Engine bay sounds like a box of rocks - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

ss camaro-monte · 11-11-2023, 03:04 PM

Well started the car today and I think this is crazy because I was just asking about possible shortblocks for the future and it sounds like a box of rocks from the engine bay.lol

Car has 53k on a 2015 camaro ss. It has about 2300 miles on a heads, cam swap from gpi, almost a 1/4 of those miles are from drivingback from gpi in Arkansas to Houston in May. Haven't goosed the car for about 1k miles so whatever it is is sudden. I have oil pressure and and oil is full. Smells clean and good color.
My brother who is a former mechanic is coming over after he gets off work tomorrow morning. He is a firefighter and he is going to check it out but it definitely doesn't sound good. Did it out of nowhere. Thoughts?

bsn · 11-11-2023, 03:43 PM

Maybe failed rocker or collapsed lifter, doubt its anything terminal.

ss camaro-monte · 11-11-2023, 04:01 PM

That is what my brother was thinking. He was thinking valve train related but we will see. He is going to come over and see if he can figure out if it is the top half or bottom half or even if it is the engine. Doesn't matter if I am in gear, park, or neutral. You can hear it. Cam isn't very big but does have a lot of lift. over 600 on both intake and exhaust but is mild as a performance cam goes. 216 228 118 lob separation. Has the CHE package and appropriate valve springs from when GPI installed it and the GM performance parts caddy lifters.

I have had a motor with a rod knock before and it doesn't sound the same from what I remember. Rod knock sounded lounder and like a hammer hitting. This is more like a box of rocks moving in the engine or clunking. It isn't high pitched either. When my brother comes over I will record it and post it if I can. Want to start it as little as possible until I know what it is but it has oil, pressure and good oil. It is full with the driven 5w 30 ls motor oil GPI filled it with still and isn't low or dark. Oil looks good.

AlisoBob · 11-11-2023, 07:14 PM

"Box of Rocks" sound is usually a main bearing failure. Hope you find otherwise.

Could also be a broken flex-plate.

Good luck

ss camaro-monte · 11-11-2023, 07:19 PM

All I can say is if it is the bottom half of the motor it is going to get forged if I have to pull it with a stroker crank. If it turns that way.lol

ss camaro-monte · 11-12-2023, 05:02 PM

So I didn't get to record it but there isn't really a way to tell what it is without maybe a stethoscope. At first my brother thought it is from the bottom end but we both agree it sounds closer to the front of the motor. Possibly something with a pulley or tensioner but it is also a noise he hadn't heard before. Doesn't sound like a rod knock or any valve train noise. It's more like a box or rocks or maybe rolling or scraping of metal.lol

We aren't going to start taking it apart. I am going to see if a local company will check it out on Tuesday and have it towed there.

One thing for sure is it doesn't really get faster or louder with more rpm. We revved it up a little and the speed and loudness of the noise didn't change much. This is why we don't think it is valve train or at least springs. Definitely isn't a ticking sound.

Let you guys know later in the week what we find out.

joshnmn · 11-12-2023, 05:18 PM

Does it have A/C? I've heard bad compressors that sounds like a bunch of rocks.

ss camaro-monte · 11-12-2023, 05:40 PM

Yes it has AC but the compressor isn't on when we start the car.

ss camaro-monte · 11-12-2023, 05:49 PM

If it is the bottom end. Thinking of something like this but that is getting way ahead of myself.lol

https://cnc-motorsports.com/k1-405-l...e-pistons.html

https://cnc-motorsports.com/eagle-41...p-pistons.html

bsn · 11-12-2023, 06:13 PM

If it is not RPM related that's good, I have a hard time believing your bottom end would be hurting after 50K miles. Never heard of main bearings sounding like a box of rocks when they fail + you would have little to no oil pressure with a failed main bearing. Any chance you have headers and a leak???

Pkeen · 11-12-2023, 07:09 PM

Yea,just go ahead and stroke it ,you won't regret it !

ss camaro-monte · 11-12-2023, 07:13 PM

I don't know I've had header and exhaust leaks before but they never sounded like that it sounds like someone took a bolt or a nut stuck it in the motor and it's moving around inside kind of like that or that something is rotating with possibly making contact but that's all just a guess I'll find out more later this week. But it doesn't sound like a valve spring thing to me my brother's bent rockers and stuff before and he said that sure as heck is not a rocker but then again this is a very high lift cam even though the duration is minimal but again it's all just guessing it could be something crazy like a flywheel it could be the transmission who knows. But I'll know more later this week.

NiteProwlerSS · 11-12-2023, 09:18 PM

Did you try it with the belt off?

ss camaro-monte · 11-12-2023, 09:25 PM

No I didn't but the thought that it could be a tensioner or pulley is something I thought about. If I have time after work tomorrow I will look at that.

11-11-2023, 03:04 PM	#1
ss camaro-monte Drives: 2015 camaro 2ss, 87 monte ss Join Date: Jun 2016 Location: Houston Posts: 304	Engine bay sounds like a box of rocks Well started the car today and I think this is crazy because I was just asking about possible shortblocks for the future and it sounds like a box of rocks from the engine bay.lol Car has 53k on a 2015 camaro ss. It has about 2300 miles on a heads, cam swap from gpi, almost a 1/4 of those miles are from drivingback from gpi in Arkansas to Houston in May. Haven't goosed the car for about 1k miles so whatever it is is sudden. I have oil pressure and and oil is full. Smells clean and good color. My brother who is a former mechanic is coming over after he gets off work tomorrow morning. He is a firefighter and he is going to check it out but it definitely doesn't sound good. Did it out of nowhere. Thoughts?

11-12-2023, 07:09 PM	#11
Pkeen Drives: 2010 Camaro 2ss/rs, 2008 Avalanche Join Date: Jan 2019 Location: Lake Pannasoffkee,Florida Posts: 293	Yea,just go ahead and stroke it ,you won't regret it ! __________________ 2010 Rally Yellow 2ss/rs , M6 ,416ci , K1 rods & crank,weisco -3.0cc dome pistons,.040 head gasket, 11.5 compression,1 3/4" LT ,3" pipes w/x-pipe no cats, Cam Motion cam 239/247 113+3 .621"/604" lift , BTR .660 Platinum dual springs w/Titanium retainers, CAI . Stock ls3 heads,intake,injectors & TB. 515rwhp/500rwtq.

11-12-2023, 09:18 PM	#13
NiteProwlerSS Matt Drives: 2012 Camaro SS Join Date: May 2023 Location: KY Posts: 132	Did you try it with the belt off? __________________ 2012 Camaro 2SS LS3 M6

11-11-2023, 03:43 PM	#2
bsn Drives: 2013 ZL1 Join Date: Sep 2021 Location: Virginia Posts: 469	Maybe failed rocker or collapsed lifter, doubt its anything terminal.

11-11-2023, 04:01 PM	#3
ss camaro-monte Drives: 2015 camaro 2ss, 87 monte ss Join Date: Jun 2016 Location: Houston Posts: 304	That is what my brother was thinking. He was thinking valve train related but we will see. He is going to come over and see if he can figure out if it is the top half or bottom half or even if it is the engine. Doesn't matter if I am in gear, park, or neutral. You can hear it. Cam isn't very big but does have a lot of lift. over 600 on both intake and exhaust but is mild as a performance cam goes. 216 228 118 lob separation. Has the CHE package and appropriate valve springs from when GPI installed it and the GM performance parts caddy lifters. I have had a motor with a rod knock before and it doesn't sound the same from what I remember. Rod knock sounded lounder and like a hammer hitting. This is more like a box of rocks moving in the engine or clunking. It isn't high pitched either. When my brother comes over I will record it and post it if I can. Want to start it as little as possible until I know what it is but it has oil, pressure and good oil. It is full with the driven 5w 30 ls motor oil GPI filled it with still and isn't low or dark. Oil looks good.

11-11-2023, 07:14 PM	#4
AlisoBob Drives: Camaro 2SS Gen 5 Join Date: Oct 2023 Location: Orange County Ca Posts: 169	"Box of Rocks" sound is usually a main bearing failure. Hope you find otherwise. Could also be a broken flex-plate. Good luck

11-11-2023, 07:19 PM	#5
ss camaro-monte Drives: 2015 camaro 2ss, 87 monte ss Join Date: Jun 2016 Location: Houston Posts: 304	All I can say is if it is the bottom half of the motor it is going to get forged if I have to pull it with a stroker crank. If it turns that way.lol

11-12-2023, 05:02 PM	#6
ss camaro-monte Drives: 2015 camaro 2ss, 87 monte ss Join Date: Jun 2016 Location: Houston Posts: 304	So I didn't get to record it but there isn't really a way to tell what it is without maybe a stethoscope. At first my brother thought it is from the bottom end but we both agree it sounds closer to the front of the motor. Possibly something with a pulley or tensioner but it is also a noise he hadn't heard before. Doesn't sound like a rod knock or any valve train noise. It's more like a box or rocks or maybe rolling or scraping of metal.lol We aren't going to start taking it apart. I am going to see if a local company will check it out on Tuesday and have it towed there. One thing for sure is it doesn't really get faster or louder with more rpm. We revved it up a little and the speed and loudness of the noise didn't change much. This is why we don't think it is valve train or at least springs. Definitely isn't a ticking sound. Let you guys know later in the week what we find out.

11-12-2023, 05:18 PM	#7
joshnmn 2&THEHIT Drives: 5th Gen Camaro; 5th Gen Ram 3500 Join Date: Mar 2018 Location: Garner, NC Posts: 1,102 View My Garage	Does it have A/C? I've heard bad compressors that sounds like a bunch of rocks.

11-12-2023, 05:40 PM	#8
ss camaro-monte Drives: 2015 camaro 2ss, 87 monte ss Join Date: Jun 2016 Location: Houston Posts: 304	Yes it has AC but the compressor isn't on when we start the car.

11-12-2023, 05:49 PM	#9
ss camaro-monte Drives: 2015 camaro 2ss, 87 monte ss Join Date: Jun 2016 Location: Houston Posts: 304	If it is the bottom end. Thinking of something like this but that is getting way ahead of myself.lol https://cnc-motorsports.com/k1-405-l...e-pistons.html https://cnc-motorsports.com/eagle-41...p-pistons.html

11-12-2023, 06:13 PM	#10
bsn Drives: 2013 ZL1 Join Date: Sep 2021 Location: Virginia Posts: 469	If it is not RPM related that's good, I have a hard time believing your bottom end would be hurting after 50K miles. Never heard of main bearings sounding like a box of rocks when they fail + you would have little to no oil pressure with a failed main bearing. Any chance you have headers and a leak???

11-12-2023, 07:13 PM	#12
ss camaro-monte Drives: 2015 camaro 2ss, 87 monte ss Join Date: Jun 2016 Location: Houston Posts: 304	I don't know I've had header and exhaust leaks before but they never sounded like that it sounds like someone took a bolt or a nut stuck it in the motor and it's moving around inside kind of like that or that something is rotating with possibly making contact but that's all just a guess I'll find out more later this week. But it doesn't sound like a valve spring thing to me my brother's bent rockers and stuff before and he said that sure as heck is not a rocker but then again this is a very high lift cam even though the duration is minimal but again it's all just guessing it could be something crazy like a flywheel it could be the transmission who knows. But I'll know more later this week.

11-12-2023, 09:25 PM	#14
ss camaro-monte Drives: 2015 camaro 2ss, 87 monte ss Join Date: Jun 2016 Location: Houston Posts: 304	No I didn't but the thought that it could be a tensioner or pulley is something I thought about. If I have time after work tomorrow I will look at that.