Short Version:
What would make a noise like a loose fan belt intermittently chirping from the bellhousing area?

Long Version:
I bought my truck new off the lot in 04.
With 60 miles on the clock I arrived at home and did my first mod. I replaced the stock exhaust with the Bassani catback that I took off my 99L.

While I was under the truck looking at things I noticed that one of the bolts holding on the flywheel inspection cover was not screwed in all the way. (threads showing and finger loose). I thought I was so smart because I found this little oversight and hoped there were no others and was glad I have a warranty....

Well, it wasn't long before I noticed this chirping sound that I thought was coming from the new belt wearing in. It didn't get worse and I only noticed it at idle at stop lights and that wasn't all the time. Sometimes it would do it and other times not. Sometimes my whole drive would be without noticing it.

I decided not to go whining back to the dealer at such an early date and see if it got worse or just what. As the months and miles added up I had no other problems or concerns with the truck.

At one point I crawled under the truck to look for the sound and noticed it was louder. Then I remembered that loose bolt and sure enough with the inspection cover off it was much louder and definitely coming from inside the bellhousing area.

With only 13K miles now on it and cold weather here. I notice that it makes the noise even when I'm driving around, not just at idle. I switched to all season radial tires for the winter and they are narrow and quieter than the stock tires. Now I hear the noise more often than before. I don't feel like it is getting worse and I'm not seeing any fluid leaking anywear or metal filing's but it bugs me more and more just knowing it's there.

I was kind of thinking about going with a performance torque converter but I would be super disappointed if the sound stayed.

Looking back I'm sure that someone before me investigated that noise but didn't do the fix???? I really don't want the dealer fiddling with it and I don't know if something like this would be covered under warranty. Now I'm thinking I should have at least taken it in for documentation.

I don't know what to do but I want it to go away. It's embarrasing to be driving such a fine truck that has a bird chirping under the hood. It's only supposed to whine while the tires burn.

Anybody have any ideas what it could be or what to look for along with a fix?
Thanks
EZGZ

 

Get a louder exhaust















G,
If your positive it's coming from their then you may want to have it checked out. I know you've towed with it many times so my thought is maybe a cracked Flywheel, that will make quite a strange noise, (been there done that 5 or 6 times on my old Big Block Chevelle's)

Good to see you up and around my good Friend
Merry Xmas :santa:
Health Wealth and Happiness to You and Your Family

 

Just a thought, but check your torque converter bolts to make sure they are all tight...if they are loose, it can make a noise like you're describing.

 

I think I have the same noise, just started last weekend.

 

Mine had a similar noise a few weeks back. Turned out one of the internal parts in my tc broke.

 

Thanks for the replies.
I have towed with it that is true, but it has made that noise since I got it. with 50 miles on the clock.

I was so excited when I got it and being one of the few things that I bought brand new I figured in the beginning it was just the new belt and bearings and pulley's getting to know one another.

Like I said, it comes and goes with no particular pattern or weather condition. I just didn't want the dealer people messing around with it because as I said, I found that bolt on the inspection cover backed off like someone ether forgot it or was investigating the noise. Ether way it never got fixed???

Any other thoughts or comments on my noise bellhousing are welcome. I will check the TC bolts when I can.

 

I found one lose tc nut, but the sound didn't go away. I took off the oil fill cap and the sound went away. I dought that had anything to do with it. I'll have to wait till it comes back and look some more.
It's miller time! :santa:

 

Same thing you guys are saying. Sounds like its either in the oil pan or when I took the dust plug out it got worse. Mine does it only when its warmed up and loudest at idle. Any ideas other than tc, mine is an FX4.

Texasflash

02 Screw
Air force 1
Superchip
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Flowmaster series 70

 

It's has to do with air getting sucked past the rear main seal. Put a breather cap on it.

 

+1 on the above post

 

Well, I had a similiar noise a couple of months ago coming from the bell housing area at idle when warmed up and it actually turned out to be the pcv system believe it or not.

Drive the truck till it warms up and park it and let it idle. When you hear the noise unscrew your oil filler cap and relieve the crankcase pressure and see if the noise ceases. If so, it's your pcv system...either a pcv valve (mine has 2 with the L/I kit) or, in my case the pcv line going from the T down to the lower intake was closing off at the elbow. It took me alot of time and searching of ALL the forums to finally find my problem. Good luck!

 

If your rear main seal is sucking air bad enough that you can hear it over everything else then you have a serious problem (which would include a major oil leak).

 

not necessarily, if its only sucking in through the seal it will keep most oil at bay, now if its both pulling air in under vacuum and pushing air out under boost then yes you will have an oil leak. I have a S/C SBC motor that does the same thing at idle when the vacuum level is extremely high and it does not leak oil through the main seals and that an 800+hp Procharged LT-1 motor.

My L had an annoying hiss/squeal when I put on the 4lber in the bell housing area untill I installed a breather, no oil leaks as of yet and that was 20,000 ago and I have since put on a ported blower and a 6lb lower.

since the PCV on the L motor is on the intake of the S/C when at an idle condtion or non-boost condition the vacuum level is in excess of 20" HG when the TB blade is closed,and can pull air through seals quite easily as most seals are not designed to prevent air from being ingested by the motor only keep the oil in and oil is denser that air by a fair amount.

many L's have this problem and it is easily fixed by adding a breather or eliminating the PCV completely

 

You're confusing intake vacuum with the crankcase. They aren't the same. The PCV valve controls or meters the amount of vacuum pulled on the crankcase.

 

if you have 20"Hg on the PCV then the you have 20"Hg pulled on the Crankcase UNLESS it is open to the air.

the PCV is a one way checkvalve not meter

No they are not the same but they are interelated and codependant.

all that matters is that the problem has been solved, it doesn't matter how or why.

just my measly $.02