Engine Noise

[NWLakes]

2008 5.7 w/ 140,000 kms
I recently fell into the common assumption that my engine noise was due to warped and/or broken exhaust manifold.
Had the passenger side replaced but the noise continues( cold start up).
I was then told that my generation of hemi has some issues with front crank bearing not receiving proper oil which in turn causes knocking.
Can't afford this obvious repair cost.
Had the truck since 2010 and have had no other problems.
Body is in excellent shape so i'm not happy.

 

[Oliver Closehauf]

Does it only happen when it's cold and at start up? As in while the oil pressure is still low and now flowing?

 

[NWLakes]

Ya only at first start of day.
Quiets down after maybe 2-3 minutes.

 

[Dan98]

I'm guessing you have oil pressure long before 2 or 3 minutes?? Not to say pressure at the gauge means oil to all.

Sent from my SM-J260A using Tapatalk

 

[NWLakes]

Ya gauge is saying good pressure immediately. Using 5w-20 synthetic so should be good circulation but who knows.

 

[Oliver Closehauf]

So, if you can figure out how, disable the ignition and fuel pump, then crank it and listen. If its doing a thunk thunk thunk thunk in even time with a piston going up and down in the bore then that sounds to me like a sloppy rod bearing.

If it's doing a thunk....thunk......thunk......thunk, that sounds like a collapsed lifter that is taking a while to pump up and then bleeds down after sitting.

Maybe see if you can get a helper and do the socket extension stethoscope thing and see if you hear where its coming from.

 

[NWLakes]

Thanks for the suggestions.
I think i'll try to pinpoint better with the stethoscope for now.

I might also try changing oil viscosity to help with circulation but that's probably wishful thinking.

 

[Octane]

Put a bottle of lubeguard in it.