2012 Yukon XL - 6.2L Engine Rebuild/Swap & Addressing AFM/DOD

[smiley91]

Apologies in advance for yet another AFM/DOD post to muddy the forum waters, but I have the 6.2L with 180k. It has a collapsed lifter and low oil pressure (leaking from oil pump). It may be conjecture for me to assume that it is AFM related, but I do hear that this type of problem is a common symptom of how the AFM functions. It looks like my best option is to put a remanufactured engine in it. I could try the rebuilding route, but there is no guarantee that there aren't other internal issues happening on outside of lifters and oil pump, so I don't want it to end up being a money sink when just swapping could be less headache (but I am open to ideas if you all disagree with this mentality). I have called a couple of places, getting a feel for how they do the swap, and I brought up the AFM point. Multiple places are recommending just to swap it with a crate 6.2L engine from GM directly that will come with a 3-year/100k warranty.

Challenge is, if I have them put a delete kit on it, it will likely void the warranty from GM. If this is a reused block with all new internal components (lifters, rockers, cam, rods, etc), would just tuning out the AFM be good enough in this instance? I know that the parts will still be for AFM, but is it worth the extra cost at this point to mechanically delete it?

 

[Dustin Jackson]

@smiley91 With 180k I think you're well past any GM warranty out there.

If you can get the motor properly diagnosed then rebuilding it has little to no risks, it's when people make assumptions and apply a "fix" to the problem without actually identifying the problem.

There should be shops out there that have experience with this type of things, any shop that jumps straight to replacing the motor isn't interested in properly fixing the problem.

 

[swathdiver]

Apologies in advance for yet another AFM/DOD post to muddy the forum waters, but I have the 6.2L with 180k. It has a collapsed lifter and low oil pressure (leaking from oil pump). It may be conjecture for me to assume that it is AFM related, but I do hear that this type of problem is a common symptom of how the AFM functions. It looks like my best option is to put a remanufactured engine in it. I could try the rebuilding route, but there is no guarantee that there aren't other internal issues happening on outside of lifters and oil pump, so I don't want it to end up being a money sink when just swapping could be less headache (but I am open to ideas if you all disagree with this mentality). I have called a couple of places, getting a feel for how they do the swap, and I brought up the AFM point. Multiple places are recommending just to swap it with a crate 6.2L engine from GM directly that will come with a 3-year/100k warranty.

Challenge is, if I have them put a delete kit on it, it will likely void the warranty from GM. If this is a reused block with all new internal components (lifters, rockers, cam, rods, etc), would just tuning out the AFM be good enough in this instance? I know that the parts will still be for AFM, but is it worth the extra cost at this point to mechanically delete it?

Any GM dealership will not delete AFM or even disable it. Not allowed to.

I'm curious about where the oil pump is leaking from, don't hear about that much.

It's in most shop's best interests to just swap out one engine for another, saves them time and most don't have the expertise for rebuilding anyways. A performance shop does.

When an engine is disassembled for rebuilding, the block and heads go through testing to make sure that they are serviceable and without cracks in them. Then measurements are taken of the cylinder, camshaft journals, connecting rods, crankshafts to see if any can be used again and if any minor machining is required along with what size bearings will be used during the rebuild.

You basically want to convert your L94 into an L9H or convert a crate LS3 into an L9H. Have you actually seen any GM 6.2 crate engines recently? They've been eluding me!

 

[Geotrash]

I have a 2012 XL Denali as well and did a cam swap including oil pump in my garage. Got some bad lifter trays from an aftermarket vendor and ended up doing the job 3x until I figured it out. But now it’ll outrun pert near anything else’s in its weight class.

Are you handy, have some tools and comfortable working on this truck? If so, we’ll get you through the job and you’ll spend about $1500 in parts. If not, a Jasper L9H will run you $8K installed but is basically an L94 without AFM.

180K is nothing on the bottom end on these if they’ve been maintained well and run on premium fuel. If I were in your shoes, I’d tear into that thing and put a new cam, lifters, pushrods and oil pump in it. It’ll take you 1-2 weekends and it’ll feel good when you’re done.

 

[Wander]

I have a 2012 XL Denali as well and did a cam swap including oil pump in my garage. Got some bad lifter trays from an aftermarket vendor and ended up doing the job 3x until I figured it out. But now it’ll outrun pert near anything else’s in its weight class.

Are you handy, have some tools and comfortable working on this truck? If so, we’ll get you through the job and you’ll spend about $1500 in parts. If not, a Jasper L9H will run you $8K installed but is basically an L94 without AFM.

180K is nothing on the bottom end on these if they’ve been maintained well and run on premium fuel. If I were in your shoes, I’d tear into that thing and put a new cam, lifters, pushrods and oil pump in it. It’ll take you 1-2 weekends and it’ll feel good when you’re done.

I have just run into the lifter failure problem on a "new to us" 2012 Yukon XL Denali. It's at 170k and calling a couple places puts the repair bill out of range for us. And I've been watching some videos and it looks like something I can do. Now I'm trying to figure out the right kit/parts.

This is my wife's daily driver and we pull a trailer a few times a year but other than that I'm not worried about increasing performance, getting it running again and reliability is the focus.

There is one from AMS racing that looked about right, but I'm not far enough in to know what the lifter options mean. Is there a canned kit I can get that has everything I would need?

 

[Geotrash]

I have just run into the lifter failure problem on a "new to us" 2012 Yukon XL Denali. It's at 170k and calling a couple places puts the repair bill out of range for us. And I've been watching some videos and it looks like something I can do. Now I'm trying to figure out the right kit/parts.

This is my wife's daily driver and we pull a trailer a few times a year but other than that I'm not worried about increasing performance, getting it running again and reliability is the focus.

There is one from AMS racing that looked about right, but I'm not far enough in to know what the lifter options mean. Is there a canned kit I can get that has everything I would need?

Texas speed and performance sells pre-packaged DoD delete kits that include much of what you need. But, you can also get a factory cam from the L92 or L9H - both are Gen IV 6.2L without AFM but they retain VVT. The L9H cam plus Chevrolet Performance LS7 lifters and GM lifter trays would make a great core of an inexpensive cam swap project and you can keep all of the stock rockers and springs. Here is a complete parts list for you if you want to roll your own:

• Cam: GM 12711967. Factory cam for the L9H (6.2L non-AFM). $295.
• Cam magnet: GM 12653140, $36
• VVT solenoid/actuator, GM 12682000, $84
• Lifters: Chevrolet Performance 12499225 Hydraulic Roller Lifters, $463
• Lifter trays (use only genuine GM for these), GM 12595365, $10x4
• Pushrods: GM OEM, $15 (buy just one or two in case you have one or two that are bent)
• Flat valley pan and gasket, GM 12598832, $67
• Oil pump, Melling M365HV, $171
• Cylinder head gaskets, Fel-Pro FEL-26192PT, $47x2
• Cylinder head bolts, ARP, ARP-134-3610, $118
• Intake manifold gasket set, Fel-pro MS97126, $30
• Valve cover gaskets, GM Genuine, $18x2
• Oil pressure sensor, Delco 12673134, $38
• Steel exhaust manifold gaskets, Mahle MS16124, $12
• Exhaust manifold bolts, ARP 134-1202, $38
• Water pump, Delco 252901, $132
• Thermostat, GM Genuine, $33
• Camshaft Thrust Plate, FEL-PRO ES73115, $28
• Oil cooler gasket: Mahle B31872, $8, same as the OEM design. I tried the Fel-Pro version first and had problems getting it to seal fully. Use the Mahle or OEM.
• Harmonic balancer bolt: ARP 2342503, $40. It's reusable! Use the ARP ultra-torque lube and torque it sufficiently with an impact wrench and not have to mess around with the whole torque-to-yield BS of the factory design.

Special tools to have on hand before you start:

• Harmonic balancer installer tool for LS engines: https://www.amazon.com/gp/product/B07F1F659D/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
• Harmonic balancer puller kit: https://www.amazon.com/gp/product/B01AIRR4EY/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
• Power steering pulley tool: https://www.amazon.com/OEMTOOLS-270...eering+pulley+tool&qid=1611851273&s=hi&sr=1-3
• Timing cover seal alignment tool: https://www.amazon.com/gp/product/B08CSMWKGL/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
• Hose clamp tool: https://www.amazon.com/Flexible-Clamp-Pliers-Locking-Water/dp/B07C3LYZM7/ref=sr_1_6?crid=3J4Y5OXFDL6EK&dchild=1&keywords=hose+clamp+tool&qid=1611851361&s=hi&sprefix=hose+clamp,tools,172&sr=1-6
• Your truck has a stretch belt for the A/C belt, so this tool will be needed: https://www.amazon.com/Drake-Off-Ro...+belt+tool&qid=1611852388&s=automotive&sr=1-2
• Comp Cams assembly lube: https://www.amazon.com/Competition-...embly+lube&qid=1611852151&s=automotive&sr=1-2
• It's really helpful to have both 6 and 12 point sockets on hand.
• I needed 1/4", 3/8" and 1/2" drive torque wrenches for the complete range of torques.
• A good quality, low profile impact wrench makes short work of getting that Jesus bolt off the crankshaft. This is the one I have: https://www.harborfreight.com/12-in-composite-xtreme-torque-air-impact-wrench-62891.html
• 12-point 27mm socket for the ARP harmonic balancer bolt.

Hope this is helpful. Let us know if you decide to tackle the project and good luck! Here are my notes from when I did mine:

2012 Yukon XL Denali 6.2L Cam Swap Thread

I love that Cam Motion measures each cam after grinding and finishing. Here's the cam card. Blub blub blub...

www.tahoeyukonforum.com

 

[Wander]

Texas speed and performance sells pre-packaged DoD delete kits that include much of what you need. But, you can also get a factory cam from the L92 or L9H - both are Gen IV 6.2L without AFM but they retain VVT. The L9H cam plus Chevrolet Performance LS7 lifters and GM lifter trays would make a great core of an inexpensive cam swap project and you can keep all of the stock rockers and springs. Here is a complete parts list for you if you want to roll your own:

• Cam: GM 12711967. Factory cam for the L9H (6.2L non-AFM). $295.
• Cam magnet: GM 12653140, $36
• VVT solenoid/actuator, GM 12682000, $84
• Lifters: Chevrolet Performance 12499225 Hydraulic Roller Lifters, $463
• Lifter trays (use only genuine GM for these), GM 12595365, $10x4
• Pushrods: GM OEM, $15 (buy just one or two in case you have one or two that are bent)
• Flat valley pan and gasket, GM 12598832, $67
• Oil pump, Melling M365HV, $171
• Cylinder head gaskets, Fel-Pro FEL-26192PT, $47x2
• Cylinder head bolts, ARP, ARP-134-3610, $118
• Intake manifold gasket set, Fel-pro MS97126, $30
• Valve cover gaskets, GM Genuine, $18x2
• Oil pressure sensor, Delco 12673134, $38
• Steel exhaust manifold gaskets, Mahle MS16124, $12
• Exhaust manifold bolts, ARP 134-1202, $38
• Water pump, Delco 252901, $132
• Thermostat, GM Genuine, $33
• Camshaft Thrust Plate, FEL-PRO ES73115, $28
• Oil cooler gasket: Mahle B31872, $8, same as the OEM design. I tried the Fel-Pro version first and had problems getting it to seal fully. Use the Mahle or OEM.
• Harmonic balancer bolt: ARP 2342503, $40. It's reusable! Use the ARP ultra-torque lube and torque it sufficiently with an impact wrench and not have to mess around with the whole torque-to-yield BS of the factory design.

Special tools to have on hand before you start:

• Harmonic balancer installer tool for LS engines: https://www.amazon.com/gp/product/B07F1F659D/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
• Harmonic balancer puller kit: https://www.amazon.com/gp/product/B01AIRR4EY/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
• Power steering pulley tool: https://www.amazon.com/OEMTOOLS-270...eering+pulley+tool&qid=1611851273&s=hi&sr=1-3
• Timing cover seal alignment tool: https://www.amazon.com/gp/product/B08CSMWKGL/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
• Hose clamp tool: https://www.amazon.com/Flexible-Clamp-Pliers-Locking-Water/dp/B07C3LYZM7/ref=sr_1_6?crid=3J4Y5OXFDL6EK&dchild=1&keywords=hose+clamp+tool&qid=1611851361&s=hi&sprefix=hose+clamp,tools,172&sr=1-6
• Your truck has a stretch belt for the A/C belt, so this tool will be needed: https://www.amazon.com/Drake-Off-Ro...+belt+tool&qid=1611852388&s=automotive&sr=1-2
• Comp Cams assembly lube: https://www.amazon.com/Competition-...embly+lube&qid=1611852151&s=automotive&sr=1-2
• It's really helpful to have both 6 and 12 point sockets on hand.
• I needed 1/4", 3/8" and 1/2" drive torque wrenches for the complete range of torques.
• A good quality, low profile impact wrench makes short work of getting that Jesus bolt off the crankshaft. This is the one I have: https://www.harborfreight.com/12-in-composite-xtreme-torque-air-impact-wrench-62891.html
• 12-point 27mm socket for the ARP harmonic balancer bolt.

Hope this is helpful. Let us know if you decide to tackle the project and good luck! Here are my notes from when I did mine:

2012 Yukon XL Denali 6.2L Cam Swap Thread

I love that Cam Motion measures each cam after grinding and finishing. Here's the cam card. Blub blub blub...

www.tahoeyukonforum.com

Thank you, this is perfect! I'll look through everything and start ordering soon.

 

[rdezs]

Pay attention to which camshaft they package when looking for the AFM DOD delete for the 6.2 on their website. It will likely only offer you the lower lift camshaft that came on the 6.0. You will obviously lose some horsepower on that. The correct camshaft is from the l9h engine as detailed in the list above in the previous post. That is assuming you want to keep it basically stock and just not have the AFM DOD and retain the variable valve timing.

 

[petethepug]

Door #3 is slapping in an L96 6.0L 360/380 hp/tq from a 3/4 or 1T truck. No DOD/AFM, e85, iron block, aluminum heads runs on Reg gas and turn key install. You’ll just need a tune to turn off the AFM in your existing ECM. Do a cam swap if you want the full 400hp back of the 6.2L.

L96 6.0L Engine Upgrade Guide: Expert Advice for L96 Mods to Maximize Performance

[Editor’s Note: This L96 engine upgrade guide is part of a series of LS engine upgrade guides assembled by a team of LS experts at Summit Racing that we are sharing at …

www.onallcylinders.com

I finally got this done a couple weeks ago. Thanks to everyone here for your input, especially Swathdiver. Your assessment was spot on. This was plug and play with the tune, runs great on regular gas. I think we're going to go back into the tune a little, we just used the stock L96 parameters. Gas mileage is down about 2 MPG, but O2 sensor and fuel trim data look perfect on my Snap on scan tool. I'm thinking that the premium fuel L94 with more aggressive timing may just be a bit more efficient. Anyway, I'm very pleased with the results and the increased bottom end torque is noticeable.

 

[Fernando Escobar]

Pay attention to which camshaft they package when looking for the AFM DOD delete for the 6.2 on their website. It will likely only offer you the lower lift camshaft that came on the 6.0. You will obviously lose some horsepower on that. The correct camshaft is from the l9h engine as detailed in the list above in the previous post. That is assuming you want to keep it basically stock and just not have the AFM DOD and retain the variable valve timing.

when I was checking this site last the packages offered the cam that's identical to an LS7 cam. When I posted about it many asked if I was turbo charging my engine, which I was not. If you don't care for a special cam Check rock auto for an L92 cam or an L9H cam and buy it separately. just did this and started the dismantling of my engine.