ok guys,imy wife was telling me the hummer was making a "funny" noise,you know how that goes,well so be it,so i am out driving it this morning,which i never get to do,and i noticed at about 35-40mph i hear a humming coming from under the hood,i let of the throttle,and it goes away,i get back on the throttle,it takes a couple seconds,then there it is again.im baffled,its a stock intake w/ a k&n filter.do you guys have any ideas,i tried a search and nothing popped up.thanx

 

check the 10mm nuts that hold the heat shield on to the exhaust manifold that sometimes comes loose and makes that wierd noise one might have vibrated right off check close......... its nothing serious though, if that is what it is.

 

really,i will check that tomorrow,but she has also been getting bad mpg,like down around 12-13,something cant be right

 

i reread your post and i am thinking you should check your front diff that could be the problem or a wheel bearing

 

[sm=WTFsgign.gif]DOWN TO AROUND 12-13??? Wow...13 mpg is all I ever get and she runs great! Maybe that's the problem....A little too much right foot.

 

I had one once. I guess you could call it a humming sound.
If its at 1800-1900RPMs, this could be the problem.
The trick is to do a powerbrake (use the e-brakeAND regular brake) test to tell if its an engine vibration or a drivetrain vibration. If the engine isnt under load, its pretty steady.
https://www.hummerforums.com/m_21458/tm.htm

 

its nothing like that,i am pretty sure it has to do w/ air coming in the intake,i think i am going to put the stock back on and see if it continues,i bet this thing is just getting too much air,i dunno

 

its not a loud humm,really soft,heck it tookme a little bit just to hear it,it has to start at the filter and go to the throttle body

 

i wonder if it could be the k&n filter,i think i will try the stock one again and see what that does

 

well,i think i figured it out,tha fan shroud wasnt in the groove on the top like it is supposed to be and im thinking the vibration is what was causing it,i guess well seee,she knows every little sound that thing makes,and when it nmakes one she doesnt know,boy do i get an ear full