Kennyray
Full Access Member
My truck has the 5.3 with the iron block. Since I'm new to this engine style, is that better than 5.3 with the aluminum block or are they pretty much equal?
'08 5.3
- Thread starter Kennyray
- Start date
Most of the oil consumption issues with the Gen IVs that I've seen on the net are on the aluminum blocked engines.
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Kennyray
Full Access Member
Well that's good to know....
Thanks fellas 
Thanks fellas 
Turn off AFM unless your truck has had the oil consumption TSB fix.
turn it off, even if it has. That "fix" is a joke.
I have yet to hear anyone have excessive oil consumption after the TSB fix, or on newer models with AFM.
Back when this TSB came out around 08/09, the fix worked somewhat for some people, and very little or not at all for others.
It is a "mist deflector" to try to prevent the oil mist from entering the combustion chamber. How well do you think a small piece of sheet metal is going to work?
Of the people I know that had the problem, it was solved with the TSB.
Myself, I just disabled AFM... No change in fuel economy for mine.
Myself, I just disabled AFM... No change in fuel economy for mine.
Small pieces of metal are pretty effective at deflecting oil coming out of a PRV. Looks like it completely blocks the side ports on it causing it to just hit the wall and fall back into the oil pan. I believe the TSB also includes a new left valve cover with a relocated PCV drain hole, and cleaning or replacing the piston rings.
I wouldn't worry too much until you see if it's actually consuming oil. There's three 08 iron block 5.3s in my family and none of them consume oil and all of them still have the AFM functioning.
Power lock actuators are a different story...
I wouldn't worry too much until you see if it's actually consuming oil. There's three 08 iron block 5.3s in my family and none of them consume oil and all of them still have the AFM functioning.
Power lock actuators are a different story...
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