"over-active" Lifters On Smoking 2009 Silverado 5.3l Afm

jnpaddison · January 5, 2010

07 5.3 with afm - 20k - periodical tapping at start up with '76' full syth ,, currently has Penzoil full synth - no tapping so far ..

no blue smoke either

danc55 · January 5, 2010

My 2007 is consuming oil somewhere. I never get any smoke but after every road trip I am down a quart or two. It has been checked for leaks and I am on an "oil consumption study". I had been on one since last year but initial dealer was one that closed, so know new dealership is starting the study over. Glad my lease is up in April.

Neutron · January 5, 2010

My 2007 with 39,000 miles on it doesn't appear to have the issue, but does have an annoying rattle when accelerating in the lower RPMs. Sounds like it's coming from the passenger side of the engine compartment, and I have noticed my fuel economy has dropped 1.5-2 MPG since.

ColoradoSkiCountry · January 5, 2010

I had about 27,000 miles on my 07 with AFM and no smoking issues either.

trucc_boi · January 5, 2010

i get the annoying rattle as well.

cerbomark · January 6, 2010

i get the annoying rattle as well.

check the overflow tank on the passegers side. i had to put a piece of foam between the fender and tank to stop my 07 from rattling.

If you turned off the AFM would the oil useage stop with the guys having these issues??? Don t know? It might not help.

2009 LTZ · January 6, 2010

i get the annoying rattle as well.

check the overflow tank on the passegers side. i had to put a piece of foam between the fender and tank to stop my 07 from rattling.

If you turned off the AFM would the oil useage stop with the guys having these issues??? Don t know? It might not help.

Don't know, but the lifters might last longer if they are not being constantly engaged/dis-engaged for AFM??? It still may pump oil up into the intake... I'm turning my AFM off as soon as I get the truck back... If it then lasts for the 5yrs or 100K I'll be happy and I'll trade it for a 6.2L non AFM.

Ron

2009 LTZ · January 6, 2010

Hard to believe that I am the only one out there with this problem, but I may have just won the Chevy Lifter lottery. Would be my luck

Ryan00TJ · January 6, 2010

08 LY5 5.3L 8700miles. No problems. I'm at 37% on my 2nd oil change of M1 T@SUV 5W-30. What role do the AFM lifters have in pooling oil in the intake manifold? They have no direct connection to getting oil into the combustion chamber.

terrible1one3 · January 6, 2010

My dad's 08 5.3 with AFM has 68k miles on it and has no issues. Also his '08 Impala SS with AFM and 5.3L V8 with 62k miles has no issues either.

Matt09SLT · January 6, 2010

I have 11K on my 09 5.3. I've added almost 1 quart between each of the first two oil changes (5K intervals). I also have some lifter noise during startup occasionally (1 in 20 startups it's noisey). Haven't noticed excessive smoke.

ColoradoSkiCountry · January 6, 2010

i get the annoying rattle as well.

check the overflow tank on the passegers side. i had to put a piece of foam between the fender and tank to stop my 07 from rattling.

If you turned off the AFM would the oil useage stop with the guys having these issues??? Don t know? It might not help.

Don't know, but the lifters might last longer if they are not being constantly engaged/dis-engaged for AFM??? It still may pump oil up into the intake... I'm turning my AFM off as soon as I get the truck back... If it then lasts for the 5yrs or 100K I'll be happy and I'll trade it for a 6.2L non AFM.

Ron

By then I am sure the 6.2 will have AFM as well.

C. Charles Hahn · January 6, 2010

i get the annoying rattle as well.

check the overflow tank on the passegers side. i had to put a piece of foam between the fender and tank to stop my 07 from rattling.

If you turned off the AFM would the oil useage stop with the guys having these issues??? Don t know? It might not help.

Don't know, but the lifters might last longer if they are not being constantly engaged/dis-engaged for AFM??? It still may pump oil up into the intake... I'm turning my AFM off as soon as I get the truck back... If it then lasts for the 5yrs or 100K I'll be happy and I'll trade it for a 6.2L non AFM.

Ron

By then I am sure the 6.2 will have AFM as well.

Maybe, maybe not. There's rumor that a Gen-V small block will be coming out around 2012 which will use Direct Injection like most of GM's 4 and 6 cylinder engines are currently using (as are most engines from most auto manufacturers now). AFM may not be necessary by then... hell even cam-in-block may be gone at that point. There's been talk of moving to OHC or DOHC with SIDI and VVT.

2009 LTZ · January 8, 2010

08 LY5 5.3L 8700miles. No problems. I'm at 37% on my 2nd oil change of M1 T@SUV 5W-30. What role do the AFM lifters have in pooling oil in the intake manifold? They have no direct connection to getting oil into the combustion chamber.

Don't know but they do pump oil up into the intake according to GM... This is why they are called "over-active" and their is a bulletin out from GM to that effect... Yes, when you have this condition, you get plenty of oil into the combustion chambers... See picture above

rodram · January 8, 2010

By then I am sure the 6.2 will have AFM as well.

Thanks Ryan for that happy thought .... I think that if this is the case ... I will keep running my 5.7L Vortec in my gmt400.... or I will have it rebuilt as a 383 ... that will get the same displacement as a 6.2L ... and give lots of low end torque