stevenc

iTrader: (1)

So yeah..

My 4.8 running royal purple had quite a bit of oil consumption 160K miles.

I swapped in a 5.3 with 45k miles, still running royal purple, and I am seeing a 1.5 qt loss at 2k miles.

I do alot of stop and go traffic driving.

What about you guys?

joeyc125

iTrader: (7)

i had the same problem. I found i had so much vacuum in my crankcase it was sucking oil/vapors through the intake. It would literally suck the oil cap on when you try to take it off. I restricted my breather line to the intake to about an 1/8" hole and my oil loss went away completely. I would use probably a quart every 1000-1500, now i lose none. Maybe not your problem but its worth checking out.

stevenc

iTrader: (1)

Good idea! I'll check that out.

budhayes3

iTrader: (19)

The LS style engines are known for oil excessive suction through the PCV system. Do a search for "catch can" and you should find a good solution for what may be the cause of your oil consumption problem, that will leave the PCV system intact and functioning as it should

white lightning SS

iTrader: (3)

There are supposed to be new design valve covers available to allow splashed oil to drain from the valve cover baffles to keep it out of the PCV system. I am putting a set on a G8 this week. I'll let everyone know what they look like soon.

budhayes3

iTrader: (19)

Very cool, I hope that they work, I'd buy a set of those

SBTork

iTrader: (5)

that sounds like a solid idea, keep us posted

GMCtrk

iTrader: (27)

no oil consumption on my 143k mile 4.8 or my 82k mile 6.0

joeyc125

iTrader: (7)

my pcv system still works fine, it was just sucking far too much in the crankcase, i just restricted it to an acceptable vacuum. I think a catch can is just band-aiding the problem of too large of a hose, and lack of a valve that would usually restrict the suction because of the smaller orifice inside the valve. I think a catch can is better suited for FI guys that actually have a problem with too much positive crankcase pressure, not too much suction.

budhayes3

iTrader: (19)

The fixed orifice PCV is supposed to be a fix for the oil consumption problem, my truck originally came with a traditional spring and plunger style PCV. Obviously, the fixed orifice PCV does not work, as I switched to one in my truck and got the same amount of oil in my catch can as I did with the original PCV.

Check the hose that goes from the PCV valve to the intake for the presence of oil. Before I got my catch can, I thought that I had one of the freaks that didn't consume oil either. When I checked the oil on the stick it was always in the acceptable range. After reading about the obviously flawed PCV design, I decided to investigate. Sure enough, my PCV hose was coated with oil.

I've always thought that maybe a better baffle system in the valve covers would be a good fix, maybe my thinking was right according to the info that white lightning SS posted about the re-designed valve covers. I wonder if they'll clear aftermarket rocker arms...