Lots of noise on start up?

[ctupton]

Hey guys need help on something... My Hummer makes lots of noise on start up. Sounds like a jet taking off and I was told this is a normal hummer sound that they make when they are warming up, and the noise will go a way after a few minutes of driving... well I can drive to work and it will still be on, whatever it is zaps the power as well. To me sounds like a cooling fan and usually if I floor it or put in neutral and floor it will engage and silence. But none the less it is annoying that it can go 15 miles in heavy traffic and not turn off. When I asked the dealership when I went back to pick up hats.. they said it was normal and that it is part of the 4x4 system but shouldn't make the noise more than a couple hundred yards.

Help!

Also I think it is kicking the crap out of my gas mileage as well, 156 miles on half a tank and that is mostly highway, not sure how exact the half tank is mark is vs how much gas is really in there.

[H3slate]

Your gas mileage is about average. Of course when you are just guesstimating it is hard to tell. I usually get about 280 miles off of 19 gallons. I would look into a leak in your exhaust, and force the issue at the dealership. Mine is noisy when I turn it over to start, but quickly quiets down.

[wpage]

Mine is usually noisy when cold but quiets down after a 1/4 mile approx. Could be you have low fluid condition.

[Planohummer]

1)sure you're not in 4hi lock?
2)fan clutch?

[ctupton]

I'm not in 4Hi, but I was wondering if it was the fan clutch.

[Texas Red]

I have noticed the abnormal roar too. But like your dealer said it only lasts a couple of hundred yards. Thing is, it doesn't do it on every start up -- only occasionaly.

[wannabeH3]

im lucky if i get 200 with my 35's on 240 with the 33s

[wpage]

Originally Posted by wannabeH3

im lucky if i get 200 with my 35's on 240 with the 33s

You should be doing much better than that! Around 300 with 35's and 350 with33's

Get it checked.

[3Hummer]

your gas mileage is about right one, mine is stock, and i get about 150-170 miles out of the first half of the tank, and overall i get about 280 miles out of each tank, i fill about 19 gallons each time so do the math, but its not hurting your gas mileage. Mine is also a bit louder when i first start it up in the morning, but goes away by the time i get down the street. Take it to the dealer and tell them to look at it, not just assume, if your car is under warranty, you wont pay a dime.

[ctupton]

Cool, well I'll try to make a service appointment soon and get it in... glad my mileage looks right....

[RubHer Yellow Ducky]

My loudest noise is the brake grinding... guess i'm lucky...

using the gauge i feel good when i get 200 miles on the 1st half and another 100 miles on the second...don't understand why the gas gauges are not more accurate. 15 MPG is a good overall average for me. Highway only i get 19 to 20 mpg...

wherever possible i put on the cruise control and try and keep my highway speed under 65 mph

BTW...i use the A/C over 99% of the time

[fourfourto]

There was a thread some time ago about the tentioner pully making noise at start up ? I never had that problem .
I have been living with the brake noise(normal says hummer rep ) since 2005 GRRrrr.( a little brake lube at rotation is a temporary fix.)

My wife drives kinda hard 15 1/2 around town 14 1/2 in the winter using auto start. 75MPH on Hwy im getting about 18 on a trip a little more or less depending on speed.
Pulling a 4,000 camper about 12 1/2 to 13 MPG at 60/65 depending on hills.if I run 65 to 70 I wont get more then 12.

[Dani]

I too have this noise however I've noticed that it's usually only when it's cold outside. If I let it warm up before driving it usually goes right away.

[HummerJim]

I had the same noise, especially on cold start ups and solved it by spraying WD40 in the shaft of the engine belt tensioner pulley. The noise would come back after about 10 days and I would spray it again. Hummer replaced the tenison pulley under warranty and it never made any noises again. There's a thread about this the first winter the H3 came out, I think by F5stop, and it boiled down to a handful of H3s had noises from the tensioner pulley.

[ctupton]

I took it in, and it of course didn't repeat said noise.. took it on a road trip this weekend, and while in Lubbock, darn thing made noise the whole time we were driving around the town... and stayed on for first 35 miles after leaving town to head back home.

[blindzebra]

if I'm not mistaken it's a extra clutch that kicks into your cooling fan on start up and when your engine is running hot. Yes?

[ctupton]

That is what I think it is... but never an issue once it engages.. it is quiet as can be. just sometimes it takes 30-50 miles to engage, other times about a mile.