View Full Version : Noisy Fan on Cold Start?
PbFut
02-01-2006, 04:14 PM
I seem to have an unusually noisy fan at cold start up. It sounds like the fan clutch is hung up and the fan is blowing a hurricane wind. After just a couple minutes, the noise is gone. NE1 else experience this noise?
blautens
02-01-2006, 04:19 PM
Mine fan is a little noisy on cold start....I think it's quite normal.
Blulytes
02-01-2006, 04:29 PM
Fan is alittle louder on a cold start... standard GM across the board
After the last oil change I had a super loud fan for the first thing in the morning for 2 mornings... then normal, never again.
I just don't ask questions anymore...
PbFut
02-01-2006, 04:33 PM
Thanks for quick reply.
Beats going to a dealer and asking a service writer who just got his drivers license last week.
Envoy Fan
02-01-2006, 04:39 PM
Fan clutches have been an issue since day one in 2001 for the TB's. Supposed to have been fixed in May or June of 2005. This applies to both 4.2L and 5.3L with an updated fan clutch. Hope yours isn't going bad.
Silver_06
02-01-2006, 09:58 PM
Same thing here. Cold mornings the fan is engages on startup.
Jman423
02-01-2006, 10:48 PM
:m2: I would say that the loud fan at cold startup is good, when mine wasn't noisey at startup, I had nothing but problems with my A/C. When they finally replaced the fan clutch and fan, the A/C worked great (and still does), but the fan sounds like a spaceship taking off when I start the truck in the morning :yes: :m2:
ghoster
02-01-2006, 10:55 PM
Mine is noisy at start-up on cold mornings. I asked the dealer about it, knowing there was a TSB about the fan clutch. They looked, but said everything was normal and my fan clutch was fine, though I am nervous about trusting anything they say.:cool:
HOTRODSURFER
02-02-2006, 02:19 PM
my fan is only noisey on really cold mornings and will last about 90 seconds
SUVette06
02-02-2006, 03:07 PM
my fan is only noisey on really cold mornings and will last about 90 seconds
:iagree: mine only lasts about 30-40 seconds
Fishhunter911
02-02-2006, 03:20 PM
:iagree: me too!
LineNoise
02-02-2006, 05:45 PM
Mine gets loud like it's spinning real fast for about 1 second then as the truck idle's down it's fine. But I have a bunch of squeeking coming from the front of the engine, just haven't had time to figure out what it was. It's only when the truck is cold, when it warms up it's quiet.
Dacomputernerd
02-02-2006, 05:50 PM
Mine gets loud like it's spinning real fast for about 1 second then as the truck idle's down it's fine. But I have a bunch of squeeking coming from the front of the engine, just haven't had time to figure out what it was. It's only when the truck is cold, when it warms up it's quiet.
The fan still does that to me also. (spins fast for 1 second then disengages)
I was getting some squealing/squeaking on a cold start if i left without letting the engine warm up. Ever since I put full synthetic oil, the sound is gone, and it starts MUCH smoother :D
LineNoise
02-02-2006, 07:48 PM
The fan still does that to me also. (spins fast for 1 second then disengages)
I was getting some squealing/squeaking on a cold start if i left without letting the engine warm up. Ever since I put full synthetic oil, the sound is gone, and it starts MUCH smoother :D
I am running 5w30 synthetic, didn't really notice much of a difference except my mileage went up.
Dacomputernerd
02-02-2006, 07:51 PM
I am running 5w30 synthetic, didn't really notice much of a difference except my mileage went up.
I have also had a mileage increase aswell. The cold starts i'm talking about are below -8C
jbossert
02-02-2006, 09:25 PM
Same issue here. I've noticed that the clutch disengages after 20-30 seconds if I leave it idle before pulling away. If I pull away right away, it stays engaged for a few minutes.
trailnablaze
09-15-2006, 10:19 AM
My TB has been in the dealership for the 3rd time with the check engine light coming on due to the fan. They say that there is a TSB out for it. I don't understand why they can't seem to get the problem fixed. Has anyone else had an issue with their check engine light popping on due to the wiring harness from the fan getting chaffed. I think they are trying to install some new bracket to bring the wires away from the fan. Also, my truck's fan clutch engages at start up no matter what the weather. Are you all saying that I just need to wait for an extra 30 to 40 seconds before I take off and the noise will go away? That has to be the most annoying thing about my truck!!!
rbarrios
09-15-2006, 01:41 PM
ive heard about those wires getting chaffed once on here....
my 1964 chevy truck, my 1970 monte carlo both have a loud fan when 1st started. Soon goes away. These are thermal clutches with oil in them. At night the oil settles, when you start up, the oil needs to distribute, then it quiets down.
Im sure the Tb clutches are doing the same thing.... something is going in and it releases...
My Tb does this too
Yep! If the fan doesen't sound like an F-18 on startup then it isn't working correctly. If you have an pre 2005 vehicle and it is quiet, then you need the new fan clutch before the old one does go bad.
John Skiba
09-15-2006, 09:34 PM
Yep! If the fan doesen't sound like an F-18 on startup then it isn't working correctly. If you have an pre 2005 vehicle and it is quiet, then you need the new fan clutch before the old one does go bad.
:crazy: If it DOES sound like an F-18 then you have an issue. The only time when my 2002 Envoy fan sounded like that (crap), down on power, etc was when it WAS time to replace the clutch because it went bad. Neither my 02 Envoy NOR my 2006 TBSS sound like an F-18 because of the fans at ANY time.
The 02 did roar like something fierce when the clutch went bad and just stayed on by default. :D
I know my Denali's fan has been roaring since brand new and it will freeze the crap out of you in 115 degree heat while climbing a long mountain grade or in LA traffic jams.
My TB isn't as loud but it starts blowing warm air when idling. The roaring noise should go away once you hit 35 or so when the computer figures there is enough air going through the radiator. Too bad the computer can't figure out that it is 40 degrees or less out side.
John Skiba
09-16-2006, 12:33 AM
I have never had any A/C issues nor cooling issues with either vehicle and neither roars. And yes, the A/C in the 02 is cold enough even on 95+ days to where the autoclimate controls don't have to even command the blower fans midway to keep the interior a nice 70-72*s.
Neither of my vehicles blow warm air when idling prolongs in A/C mode.
If your Denali constantly roars full time, I suggest you take it in under warranty because it definitely doesn't sound 'normal'
trailnablaze
09-25-2006, 10:22 PM
I took my TB in for a TSB on the fan bracket. They replaced to fan, and the harness. The TB does not roar at all, and it runs a lot better.
TonyGXP
09-26-2006, 12:28 AM
I took my TB in for a TSB on the fan bracket. They replaced to fan, and the harness. The TB does not roar at all, and it runs a lot better.
the roar on startup is the fluid that collected in the clutch in the bottom and is thick, until the fan & clutch start spinning and it thins out, the roar goes away.. when you turn the AC on it depends on the Head pressure how much % the fan clutch is engaged, all clutch fans SHOULD roar, on startup form cold and when you rev the gas when either the truck gets to a certain temp or the AC is on and it's called for..Roar is normal Clutch Fan activity... that's why I couldn't wait to get my fans done... so nice w/o that noisy, 50's technology..
my996duc1
09-26-2006, 12:28 AM
Can you give us the details on the "fan bracket" TSB.... I did not know about this one ???
Thanks !
ScarabEpic22
09-26-2006, 01:15 AM
Can you give us the details on the "fan bracket" TSB.... I did not know about this one ???
Thanks !
I think he just means the fan clutch TSB that is basically if its stuck on, time to replace it.
trailnablaze
09-26-2006, 08:21 AM
The fan TSB was explained to me by my tech. as the wires to the harness were getting chaffed, and the fan was stuck on. That is the fan was stuck on all the time. He explained to me that a new bracket was need to bring the fan away from the wiring harness, and free the wires from getting chaffed. Talk about slowing you down!!! I am still getting the Efans, but the truck is running a lot better since I got the TSB addressed.
Can you give us the details on the "fan bracket" TSB.... I did not know about this one ???
Thanks !
I have never had any A/C issues nor cooling issues with either vehicle and neither roars. And yes, the A/C in the 02 is cold enough even on 95+ days to where the autoclimate controls don't have to even command the blower fans midway to keep the interior a nice 70-72*s.
Neither of my vehicles blow warm air when idling prolongs in A/C mode.
If your Denali constantly roars full time, I suggest you take it in under warranty because it definitely doesn't sound 'normal'
It doesn't constantly roar, only on start up or if it is idling in rear hot temperatures. On a normal day, both the TB and Denali's fans on mine shut off once you hit around 35mph. It doesn't matter how cold it is outside, they will still roar at start up.
cmc82178
11-16-2006, 09:53 AM
normal - my 02 LS did it, and my 06 TBSS does it, i work @ GM engine plnat & had one the engineers come out & look at it, i thought i was crazy at first, since it doesn't always do it, but it's apparently quite normal, it's supposed to do that....
vetruck
11-16-2006, 03:38 PM
Normal yes, but acceptable no. Can't wait to get my e-fans on. Everytime I leave the driveway I have flashbacks to when I was an SP on the flightline watching F-16's taxi down the runway :crazy:
eckvoys toy
11-16-2006, 03:46 PM
I Was Getting The Same Thing On A Cold Start. Took It It They Called Me And Said It Was The Fan Clutch Needed Replaced Dont Know How Much Cus Its Still Under Warrenty
the roar on startup is the fluid that collected in the clutch in the bottom and is thick, until the fan & clutch start spinning and it thins out, the roar goes away.. when you turn the AC on it depends on the Head pressure how much % the fan clutch is engaged, all clutch fans SHOULD roar, on startup form cold and when you rev the gas when either the truck gets to a certain temp or the AC is on and it's called for..Roar is normal Clutch Fan activity... that's why I couldn't wait to get my fans done... so nice w/o that noisy, 50's technology..
Mine did the same thing when brand new but 3 years later it is still working fine.