calms down a bit.

TOY89

Depending on the mufflers, some get quieter after break-in, while others actually get a bit louder after break in. Borla is a very reputable exhaust system. I would say keep it. Is it really that loud to the point where it bothers you?

jmfranc

I guess what I was wondering was if I add dampening spray to the underside of my 4runner and then add a heat shield over top of the muffler would it help at all. OR does all the noise come from the exhaust tip and there's really nothing I can do. An answer either way would be great so I know where to throw a little bit of money. Thank you for your advice IanB, TOY89, and WHAHAHAJR.

jmfranc

And I would never spray anything ON the muffler. I was just thinking of the area immediately above it.

IanB

The exhaust is loud because the exhaust is loud, not because the underside of the truck doesn't have enough crap sprayed/applied to it. If it's still too loud in a couple of weeks, pick up a resonator and have it welded in after the cat and before the muffler, it will retain the tone/sound of the Borla muffler (which is sex!), while bringing the noise level down overall. It might cost more, but it's the proper way to fix the problem.

Applying products to the truck does not make the exhaust any quieter, you MAY reduce how much noise transmits to the cabin, but to anyone outside your truck, and anytime your windows are open it will be just as loud as before.

jmfranc

What resonator would you recommend? Walker Quiet Flow?

And what size? Do you want it to fit OVER the existing pipes or use same size as the pipes?

bob200587

Your muffler bearings must be bad. You should change them.

IanB

I would normally suggest a magnaflow, but their quality control has gone south the last few years, whatever brand you want should do the job really. You'll have to measure how much room you have to add one, and decide how much quieter you want it to be from there and pick a size. The longer the resonator the quieter your exhaust will be. You would want it the same size as the piping in the exhaust (the inlet/outlet that is).