willycavs10

Hey everyone,

i recently purchased a 48" low-profile LED lightbar for my truck as i am a volunteer firefighter. i got it for 350 on craigslist when their worth thousands of dollars new!

so heres my issue

i put it on (perminant mount) and its so secured to the roof that it makes little dimples in the reflection near the mounts so i know its SUPER secured. i was taking it for a test drive and i got over 50 mph and i heard this low pitched rumbling and i touched the roof of my truck and felt it vibrating at the same pitch as the sound

my thoughts:

i thought that maybe the lightbar is tilted slightly backwards (like a reverse spoiler) and is catching air under it and wanting to lift off like a wing and will only vibrate when winds are over 50mph

could my bug-deflector on the front of the hood mess up my aerodynamics on the roof?

could i make some sort of a wind deflector or a spoiler to mount on the front and bottom of the lightbar to direct wind over it? like the front slope of a roof rack or a spoiler?

any ideas on aerodynamics?

any ideas at all?

thanks everyone

willycavs10

its mounting feet are similar to these pictures but it has metal straps coming from the sides that bolt on to hug it to the roof and is drilled through the door jam

http://pic.globalimporter.net/upload...1420686871.jpg

jhelrey

I know on some of our old squads, it would hum. The brackets that seemed to be quieter were the ones that hooked on the door, then were self tapped into the door frame.

willycavs10

thats what i have! i think i might fabricate an air-dam for the front

willycavs10

PROBLEM SOLVED!

I shimmed up the back of the light bar a little and it fits perfectly and no more noises! plus when my dad saw the lights flashing for the first time it was all he could do to hide a toothy grin thinking "damn, now that does look good" !! thanks fellas!

Mb Offroading

What does the fabricated mount look like??