engine noise and oil ?

[knez]

I have 8.1l cc 25oohd it has what sounds like to me valve train noise on start up.I allways have dealer service it i think they use 10-30w.I'm thinking of doing it myself and was curious what oil any of you guys recommend for oil type and weight that would best help at least minimize the noise.It sounds like lifters pumping up but is progresively getting worse have heard the csk cause my last truck had it 5.7l and this souds different but i could be wrong.Any help would be appreciated

[Haulin' 8.1]

I recommend the specified 5W-30 oil because it pumps faster cold and reduces pressure lag time at start-up. Also use a high quality oil filter with a silicone anti drain back valve. Hint-- if the filter is orange don't pick it. A Delco, Wix, Motorcraft, Purolator, will do fine. Those with no or cardboard anti-drainback valves don't hold oil the the pressure side when the engine is shut off and this easily causes valve clatter on restart. I wonder what your dealer has been using?

 

Vernon

[firstruck]

"this easily causes valve clatter on restart."

 

Humm.. valve clatter, thats exactly the sound my 6.0L makes in the morning when I lift off the gas under load, it sounds like a box of marbles in the engine. Probably not hurting anything but it is annoying and a weee embarassing. It does go well with my CSK and they clear up about the same time( a few minutes). So, is the oil pressure the cause?, clogged cats(2 much back pressure?), engine cold timing off a bit? lifters not pumped up? No biggie but I could effect the cure if I knew what it was..

[knez]

firstruck yea mine does same thing when letting off gas mine allso has marble in the engine sound until warmed up mine only has 16k bought it brand new it is just a little embarasing when you buy a 40 thousand dollar truck and at start it up sounds like the engine screwed up.Don't get me wrong i love the truck.Just annoying. HAULIN 8.1 so you think the oil filter could be part of the cause?I dont know what dealer uses I'd like to think they use a descent filter anyhow thanks for the replies. KNEZ

[Guest LeeR]

What you all describe sounds like the infamous PISTON SLAP problem.

 

Go to

www.#####.com and play the audio

 

Piston slap is where the piston rattles around in the cylinder.

[Guest LeeR]

go to www

 

pistonslap

 

.com

[knez]

LeeR I hear ya but I can drive my truck for an hour turn it off for 15 min and start it up and it will make the noise for about a minute.Im imagining until lifters pump up like i said in first post I could be wrong But seems to me once engine is warm It shouldn't have noise . csk= cold start knock jmo

[Haulin' 8.1]

A short clicky rattling that is just at first startup will be lack of oil pressure which could have many causes, or a bad lifter that bleeds down without constant pressure. The contsant clacking that muffles down or goes away once the engine warms up would be the piston rocking issue known to most here as "piston slap".

 

Vernon

[gjr]

A short clicky rattling that is just at first startup will be lack of oil pressure which could have many causes, or a bad lifter that bleeds down without constant pressure. The contsant clacking that muffles down or goes away once the engine warms up would be the piston rocking issue known to most here as "piston slap".

 

Vernon

 

 

Ok i know old topic. But my 5.7 vortec in my 99 burban just started doing this and the odometer just hit 156k. My concern is it started with no warning. Right at oil change time the knock the best i can describe it started and it is very loud but it only lasts for about 10 seconds when i start it. It happens when its cold and after its been off for about 10 minutes. No other noises when its running though. If its a lifter as i suspect should I change them now...and if i don't can it hurt the motor? I am only concerned because the motor does not use a drop of oil between changes and still runs like the day I brought her home from the dealer so I would like to keep it that way.

 

Thanks in advance for your help and opinions.

 

 

p.s. Since new i have used 5-30 and 10-30 valvoline winter and summer.

[REV353]

My 8.1 makes or maid the same type of noise, I would say it sounds more like the timing chain noise in my 65' Fairlane. Being mine takes some oil like most of them do, I went with a 10w-30 XL Amsoil here in the spring to see it that slowed it down, now after reading this, I haven't noticed that start up noise or anything I use to. I will have to pay more attention to it the next time I drive it. I normally use amsoil's ASL 5w-30

 

What kinda MPG are you getting? I'm up to 8-10 pulling and 11ish to 12.9 normal driving.