I was just wondering if its ok to switch back from Royal Purple to conventional..I only had it in for...less than 30 miles now..and its knockin at idle..I cant seem to hear it at higher rpm or in the cab while driving but the motor seems to be running a hair hotter...I just thought synthetic oils the way to go..its 5w-20 just same as the conventional I put it..

Im gonna go to the dealership tomorrow and ask them to look at it...and ask their opinion on what the noise is. Seeing as its my only truck,cant afford a new engine,and I owe a ton of money on it and cant afford to let it go to hell,I want to fix it before its broke.. If you were to take a glass marble or something..and lightly tap the block,thats what it sounds like.

 

WHether it's more apparent or not? Or you just noticed it more now than before?happens alot..switching back is no problem, but I'd say your wasting money for both this dump and the refill. Mine makes noise too, but synthetic will protect against wear better than conventional so regardless of what's going on in there, your synthetic is still going to outperform the regular stuff.

 

+1. knocking is never caused BY and oil change. Theres something else going on in there. Take it in and have them look at it.

 

You make a good point there...Ive hear lifter tick...atleast on my dads 2001 Chevy silverado..sounds terrible at cold start up...click click click click...lasts a minute then goes away...but,this seems to be coming from down below

 

Yeah, my '00 Silverado 4.8L sounded like a bunch of rocks shaken in a coffee can upon start up and quickly go away, but on low idle conditions the tapping would sound like knocking because it was an all aluminum engine. Aluminum amplifies the sound.
GM said it was piston slap. Little combo of slap and lifter tap.

Mine, the tick/knock if you will sounds strong under the driver door and from the driver side front, but as soon as you move towards the pass. side, the noise dissapears. The noise can be even heard inside the cab. If I give it gas and bring the rpms up to get the oil pressure up and flowing, the tapping goes away.
I would rather deal with the slight noise than have my truck and engine all torn apart for a possible fix. i doubt your noise is coming from down below. The noise is prolly just being deflected around in the engine bay.

 

Are we sure it's not the hemi "tick" Not much you can do about that I'm gonna try motorkote on my next oil change and diff change gonna try the power steering as well.,

 

My 6.0 Silverado sounded lovely (Sarcastic)


My Hemi ticks very lightly if I let it idle while warming up. Instead, I just drive softly for a few miles and once warm.....I never hear a tick.

Leave the oil and don't idle your truck cold or while warming. Drive it nice and easy and you'll never hear it...

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