5.3 GMC vibration / shuddering

NoBrakes!

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We run the Joe Gibbs Driven LS30 oil, seems to hold up well at rpm. no AFM though
 

Stg2Suby

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Just reading up on that AFM active fuel management and the special hardware lifters, cam, solenoids etc. that goes with it. Not sure I'd want it although it is supposed to give 5-7% mileage increase when in 4 banger mode. Haven't heard an update on the truck other than it is supposed to be covered under warranty.
 

ABMax24

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I still think it's the cause of the cam-lifter issues

That 0w20 oil is piss water cold and even thinner hot

The 5.3's with active fuel management had cam issues before the oil was switched to 0w20 in 2014. I can see oil being a factor but I know a few people with pre 2014's that had the valve train components replaced as well. I think it's a poor design, besides shutting off 4 cylinders on the highway improved economy what? Maybe a few percent?
 

tex78

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The 5.3's with active fuel management had cam issues before the oil was switched to 0w20 in 2014. I can see oil being a factor but I know a few people with pre 2014's that had the valve train components replaced as well. I think it's a poor design, besides shutting off 4 cylinders on the highway improved economy what? Maybe a few percent?
The 5w30 back then is also energy conservation oil, which is most of the issue too


It uses oil to unlatch the lifter, which the zinc in the oil ( zddp) is the barrier of metal to metal

But it takes energy as it restricts
 

ABMax24

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The 5w30 back then is also energy conservation oil, which is most of the issue too


It uses oil to unlatch the lifter, which the zinc in the oil ( zddp) is the barrier of metal to metal

But it takes energy as it restricts

All manufacturers are limited by the same maximum amounts of ZDDP engine oil, but it does seem that those with AFM, and to some extent MDS in the Dodges that have issues.

But I would be curious to know what they do in Japan, they are limited to 0.05% Phosphorus where we can run 0.8%, which is the element that limits the amount of ZDDP than can be added to the oil.
 

NoBrakes!

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Can you order the 5.3 or 6.2 without the AFM? or would you need to change out the problem parts after warranty?
 

MK4TDI

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You can get a tune to disable it from Blackbear tunes
I had blackbear tune 2015 5.3 way better truck to drive,removed AFM, adjusted speedo for new tire size, and a trans tune...

I've read mixed results on the tuning the AFM out on the 6.2, some still have troubles and some dont. I think if I was to get the 6.2 I would get ahold of Texas Speed and use their cam and lifters to delete it..
 
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