What is This sound from my engine?

[Michigan]

"Looks like they are all there". This does not sound very convincing, but you are in charge of collecting the info.

I would rule out any sort of exhaust leaks first, where broken manifold bolts, cracked manifolds, leaking pipes at manifold.

It could be piston slap or something else. Very hard to tell over the Internet without hearing anything.

Lmao I don't think I convinced myself to tell you the truth. I don't know if this is accurate but I think there is a metal sheet like thing that's attached to the manifold with 4 screws on each side. I checked to see if those were all there and they were then I told myself I don't think that's what I should be looking for so I looked for the bigger bolts that hold the manifold and indidnt see any missing from what I can tell.

I'll have my coworker take a look since he knows cars and will know exactly what and where to look

 

[jfoj]

You are correct, there is s sheet metal shield on many of these trucks, but you can still see the exhaust manifold bolts easily if you just LOOK!

How does this work for you?

 

[Michigan]

You are correct, there is s sheet metal shield on many of these trucks, but you can still see the exhaust manifold bolts easily if you just LOOK!

How does this work for you?

You my friend have saved me a lot of hard ache trying to figure out this problem. Thanks for pressing me to look at the exhaust bolts.

I went out to the truck first thing this morning and seen that the bolt near the firewall on the passenger side is missing. I still wasn't convinced for sure. Lol. Or maybe more so I wasn't convinced this is the cause of the noise because with my luck I figured my engine can blow at any time

So on my way to work I stopped at a shop and had them take a look and it is indeed missing. Only the one bolt near the firewall so you called it on that one. All the bolts on the driver side are still intact.

The guy said its nothing serious and does not need to be replaced. He said its just more of an annoying issue and to leave it as is. He said to wait until it gets louder and then think about changing.

He said it will cost 450.00 for each side and if any of the other bolts break while doing it, that would cost $50.00 a bolt.

So if I were to do it id only do the passenger side at 450.00 and additional 50.00 per bolt if they break.

Does that sound like a good quote if I were to consider it? Even though I will most likely wait for now. So I believe my engine is healthy now. Big wait lifted off.

Thanks again and to everyone else also

 

[jfoj]

Not sure if you are DIY kind of person, not sure based on your missing the exhaust manifold bolts on the first glance.

What you can do is what I did, I installed clamps rather than trying to remove the broken bolts. I had both rear bolts break on my truck.

The clamps are cheap, as I recall, one is much tricker to install than the other, I do not recall what side was the biggest problem.

You might be able to find a shop to install the bracket for about 1-1.5 hours at tops?? It is not a good idea to let these stay broken, it just will cause the others to fail quicker.

Not sure if it is a good idea to try and remove the non broken bolts??? Might be best to leave these alone. I would want to speak with someone that has a lot of experience removing the bolts. Do the others usually break or can they be removed one at a time without worry of them breaking.

See these clamps, there are 2 version, one for each side of the head.

I have not tried the Amazon/Dorman ones, they are cheaper than the ones I purchased which are listed below the Amazon links.

https://www.amazon.com/DORMAN-917-107-Exhaust-Manifold-Clamp/dp/B00GHT9L4O

https://www.amazon.com/gp/product/B...rd_wg=wIs8s&psc=1&refRID=JPXXF4CZ7TFQ80CMS1GR

These are what I used - http://kralautoparts.com/

The next thing you need to worry about is the rusty brake lines!!! A SERIOUS safety hazard!!!!!

The replacement lines are about $75 on Amazon, they take a few hours to replaced, but it far wiser to replace the brake lines on YOUR schedule then when they blow out when trying to stop in a tight situation.

ALL of the late 1980's to mid to late 2000's models have this problem. TRUST me, if your truck falls in this window where the brake lines were problems and you live ANYWHERE other than say Arizona or New Mexico where there is no rain or humidity, the brake lines need to be replaced!! Usually between year 9-11 on most of these vehicles.

 

[Michigan]

Not sure if you are DIY kind of person, not sure based on your missing the exhaust manifold bolts on the first glance.

What you can do is what I did, I installed clamps rather than trying to remove the broken bolts. I had both rear bolts break on my truck.

The clamps are cheap, as I recall, one is much tricker to install than the other, I do not recall what side was the biggest problem.

You might be able to find a shop to install the bracket for about 1-1.5 hours at tops?? It is not a good idea to let these stay broken, it just will cause the others to fail quicker.

Not sure if it is a good idea to try and remove the non broken bolts??? Might be best to leave these alone. I would want to speak with someone that has a lot of experience removing the bolts. Do the others usually break or can they be removed one at a time without worry of them breaking.

See these clamps, there are 2 version, one for each side of the head.

I have not tried the Amazon/Dorman ones, they are cheaper than the ones I purchased which are listed below the Amazon links.

https://www.amazon.com/DORMAN-917-107-Exhaust-Manifold-Clamp/dp/B00GHT9L4O

https://www.amazon.com/gp/product/B...rd_wg=wIs8s&psc=1&refRID=JPXXF4CZ7TFQ80CMS1GR

These are what I used - http://kralautoparts.com/

The next thing you need to worry about is the rusty brake lines!!! A SERIOUS safety hazard!!!!!

The replacement lines are about $75 on Amazon, they take a few hours to replaced, but it far wiser to replace the brake lines on YOUR schedule then when they blow out when trying to stop in a tight situation.

ALL of the late 1980's to mid to late 2000's models have this problem. TRUST me, if your truck falls in this window where the brake lines were problems and you live ANYWHERE other than say Arizona or New Mexico where there is no rain or humidity, the brake lines need to be replaced!! Usually between year 9-11 on most of these vehicles.

I'm not a diy guy by any means so I would have to find a shop.

I seen a video of someone installing one of those clamps.

If I go the clamp route which in thinking I will. Would it get rid of this noise?

I don't know if there is a gasket for the manifold but I'm assuming that there is and that's why they want to remove all the bolts to replace the gasket? He said he can tell it's leaking exhaust gases because around the missing bolt its black

I will have to look into the brake lines as this is a Michigan truck, Indiana before here so we get rust from the salted roads. I appreciate that also

 

[jfoj]

If I go the clamp route which in thinking I will. Would it get rid of this noise?

Yes, if the noise is an exhaust leak.

I don't know if there is a gasket for the manifold but I'm assuming that there is and that's why they want to remove all the bolts to replace the gasket? He said he can tell it's leaking exhaust gases because around the missing bolt its black

If there is black around the cylinder head, the exhaust IS leaking. No gaskets, just install the clamp (2-3 bolts) and tighten the one bolt down to push the manifold against the cylinder head. I installed my clamps about a year ago and have had no noise or problems.

I will have to look into the brake lines as this is a Michigan truck, Indiana before here so we get rust from the salted roads. I appreciate that also

Michigan and Indiana, you WILL need the brake lines replaced. Trust me. You can get quality lines on Amazon on your doorstep for around $75. You need to check your brake options to see if you have the option that requires the 2 lines feeding the rear brakes. Not a simple job to have done, BUT, you are much better off planning the brake line replacement BEFORE one breaks or splits when you NEED to stop. Then you have a tow on top of the repair, you cannot shop the repair, if you do not buy the parts they are marked up, you are without a vehicle, and on and on and on!!

 

[jfoj]

Just to update a few things.

1. I am in process of replacing the brake lines on my 2005 Yukon Denali just as a Preventive process. When I went to replace the lines that ran under the drivers floor area, one of the lines was already seeping brake fluid!! I just had a deep down guy feeling after some research and talking to people that by year 10 these lines are in BAD shape. I guess depending on where you live and how the vehicle is used that it is important to inspect the lines CAREFULLY by year 7 and replace the lines by year 10. This is a CRITICAL safety issue.

The lines from the ABS unit that run under the driver compartment seem to be the first ones to leak.

Word to the WISE, replace the brake lines, even if it is just the very bad ones before they blow out. You can get the lines for less than a cost of a towing bill and you can replace the lines on YOUR terms and YOUR schedule, not the vehicles terms and schedule.

Note on the exhaust manifold bolts, they are a PITA do deal with. Best to remove the manifold(s) and remove the bolts from the wheel well with the inner fender liner removed. The rear most bolts may be impossible to remove and this is where the clamps come in handy. If the bolt head just broke off, you can hopefully use a stud removal socket, but you may need to thread a nut on and weld it to the bolt. The OE bolts are case hardened and even a stud removal tool may have a hard time grabbing the shank of the bolt. There are exhaust manifold gaskets, they are a 3 layer stainless steel metal gasket that is actually 3 separate pieces. I think they can be reused without a problem. I would be a bit worried about what the auto parts store may have for replacements. Might go with dealer gaskets if the parts store look sketchy.

 

[Michigan]

I will definitely have the brake lines checked. Just a visual inspection should be ok I'm assuming

As far as the exhaust manifold bolt being broken goes. I've been asking myself if this is actually the source of all this noise. I'm really hoping it is and not something else with the engine. One guy told me that a broken bolt should not cause all that noise but just read some symptoms of a bad exhaust manifold gasket and I have the symptoms of it with the tapping sound on idle and acceleration.

I've been doing some thinking and I don't want to go the clamp route, I think I may or may not need the gasket to be replaced but will go ahead and do it either way.

While I was talking to the guy at the shop last week I asked him if I could or should replace the manifold with a header and not sure if he knew what he was talking about but his answer was that I shouldn't do that because these engines are tuned for certain something and that adding headers can actually cause the truck to bogg out during acceleration and that the engine would lose power unless I added a full exhaust and a tune.

Anyone think it is a bad idea or good idea to replace the manifolds with headers with the rest of the truck being all stock? If so, is there a certain one or part number you can give me. Thanks

Also I may be adding a flowmaster muffler after I get this problem situated but it will most likely be only the muffler and not a cat back

 

[jfoj]

First, DO NOT bother with a brake line inspection, plan on a brake line REPLACEMENT. Unless the brake lines have been replaced in the past few years by a prior owner, they NEED to be REPLACED. It is not IF the line will fail, but WHEN.

I have a very close friend that has replaced 4 sets of brake lines on 2004 in the past year, he showed me how bad the crusty rust were on lines he still had not carted off to the recycler. My lines were not even close to crusty, but just had some surface rust, but when he looked at the normal location they tend to leak, my lines were wet, so I caught the problem just in time. The only reason I decided to replace the lines is because when he told me he had 4 2004's that he had recently replaced lines on, I knew I had a 2005 and my time was almost up!!! My guy feeling was RIGHT!

As for the broken bolts, not sure how many are broken and what side. The rear bolts probably cannot be replaced on the car easily. Probably will require cylinder head removal. I would use the clamp brackets in a heartbeat, not sure why anyone would not use them if they can save time and money, they work very well.

As for headers, do not do this, the converters are close to the manifold and you will likely loose the converters.

For someone who does not want to replace the brake lines, not sure why you would worry about headers and a muffler. The truck NEEDS to stop when you NEED it to stop!!

Priorities, SAFETY first.

 

[jfoj]

Here is what I had. My brake lines were not nearly as crusty as some that I have seen. And for the record, I had not lost braking and had no idea this was leaking!