Warning

 

Close

Confirm Action

Are you sure you wish to do this?

Confirm Cancel
BCM
Durkin Tactical Franklin Armory
User Panel

Site Notices
Posted: 1/20/2014 11:16:14 AM EDT
Still a little new to this truck. When I bought it(it's used CPO) I didn't hear any unusual noises. I noticed a tick sound bouncing off a building last night and feared I had the dreaded L76 lifter tick... so I made a stethoscope with a piece of vacuum tube and a piece of a rifle cleaning rod. Works beautifully and listening to the valve covers, valve cover bolts, and exhaust manifolds all I hear is the music of the valve train and all 8 cylinders sound the same. I've still got another month left on the CPO warranty at least.

So I dug more and found the front of the engine is making a little noise that sounds serpentine in nature. Then I noticed the "tick" is noisiest underneath the drivers side of the truck and sounds almost like an exhaust leak.

I made a video of the noise.
Clicky for YouTube

What do you guys think? This LS is a new beast to me, my last Chevy had a TBI 350 in it

So far I love the truck. Has 63k on the clock and drives super nice. Wife hates the gas mileage but I'm happy with the 13.5-14mpg I've managed so far(hand calculated).
Link Posted: 1/20/2014 2:01:09 PM EDT
[#1]
Link Posted: 1/21/2014 12:01:49 PM EDT
[#2]
You called it

Drivers side rear exhaust manifold is broke off or missing. Common issue with these engines. The dealer should fix this as they claimed they back up their CPO warranty. We shall see..
Link Posted: 1/21/2014 12:28:10 PM EDT
[#3]
Link Posted: 1/21/2014 2:27:19 PM EDT
[#4]
The culprit. Couldn't get the phone in close enough to take a pic of the bolt hole.

Link Posted: 1/21/2014 2:31:43 PM EDT
[#5]
Link Posted: 1/21/2014 2:33:45 PM EDT
[#6]
I'm pretty sure it is. The dealer is going to take care of it though.

Apparently replacing exhaust manifold bolts should be routine maintenance on an LS engine
Link Posted: 1/21/2014 2:58:43 PM EDT
[#7]
Link Posted: 1/23/2014 12:04:26 PM EDT
[#8]
Dealer has it. I was there all of a half hour and they said it's going to take a day and sent me on my way with a free rental

They are going to pull the manifold, extract the broken bolt, check the manifold surface and if need be replace it too, and replace all the bolts on the drivers side. Leaves me with the passenger side to deal with since none of the bolts are broken and I don't really want to wait until they break
Link Posted: 1/23/2014 3:25:08 PM EDT
[#9]
Link Posted: 1/24/2014 12:44:10 PM EDT
[#10]
They had to pull the cylinder head to get it out
Link Posted: 1/24/2014 3:09:15 PM EDT
[#11]
Link Posted: 1/25/2014 10:39:40 AM EDT
[#12]
The story I got was the tech took one look at it and decided to pull the head rather than screw with it in the truck. I've read the only way to get the bolts out without pulling the head is to use a welder and weld a washer and nut on.

On the positive side I got a brand new GM head gasket, new GM head bolts, and a bunch of other new parts on the driver side. My exhaust leak is gone! The tech did a good job, the drivers side almost looks like it has a new head on it that's how clean it looks

Still have a noise that might just be me. I can't find the noise in the valve train or engine so I'm pretty sure it's not there. I pulled all the belts since I know I have a bad tensioner and started it and I can pretty much only hear the noise under the truck. I almost wonder if I have an exhaust leak further down the line or a catalytic converter that's going south.

New YouTube Video
Link Posted: 1/27/2014 2:40:23 PM EDT
[#13]
So Friday I got the truck back and everything was great until Saturday it threw a CEL. Code was P1174 Fuel Trim Bank 1, same as it threw on the way to dealer with the exhaust leak. Took it in today and they can't get it to throw the code, but since it's under their warranty they are replacing the o2 sensors and a tech is driving it home tonight and seeing if he can get it to happen on him.

No other issues to report. I thought a clatter/flapping noise was related and it turned out to be the windshield trim rattle that is common on these vehicles, exacerbated by the cold temps.

Hopefully tomorrow when I pick it up I'll be done with the dealer
Link Posted: 1/27/2014 3:00:51 PM EDT
[#14]
Link Posted: 1/28/2014 6:47:52 AM EDT
[#15]
Sounds like the perfect time for some coated Pacesetter LT's.
Link Posted: 1/28/2014 1:52:06 PM EDT
[#16]
Discussion ForumsJump to Quoted PostQuote History
Quoted:
passenger side?
 
View Quote View All Quotes
View All Quotes
Discussion ForumsJump to Quoted PostQuote History
Quoted:
Quoted:
So Friday I got the truck back and everything was great until Saturday it threw a CEL. Code was P1174 Fuel Trim Bank 1, same as it threw on the way to dealer with the exhaust leak. Took it in today and they can't get it to throw the code, but since it's under their warranty they are replacing the o2 sensors and a tech is driving it home tonight and seeing if he can get it to happen on him.

No other issues to report. I thought a clatter/flapping noise was related and it turned out to be the windshield trim rattle that is common on these vehicles, exacerbated by the cold temps.

Hopefully tomorrow when I pick it up I'll be done with the dealer
passenger side?
 


Yup, the trim along the edge of the windshield frame. Apparently it's a common issue.

Got the truck back with new o2 sensors. I am pleased

The only noise present now is my worn out tensioner, which I can't seem to get the parts store guy to give me the right one. I didn't even think to check the dealer parts department and see what the delco part number was and if it looked the same as what's on the truck. My tensioner is only held on with 2 bolts, all the ones the parts store guy could find were 3 bolts. Of course these are the guys that can't think on their own and use the computer only.
Close Join Our Mail List to Stay Up To Date! Win a FREE Membership!

Sign up for the ARFCOM weekly newsletter and be entered to win a free ARFCOM membership. One new winner* is announced every week!

You will receive an email every Friday morning featuring the latest chatter from the hottest topics, breaking news surrounding legislation, as well as exclusive deals only available to ARFCOM email subscribers.


By signing up you agree to our User Agreement. *Must have a registered ARFCOM account to win.
Top Top