I have a Flowmaster muffler on my truck, which sounds great - but I have a problem that's been bugging me and was wondering if any of you all had experienced anything similar to it or have any ideas for me.

When the RPMs reach approx 1700, I get a 'vibration' sound (it's obviously exhaust related - the truck is smooth) from the rear right side (muffler side). It sounds like an aluminum or other light metal piece vibrating. Past 1800 RPMs, it is gone. Took it to the dealer and they fixed it under warranety stating 'RE-POSITIONED MUFFLER HEAT SHIELDS' Noise went away - for a couple weeks. Now it's back.

I looked under there myself, and I see the shield, it's obviously not hitting the muffler, and it looks like it could be making the sound I am hearing, but it's nice a tight. Also, the noise only happens when the vehicle is moving, so no luck on listening while the engine is reved up and in PARK.

Anyone have any ideas/suggestions? I'm thinking about pulling the shield off, drive it around the block to see if that is really the problem, and then put it back on again, maybe w/ some rubber washers in place. Good idea? Anyone ever hear any wierd noises after putting on an aftermarket muffler?

Otherwise exhaust is great.

Thanks in advance.

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Silver_Roush
1999 Ford F150 Roush


[This message has been edited by Silver_Roush (edited 11-10-1999).]

 

I have the same type of sound, and haven't been able to locate it. Its driving my crazy!!! I will check the heat sheild.

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99 F-150,XLT, Silver, 2WD, 4.2L, 5spd, RegCab, Shrt WB, Styleside.
Current Mods:Billet grille, Line-X bedliner, 5%window tint all the way around, Alpine CD w/2 MTX Subs & Rockford Fosgate 250w amp. K&N Airfilter. Glasspac w/dual exhaust exits out the back. Blue Ion Headlights.
Future Mods: Superchip, driving lights, & a custom paint job

 

I had a similar problem after installing my Gibson exhaust, only mine was "buzzing" at idle. It sounded like it was coming from the heat shield, but wasn't. There are some corrugated steel panels above the shield near the truck bed. I poked around with a wooden dowel until I found the vibration, and then just put some pressurre on it until it bent a little. No more buzz . Hope this helps, those kinds of noises can drive you nuts.

Steve

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Steve-O, 1997 F150XLT,Two Tone Moonlight Blue & Silver,3.55 LS,Class III Tow Package, 4.6L Auto, STD Cab Styleside, Alpine CD, Soundstream Rubicon, Kicker Solo-Baric Sub, Boston Pro Separates,Tinted Windows, Gibson Exhaust, K&N Filter, Superchipped, Stull Billet Grille, Hella Fog Lamps

 

Do you still have the Vib-Dampner? It's the little 6" long cyl thing bolted to the exhaust pipe between the cat and the muffler.

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2000 F-150 4x2 XLT Supercab Flairside Toreador Red, 4.2 Auto 3.55 LS axle 255/70R16" Factory CD, Keyless entry, sliding rear window. Slim-Top hard tonneau, K&N, Lund Interceptor, Kleen wheels

 

Caddpro & SteveE55, I'll check those panels near the bed, then see if the Vib-Dampner is still on. Whatever I discover I'll post it here. Thanks for the replys. Fordman99, let us know what you discover upon checking the heat shield.

Thanks all!



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Silver_Roush
1999 Ford F150 Roush