loud BUZZ from under the hood

[wide body]

i don't get the noise all the time but if i'm driving into a strong headwind or when the hiway speeds are above 65 i get a VERY loud buzz from what sounds like the firewall area. it sounds similar to noise you get when let the air out of a balloon when you are pulling the neck tight. don't know if that makes any sense or not.

when i open the hood, there is a thick, what looks like a heat shield, that is attached to the firewall that runs the width of the truck. in the middle of firewall, there is a fair amount of "sag" in the shield. i'm assuming this is what's making the VERY ANNOYING NOISE! what can i use to re-attach this insulation/heat shield? it doesn't appear there are any screws or clips there to fasten it back down?

any ideas?

[HSV250SD]

Stick on weld pins

[deamsphelps]

check your coolant level. I know it sounds crazy but I had the same thing.

[wide body]

Originally Posted by deamsphelps

check your coolant level. I know it sounds crazy but I had the same thing.

what? are you serious or just one of those things to see if i'll do it?

i know when i was in the marine corps we used to send the new guys down to the squadrens and have them ask for 100 yards of flight line......there is no such thing, the entire area is called the flight line

if you're not pulling my leg, what in the world is involved with the coolant that could cause that?

[deamsphelps]

Serious. I am not in your truck so I don't hear the sound you are hearing obviously. I had a sound that sounded like riding over a rumble strip or like a fan clutch engaging. I came on here and did some research and found something about it. My coolant was a little low and I added and sound went away. Take it for what it's worth instead of arguing with me.

[wide body]

first off, thanks for the input.

second, i wasn't arguing with you. i was making sure you weren't putting me on. you have to admit the idea doesn't make a lot of sense, but if it works...it works. i'll certainly check it out. i guess i should have put some smiley faces or something in there somewhere. lighten up a bit, no offense meant, no arguement made....thanx again for the suggestion.

[deamsphelps]

I don't post on here much so you won't get a smiley face from me. Just let get back to me on the coolant level. Scratch the rumble strip sound. It was more like the sound of a motorcycle where there was none. It scared me because my truck would make mincemeat out of a biker. It was on and off the whole way home from work (about 40 miles). Coolant was below the add level. never heard the sound again. I thought the turbo was going. Good luck.

[dazed01]

Sounds like some loose rubber trim. Chevy has issues with their aveo doing that with a crosswind. Take an air nozzle hooked up to an air compressor and blow air around the areas making the noise to see if you can reproduce it. Their fix is double sided tape under the seal.

[wide body]

dazed....excellent idea!

deamsphelps, mine is generally very hit and miss too with one exception......the ENTIRE way from parowan utah to las vegas

the only way i could get it to stop was to run 64 mph when the speed limit was 80! that trip SUCKED!!!

[rlpzzz]

Is it a buzz or does it sound more like a Kazoo? My truck had made a kazoo type sound, ended up being the windshield seal. Very loud and very annoying I must say.