slimbobaggins

Wanted to update that after I posted yesterday, I found a video on youtube of another LS2 GTO that was making a nearly identical sound, and it ended up being a couple dead lifters, so I'm going to pull the heads off this week.

thendawg

Mine made the same exact noise as the last video posted. (Mines an LS2 GTO) I have a video too up on youtube. I busted my ankle up last weekend and could barely walk, or else the heads would be off by now. I have everything else off and ready to go. Should have the heads off and lifters out this weekend to confirm, but Im about 90% sure its a lifter. My only thing is, I know this motor has some miles on it (110k to be exact) and has burned a bit of oil, so if the bottom end isnt in great shape, the car may be down for awhile and start building it into a 402.

Heres the video of mine btw -

1967camaro78

iTrader: (1)

I work at gm and this is not that uncommon to see most of the time its on trucks and suvs with dod but should be covered under powertrain. I just replaced cam lifters and cam brgs on a 2008 truck with 80,000 was covered. I think the issue is camshafts are delaminating and take out lifters and cam brgs sometimes too.

thahemp

It has been a while since I checked my subscriptions here.

To both of you who posted videos. Both of you have lifter problems. Mine doesn't make that noise, but I have certainly seen countless piles of videos with the same sound, and it's always lifters. You guys both have some heads to remove unfortunately...

To the rest. Mine is an LS3 (hence the thread title ). It's a totally different chirping than the standard lifter chirp. It is still doing it BTW with no ill effect that I have found. It's a much higher pitched squeak and it only does it as the RPMs peak and start to fall, only under say 1200 RPM too. If I blip the throttle past 1200 RPM, it doesn't chirp at all.

I checked out the arcing possiblity. Unfortunately it was another dead end. I have started collecting parts for a cam swap. I'm going to pull the heads when I do the swap and check/replace all of my lifters just to be safe. Like I think I've said before... I suspect it's the actual roller on a lifter that is making noise. That's why I felt the need to inspect what cam lobes I could see with the IM off.

litle88

iTrader: (20)

That's a crazy squeak E!

I say just stock pile on your parts lol and you'll see what the beef is. It will be crazy if after a new cam and lifters the "squeak" still is going on lol.

thahemp

Hah! Yeah that would be crazy. I'd pretty much know for sure that it is something air related though... exhaust leak, valve event, maybe even just something wierd in the way my exhaust port flows out into the headers.. a burr or something.. who knows! My garage door squeaks too... maybe I'm just destined to have plenty of SQUEAK in my life.

GreenMeany94

I have a similar problem but its at and idle in gear and as soon as i touch the throttle it disappears........

thahemp

Is your car a manual? That sounds like a throwout bearing to me. If you depress the clutch does it go away?

thendawg

From his other post it looks like its an auto. With an auto, test in ALL gears, if it does it in P, N, R, D then that typically rules out the trans. My noise also seemed to go away under load and with rpm over 2000 or so, but its likely it was just drowned out by other valvetrain/exhaust noise.

GreenMeany94

automatic here is my post on it

https://ls1tech.com/forums/generatio...ash-whine.html

GreenMeany94

tried all gears still the same except neutral and park are higher rpm(only by a little like 200-300 rpm's) but the noise seems to go away after i step on the throttle. not being drowned out by other noise, i do know that part. does not chirp when it is cold only at operating temp. Does not seem to be any change in performance at all. This started to progressively get louder over a couple week period. I pulled the valve covers and the roller rockers all seem to be moving equally, i know there can be a slight difference in rocker travel not seen by the human eye. just not sure. i wanted to get some other input before process of elimination starts hahaha

thahemp

Well since it's an auto.. it's not the throwout bearing! Eliminate that one off your list. It could still be lifters. I think it's pretty common for that noise to go away under RPM. I think it's pretty common for the noise to start once the motor is warm too.

Engine noises can be very difficult to diagnose over the internet. That is what I have learned from my chirp experience so far. About all you can do is roll up your sleeves and check everything you think might be wrong. That's essentially what I have resigned to doing.

GreenMeany94

ok so i tried listening all over the place that i could with a stethoscope. Bottom of the oil pan very faint but i can hear it. Side of the engine block at No.1 cylinder, very strong sound. Valve cover at No.1 cylinder very strong. Still on valve cover sliding towards No. 7 stronger. Still on valve cover over the top of No. 7, ear piercing. So that would conclude it to be a lifter???

PlatnumStatuz

iTrader: (6)

Last time I heard a Tahoe with that chirp noise it needed a lifter

thahemp

I'd say you've gotten close enough to warrant pulling the head on that side and checking the lifters. Just remember... if you find 1 bad lifter... replace them all. It's a lot cheaper now than later... even if what you're in for now is more than you had bargained for in the first place.

slimbobaggins

Pulled my heads last week, and sure enough, the bearing in the #7 exhaust lifter was completely shot. I'm piecing together my L92 head upgrade now.

GreenMeany94

Im at the turn point found my problem guys. Remember i said the noise was louder the farther i went back on the vavle cover. Well number 7 exhaust roller tip rocker (bearing) was shot. Also number 5 intake was the same. But riddle me this why would i pull the head to get to my lifters when thay are clearly visible and removable from the valley of the block. I'm just curious... But i do appreciate all of the help from the folks here at this forum and i will recommend this place to all. Also i did check the lobes of the cam with my snake camera and the lobes seem to be ok as well the lifters too. I would like a recommendation however as to what type rockers to get. The one i have are PRW 1.6 steal with roller tips. It says "C36" on the under side of the rocker Thanks again you guys for the help

thahemp

You may not have to pull your heads. I missed what motor you're running. I have an LS3. I have to pull my heads to get to the lifters. You should probably start a thread specific to your motor to get input on what rockers you should run. You'll get a lot better coverage than a thread with LS3 in the title .

thendawg

I got the pass side head off today, unfortunately didnt have time to pull the driver side (only had a couple hours to work on it today). Already found one bad lifter/cam lobe, you cant tell too well in the pic, but in addition to the pitting it also has a pretty decent flat spot on it.

thahemp

Dang. Have you changed your oil recently? You should change it and cut open your filter. You might have metal in your engine...