Finally!!!! My rebuilt 2002 LS1 on dino Halvoline 10w30, 2,389 miles on oil.

[Chris B.]

Ok some of you might remember about 4 months ago at 12,000 mile the local Chevy dealer agreed that my LS1 was knocking to much and did a full lower end rebuild, new pistons, rings, berings ect. My LS1 is still very noisy and sounds like a diesel on a hot start up but not a cold start up. The knocking does go away 100% after a minute or so. I think the oil consumption is gone because in the last OCI (2,389 miles) it droped very little on the dip stick and took only a few oz to top off so it might have been that low to begin with and I did not catch it. This run included several WOT runs to help seat the new rings, I floored it hard many times!
The car feels very strong and runs like a champ.

Rebuilt at 12,000 miles and used Halvoline 10w30 for re-break-in changed at rebuild to 500 miles(12,500) changed again at 13,550 and back to Mobil 1 10w30/Lube control at 15,939. Total miles on Halvoline 10w30 was 3,939 miles. Engine sounds the same on the 2 oils and oil pressure is the same also.

This UOA/ last UOA on M1 5w30 and 3,000 miles (10,366 total miles on engine)

Aluminum 2/3
Chromium 1/1
Iron 9/16
Copper 52/118 Huge drop!!!!
Lead 4/8
Tin 3/3
Molybedenum 65/68
Nickel 0/1
Manganese 1/0
Potassium 2/0
Boron 119/157
Silicon 37/14 probibly from rebuild sealents.
Sodium 2/9
Calcium 2174/3397
Magnesium 27/17
Phosphorus 782/709
Zinc 920/933

SUS Viscosity @210 degrees 56.7 Thinned to a 20w

Flash point 380

Fuel
Antifreeze 0

Water 0

Insolubles 0.3

TBN 4.2 Halvoline starts at 5 or 6

I'm very happy with this and shows the Tech did a solid rebuild! The wear is dropping great even with about 600 miles less then the last OCI it shows better wear. I hope the Mobil 1 10w30 shows this good or better this next time around.

It makes me wonder, the Halvoline thinned to a 20w but wear is still good. Maybe this is more evidence that thin oil will protect this engine as good or better then a thick oil?????

[ December 08, 2003, 03:35 PM: Message edited by: Chris B. ]

 

[Drew99GT]

Looks good. After you are totally confident in the rebuild, I'd bring that Tech a case of beer!

 

[Last_Z]

Chris B,
Good report!
Explain something to me....you state there is NO sound at all after a cold start, but there is a sound on a hot start. Is this piston slap sound or lifter clatter? Is there ANY noise at all while idling at normal temp.?
My 02 Z28 does not slap on a cold start unless you drive away....after a couple of minutes, it won't slap, even if you drive it. It does have this noise, like a diesel (like yours I guess) when the car is warm. It sounds as if it's low on oil. I'm trying to figure out if we have the same problem.
My car also runs very good. With a lid and FRA, I got a best of [email protected] the power is there.
Rick

 

[Last_Z]

One more thing Chris.....I'm currently running the GC stuff and the noise is still there. No change whatsoever. Hopefully wear will be good with it.

 

[Al]

Glad things worked out

 

[Chris B.]

I like Halvoline but It thins out way to fast in this engine and I only used it for re-break-in. I'll see how the Mobil 1 and LC work and if wear is not low like this after 2 or 3 UOA's then time to change oil.

One of the reasons I use M1 is because it is very stable and it will keep my engine spotless especially with the LC and then engine sounde the same on it then other oils.

 

[Chris B.]

quote:

---

Originally posted by Last_Z:
Chris B,
Good report!
Explain something to me....you state there is NO sound at all after a cold start, but there is a sound on a hot start. Is this piston slap sound or lifter clatter? Is there ANY noise at all while idling at normal temp.?
My 02 Z28 does not slap on a cold start unless you drive away....after a couple of minutes, it won't slap, even if you drive it. It does have this noise, like a diesel (like yours I guess) when the car is warm. It sounds as if it's low on oil. I'm trying to figure out if we have the same problem.
My car also runs very good. With a lid and FRA, I got a best of [email protected] the power is there.
Rick

---

LastZ, when I start her up in the morning it sounds smooth and has no slapping noise or ticking(mine sounds like a diesel) then after a minute or less of warm up it will start(the diesel sound) when I drive off I can't really hear it inside of the car but it is gone after the engine is warmed up from driving. When my wife drives up in it I listen to the engine befor she turns it off and it sounds like a normal engine. Then we turn the engine off and wate maybe 10-20 minutes and restart and the diesel sound is there immidietly but fades in a minute or so.

I have never really heard and been given a car with piston slap right in front of me to listen to so I only know what piston slap is by reading up on the web about it and then listening to my engines. On the web sight www.pistonslap.com they have a sound clip of a GM engine with slap and mine sounds just like that bun not as bad. I'm just going to drive her and hopt to hit 200,000+ miles which with this wear I feel I can do that.

 

[Last_Z]

ChrisB,
My car sounds just like the one on that website. We have the same problem, the only difference is that mine does not go away. It is very very noticeable, exactly as the audio clip on pistonlsap.com
I'm waiting on Terry's comments and suggestions.
Rick

 

[Last_Z]

Chris,
For some reason, I do not thik we are experiencing the piston slap. I think it has something to do with the valvetrain, specifically the lifters. Someone mentioned at LS1.com something about noisy fast bleed lifters, but couldn't remember if the guy was referring to stock or aftermarket lifters.
I have two very different sounds.....like I mentioned before, upon a cold start, the engine makes no abnormal sounds at all....if you drive off however, there is a distinct slapping sound. I believe this is the piston slap. It goes away after driving only half a block. The other sound arrives after 30 seconds to a minute after start up and never goes away.
One thing I have noticed though, I have a 160* T-stat and the engine run fairly cool all the time; when the engine gets pass the 210* mark, the ticking/diesel sound goes almost completely away. This has me wondering if my engine is running too cool and/or the lifters or pistons or what have you need to be really hot in order to run good?

EDIT:

quote:

---

Ok some of you might remember about 4 months ago at 12,000 mile the local Chevy dealer agreed that my LS1 was knocking to much and did a full lower end rebuild, new pistons, rings, berings ect. My LS1 is still very noisy and sounds like a diesel on a hot start up but not a cold start up.

---

Chris, are these the "new" design piston? If so, this could prove my theory of bad/noisy lifters, not bad pistons

[ December 09, 2003, 10:25 PM: Message edited by: Last_Z ]

 

[Terry]

Z, I posted under the GM Piston slap thread. Please post the results I sent you if you want. I think the lifters may be a issue here that I haven't seen before. I am willing to discuss both of these results publicly if you and Chris want to engage that. The dieseling issue is a new one and only you two have mentioned it, other customers have had only the lower end of block noises.

Patman do you have anything to share on the valvetrain side from your insider info?

[ December 09, 2003, 11:20 PM: Message edited by: Terry ]

 

[Alan]

You might just get lower wear numbers by sticking with the Havoline.

Cheaper to boot!

 

[mikep]

quote:

---

Originally posted by Alan:
You might just get lower wear numbers by sticking with the Havoline.

Cheaper to boot!

---

You read my mind.

Mikep

 

[Chris B.]

Rick, I read on LS1.com that GM was working on replacement pistons to correct the slap. Dealers were supposed to get the newly designed pistons last summer. I believe this is what I got. The replace a bunch or other things as well. If you like I'll get the RO recept and list all of them.

Terry I would love to figuer this "diesel" thing out. I don't really know how a drivetrain works and how timing works but anything I can do to help out would be great. I love to learn! I wish we could get the 2 cars next to each other to compair and lister to exactly what knids of sound is coming from the engine.

 

[Patman]

quote:

---

Originally posted by Terry:

Patman do you have anything to share on the valvetrain side from your insider info?

---

I've not heard of any problems with the valvetrain causing noises in these engines actually, this is the first time I've heard that idea mentioned.

 

[Terry]

We all need to thank motorbike

, for posting what I think is A key to the LS1 noise issues.

That is the cam driven oil pump cavitation causing interupted oil pressure to the mains and the resultant upper engine valve train sounds.

Both Chris and Rick have new engines that I have enough data on to compare and correlate fairly accurately. Revealing a NEW issue of the dieseling sound which I think is the very early indication of this oil pump cavitiation. I think the frequency of the cavitation is fairly high with short duration thus the pressure readings look fine until we have wear issues that compound the interupted oil flow. The lifters are talking to us.

Those that drive the LS1 gently ( rare) MAY see this less and combine that with an inherent engine imbalance from production we may have our cause and effect for the the low end noise that may be contributing and simultaneously masking this issue.

This is a low friction engine setup and if my THEORY is correct is a testament to the bearing construction of the LS1 if interupted oil flow/pump problems is the primary issue.

These 2 guys are the first customers to report dieseling or a suspected lifter/oil pressure issue. Any others ?

Any LS1 members have a aftermarket or modified oil pump with UOA's for us to compare too ?

I'm not a engine builder so help me out if you are.

Once again thanks to Moto for your contribution !

[ December 10, 2003, 11:39 AM: Message edited by: Terry ]

 

[Last_Z]

Terry,
One thing I've been meaning to tell you but keep forgetting; there is NO ticking or diesel sound when the engine is loaded; only at idle and deceleration.

This is what the sound is like.

Rick

 

[Terry]

Z,

That fact is consistant with Chris's comments and indicates the indexing and engagement of the pump itself is causing problems at low rpm, low load initially.

IF we had high load issues the engine would crater fast and this problem would be fixed by GM, QUICK.


Thanks for the link to the sound. That does not sound like piston noise but lifters but without a stethoscope I can't be sure. My hearing is not good anymore anyway.

 

[Chris B.]

Thanks Rick for the link. That is what my engine sounds like but not that defind or loud but deffinetly that sound!

 

[Drew99GT]

The sound both of you describe sounds like classic piston slap. The way you describe it sounds exactly like my 99 Grand Am GT; it's kind of a rythmic clacking sound, where as lifter and valvetrain noise is more of a sharp ticking sound. And my Grand Am would start doing it about 15 seconds after start up and just gradually get louder for about 2 minutes then fade away as the engine warmed up. My car was worse on startups after the engine had already been up to temp then cooled down for about 2 hours. In those situations, it was devestatingly loud and numerous people would comment that my motor sounded sick.

 

[Chris B.]

Drew, that is almost how my car acts.