Lifters, piston slap, or normal?

[thompsoj22]

Thank you.

Yeah I spent the extra money on "GOOD" parts to avoid this crap.

The truck runs great, it's very fast for it's size nearly in the 4's 0-60 which is insane. But my primary use for this truck is a cold start, drop son off 10 mins away, back in the driveway. It won't quiet down until I am about to shut it off for the day.

Here it is completely warmed up and it sounds perfectly fine.

If it were me, My first swap would be the "HI PERFORMANCE" springs for oem's. Eliminate the static downforce which is probably collapsing the lifters as it sits overnight. This can be done with the compressed air technique or a tried and proven method of bringing the piston up about two thirds of the way, Feed 3/8 nylon rope into the chamber through the sparkplug hole until it stops, Then bring the piston up til it is firm and stops. You can now compress springs remove retainers and swap in oem and retainers, Then rotate the piston down slightly and remove the rope and on to the next. I swear this works fantastic, The reason for the nylon rope is no fibers from other choices like cotton/hemp.

 

[donjetman]

This can be done with the compressed air technique or a tried and proven method of bringing the piston up about two thirds of the way, Feed 3/8 nylon rope into the chamber through the sparkplug hole until it stops, Then bring the piston up til it is firm and stops. You can now compress springs remove retainers and swap in oem and retainers, Then rotate the piston down slightly and remove the rope and on to the next. I swear this works fantastic, The reason for the nylon rope is no fibers from other choices like cotton/hemp.

I use an old long spark plug wire with one of its ends cut off instead or rope.

 

[ls1frc]

I can't put OEM springs in, my cam has .600 lift.

What I am going to do is swap in stock lifters and my stock cam. That is the only way to know for sure.

Are these Delphi lifters still ok? I am not spending $350 on LS7 lifters. If the Delphis are suspect, I'd rather just try out the used lifters I have sitting in my garage from the old engines.

**Edit**

Got some info on some of the lifters out there, no good if it's AC delco ones.

https://ls1tech.com/forums/generati...er-differences-hl124-12499225-17122490-a.html

 

[ls1frc]

In your opinion do these sound the same?

 

[wsteele]

In your opinion do these sound the same?

They sound the same to me (origin wise), the Escalade sounds louder though. Sounds like lifter tap to my untrained ear.

 

[Geotrash]

In your opinion do these sound the same?

+1 to Bill's comments. The frequency and timbre of the rapping sound are the same. The difference to my ear is in the loudness relative to the background noise of the exhaust, cooling fans, etc. The Escalade is louder from a greater distance. Both sound like a single lifter is the primary culprit. Time to pull those lifters and have a look?

 

[ls1frc]

+1 to Bill's comments. The frequency and timbre of the rapping sound are the same. The difference to my ear is in the loudness relative to the background noise of the exhaust, cooling fans, etc. The Escalade is louder from a greater distance. Both sound like a single lifter is the primary culprit. Time to pull those lifters and have a look?

I am going to overhaul the entire thing and replace both the cam and lifters so I don't chance it, but I didn't wanna waste my time if it was just piston slap. This was the first video where the original poster said the dealership replaced his lifters and cam.

I am getting this noise even after the truck sits only for 2-3 hrs in 90 degree weather. That doesn't scream piston slap to me. I start it up and the coolant temp is like 160 and still makes it. Goes away after 5-10 mins, but the valvetrain is still noisier while driving than I experienced in other setups.

I forgot from your build, but did you go with the Morel dropins? I had them in the 5.3 and the engine sounded great.

Since cams take so long to ship now, I may just do new lifters and the used stock cam for now. I don't want to put new lifters on the current cam because who knows if the current cam is also a reason for the noise for some reason.

 

[Geotrash]

I am going to overhaul the entire thing and replace both the cam and lifters so I don't chance it, but I didn't wanna waste my time if it was just piston slap. This was the first video where the original poster said the dealership replaced his lifters and cam.

I am getting this noise even after the truck sits only for 2-3 hrs in 90 degree weather. That doesn't scream piston slap to me. I start it up and the coolant temp is like 160 and still makes it. Goes away after 5-10 mins, but the valvetrain is still noisier while driving than I experienced in other setups.

I forgot from your build, but did you go with the Morel dropins? I had them in the 5.3 and the engine sounded great.

Since cams take so long to ship now, I may just do new lifters and the used stock cam for now. I don't want to put new lifters on the current cam because who knows if the current cam is also a reason for the noise for some reason.

Yeah, something is wrong. Piston slap is at 2x lifter frequency anyway, so that would seem to rule it out.

Yes, I used the Morel 6504 drop-ins.

Looks like Brian Tooley has the same cam I used in stock. https://briantooleyracing.com/btr-camshaft-gen-3-4-truck-stage-2-v2-btr31218110.html

You'd lose the VVT but I haven't missed it at all. Great lope and power.

 

[ls1frc]

Yeah, something is wrong. Piston slap is at 2x lifter frequency anyway, so that would seem to rule it out.

Yes, I used the Morel 6504 drop-ins.

Looks like Brian Tooley has the same cam I used in stock. https://briantooleyracing.com/btr-camshaft-gen-3-4-truck-stage-2-v2-btr31218110.html

You'd lose the VVT but I haven't missed it at all. Great lope and power.

Yeah that's a great point about the 2x frequency, didn't even think of that.

Another thing I can do is get the lifters out first, then make a decision on whether the cam should come out as well based on how they look as well as the cam lobes.

 

[ls1frc]

Ok so I ordered my parts.

-Morel 7717 dropin lifters. Had the 6504 in the 5.3, but these are apparently just new revision.
-New true GM trays.
-Arp head bolts
-Mr Gasket .040 gaskets
-Brand new STOCK vvt camshaft

I will reuse the PAC springs, nothing wrong with those and that has nothing to do with noise.

My thought process on going with stock camshaft.
1) The ones in stock at BTR are too rowdy, I really like a lot of negative overlap in a daily truck. Don't want any lope. Only thing that would give me no lope is the stage 1 truck cam, which is too small for a 6.2 and pushes the powerband down too low.

2) This will rule out any doubts. If it still makes noise with brand new lifters and brand new stock cam, then I know I've got a problem with the bottom end and I don't really wanna invest anymore into it anyway. I inspected my used stock cam and didn't like the marks on it.

3) I could have ordered another cam motion VVT cam, but they're over a month out. I don't want to risk this noise shedding metal into my bearings, so I wanna get it done before it gets super hot out.

I am treating it like $100 diagnostic essentially.

I will report back once I am done. If all the noise is gone, I will send back my existing cam to cam motion and have it re polished and probably just throw it back in.

If noise is still there, then I will just drive it until the engine goes.