Had 2 more trucks come in with AFM issues after I fixed the 2008 Silverado for a good customer on the cheap. A lot of things seem to come in Three's at repair shops.
1st one is another LMG 5.3L 2008 Silverado that was also missing on #4, It's getting a full AFM delete with a LQ4/LQ9 Camshaft, GM Performance "Bowtie" Lifters, 3-Bolt Cam Gear, LS2 Timing Chain, LS2 Timing Chain Damper, Melling HV-SP Oil Pump, L92 Valley Cover, ARP Exhaust manifold bolts, Along with plugging the AFM relief valve in the Oil Pan.
2nd one is a 2011 GMC Yukon Denali XL with a L9H 6.2L, Cylinder #7 Intake Lifter deactivates soon as the engine is started....But seems to be locked in the activated position when barring the engine by hand, In fact the Rocker actuates well 'til it get's oil pressure.
This is just another failure mode to add to the collection of AFM Lifter failure modes......
The Lifter has a internal oil leak between the "Lash" chamber that's fed oil at all times & the "Deactivation" chamber that's only suppose to get oil pressure when the cylinder is deactivated.
I tried to sell a full AFM delete using a L92 Camshaft, But the customer has cash flow issues, This one is getting the Lifters replaced on Bank 1 only with low mileage used ones I have laying around. Tried to sell Tuning the AFM out at cost but they wouldn't even go for that.
Unfortunately....This one is going to have a Workmanship ONLY warranty as I can't stand behind used parts.
I am going to replace the 2 outboard exhaust manifold bolts with ARP's for free just to mitigate them shearing off.
Not to be confused when BOTH Rockers on a AFM Cylinder Deactivating when not commanded to.....That's classic symptoms of a VLOM Control Solenoid stuck open.
Pic of the 2008 LMG torn down, Ready to pull the Camshaft....
Video of the 2011 L9H #7 AFM Intake Lifter Deactivating itself......
1st one is another LMG 5.3L 2008 Silverado that was also missing on #4, It's getting a full AFM delete with a LQ4/LQ9 Camshaft, GM Performance "Bowtie" Lifters, 3-Bolt Cam Gear, LS2 Timing Chain, LS2 Timing Chain Damper, Melling HV-SP Oil Pump, L92 Valley Cover, ARP Exhaust manifold bolts, Along with plugging the AFM relief valve in the Oil Pan.
2nd one is a 2011 GMC Yukon Denali XL with a L9H 6.2L, Cylinder #7 Intake Lifter deactivates soon as the engine is started....But seems to be locked in the activated position when barring the engine by hand, In fact the Rocker actuates well 'til it get's oil pressure.
This is just another failure mode to add to the collection of AFM Lifter failure modes......
The Lifter has a internal oil leak between the "Lash" chamber that's fed oil at all times & the "Deactivation" chamber that's only suppose to get oil pressure when the cylinder is deactivated.
I tried to sell a full AFM delete using a L92 Camshaft, But the customer has cash flow issues, This one is getting the Lifters replaced on Bank 1 only with low mileage used ones I have laying around. Tried to sell Tuning the AFM out at cost but they wouldn't even go for that.
Unfortunately....This one is going to have a Workmanship ONLY warranty as I can't stand behind used parts.
I am going to replace the 2 outboard exhaust manifold bolts with ARP's for free just to mitigate them shearing off.
Not to be confused when BOTH Rockers on a AFM Cylinder Deactivating when not commanded to.....That's classic symptoms of a VLOM Control Solenoid stuck open.
Pic of the 2008 LMG torn down, Ready to pull the Camshaft....
Video of the 2011 L9H #7 AFM Intake Lifter Deactivating itself......
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