For you LS swap guys.

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TotalyHucked

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DOD and AFM are the same thing. DOD is what GM called it before the 2000's. It is now AFM(trademarked by GM), but everyone just calls it AFM/DOD. Late Gen III started to get DOD/AFM and then Gen IV got AFM and VVT in various mixes.
https://en.wikipedia.org/wiki/Active_Fuel_Management#:~:text=Active Fuel Management (formerly known,conditions to improve fuel economy.

I got an L9H for my 2011 Suburban for $1500 with ~150k on it. It is a non-AFM, VVT, all aluminum Flex-Fuel 6.2L. It has the casting to allow it to be DOD, but was not equipped as such from the factory. I bought about $1500 in new parts to put a TSP L92 Stage 1 VVT cam kit in it with new delphi LS7 lifters and new oil pump, bearings, piston rings and gaskets throughout. The bore was still in spec, so it got a deglazing hone and reused all of the stock internals. Heads got checked and it needed all new exhaust valve guides and new springs from the TSP kit installed. You can mechanically block off the AFM holes to prevent any oil pressure bleed by ordering a National/Timken LM603049 bearing and taking it apart. The rollers are the exact size to fit in the AFM tower holes and it only costs ~$13 or less for the whole bearing.
https://www.summitracing.com/parts/...4HXwB2OGKb3C093eSmeE3g73kC6yivyhoCh1wQAvD_BwE

For simplicity you can stay with the older iron block engines and run a 5.3/60 with up to 200k miles with no issues. Best if you can find a 6.0/4l80 combo and just do a quick cleanup and replace any leaking gaskets like front/rear mains and oil pan gasket while out of the vehicle. Put a decent mild cam in it like a truck norris and you'll probably have many years of trouble free driving with the mileage most of us are putting on our trucks. Our 2011 Suburban is my wifes daily driver and our vacation trailer tow vehicle. It is sitting at 230k miles right now and still going strong. I've only ever had to replace motor mounts, spark plugs, and one exhaust manifold bolt on the engine in the 6 years and ~100k miles I've owned it. It has needed to have the transmission and differentials rebuilt in that time... but the engine has been rock solid.
Yep, you're right. Got the brain fog today. Mine was DOD and I was expecting it to be VVT but found it wasn't on teardown. Agreed with everything, no matter what engine you go with, at least tear it down to the long block and replace all gaskets/seals and check the cylinder walls. But they're near bulletproof if they've been maintained properly.

Since my motor had 104k and I knew it ran well, I didn't expect to find any surprises. I pulled it down to a long block so I could put all fresh gaskets/seals and head gaskets on it. I popped one main cap and one rod cap off to check the bearings in mine, they were perfect. Also checked the thrust of the crank (was perfect), the cylinder walls looked great, the whole bottom end turned like butter so I didn't go any further. New gaskets top to bottom, new lifter trays, LS7 lifters, chromoly pushrods, BTR stage 4 V2 truck cam (at the time), LS2 valvesprings and buttoned it back together. Ran strong for 27k miles before I tore it back down to do a rear main (the one seal I didn't replace) and bigger cam upgrade.

The one thing I will advice against is buying LS7 lifters. I bought mine pre-pandemic and they've been fine but we've seen a ton of failures since then with the LS7s, no matter whose they are. If I needed a set now, I'd run either Johnson or Morel. They pay alot more attention to metallurgy and QC than GM/Delphi do with their mass production.
 

custodian

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Agreed with everything you said. AFM/DOD can crap the bed at any time. My engine was DOD but not AFM. I was putting a cam in anyway so I didn't care, replaced all the lifters/trays/pushrods when I did the cam. I would do that with any engine I'm doing regardless cuz keeping a stock cam is not happening lol
You can have your PCM tuner turn off the DOD.
 

Terry Wilkerson

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I bought a 5.3 LS for my 1986 GMC truck. Having trouble finding long tube header for it. Prefer a reasonable priced set. Any help appreciated.
 

CalSgt

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I bought a 5.3 LS for my 1986 GMC truck. Having trouble finding long tube header for it. Prefer a reasonable priced set. Any help appreciated.
Seems like the general consensus around here has been the Holley cast steel manifolds for LS swaps. I don’t have experience with them it I’m sure someone will chime in.
 

TotalyHucked

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I bought a 5.3 LS for my 1986 GMC truck. Having trouble finding long tube header for it. Prefer a reasonable priced set. Any help appreciated.
The Holly manifolds @CalSgt mentioned are a great option. Another one (that I went with) are the Speed Engineering longtube headers. The 1 3/4” are what I run, been on for 36k miles and 4 years now. They’re awesome for a budget header. Nice thick flanges. I used the factory MLS gaskets. Also, if you go that route buy they’re plug wires as well, they fit better than any others. You will have a couple that touch or are close to touching, so also get some spark plug bolts. I’ve had one touching the whole time, touching hard, and it’s never had a problem. Just made a mark on the boot, that’s all
 

Terry Wilkerson

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The Holly manifolds @CalSgt mentioned are a great option. Another one (that I went with) are the Speed Engineering longtube headers. The 1 3/4” are what I run, been on for 36k miles and 4 years now. They’re awesome for a budget header. Nice thick flanges. I used the factory MLS gaskets. Also, if you go that route buy they’re plug wires as well, they fit better than any others. You will have a couple that touch or are close to touching, so also get some spark plug bolts. I’ve had one touching the whole time, touching hard, and it’s never had a problem. Just made a mark on the boot, that’s all
I check out Speed Engineering. I have a nephew who has 3 LS swaps for himself and a couple for other guys. He a fan of long tube headers and I'm going to take his advice and yours. In reality I'm going to help him swap my square. I might never get it done on my own. Here is a couple picks of his pontiac. It has 575 wheel hp. It's a 6.0 and built. Zero to 60 in 3 sec.
 

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SquareRoot

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Seems like the general consensus around here has been the Holley cast steel manifolds for LS swaps. I don’t have experience with them it I’m sure someone will chime in.
^^^^^^^. As I said before, long tube headers suck baboon balls. I absolutely love my Holley cast manifolds.
 

TotalyHucked

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^^^^^^^. As I said before, long tube headers suck baboon balls. I absolutely love my Holley cast manifolds.
Why? I've never had an issue out of longtubes other than some extra heat on the floor pan in a couple cars. I put LTs on everything
 

SquareRoot

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Why? I've never had an issue out of longtubes other than some extra heat on the floor pan in a couple cars. I put LTs on everything
Your an exception. You have an LS AND manual trans. The rest of em.....baboon balls. Pic for effect.
 

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Terry Wilkerson

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Change of plan. I bought a 2002 6L and a 4L65e out of an escalade. Kept the 997 heads off the 5.3. Traded the 5.3 block and the heads that were on the 6L to transmission rebuilder for a complete rebuild on the trans. Trans was 4x4 so tail shaft and housing change out. Long block is getting new bearings, rings, oil pump, shallow oil pan, timing set. Other related parts are starting to show up. Going with 3in. exhaust with X pipe. Sprung for Dakota Digital.
 

Camar068

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Change of plan. I bought a 2002 6L and a 4L65e out of an escalade. Kept the 997 heads off the 5.3. Traded the 5.3 block and the heads that were on the 6L to transmission rebuilder for a complete rebuild on the trans. Trans was 4x4 so tail shaft and housing change out. Long block is getting new bearings, rings, oil pump, shallow oil pan, timing set. Other related parts are starting to show up. Going with 3in. exhaust with X pipe. Sprung for Dakota Digital.
Read up on Galley Plug Dumbbell. I went ahead and replaced this engine's galley plug with aftermarket instead of stock.
 

Terry Wilkerson

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Any recommendation on a radiator with electric fans for my 6.0 ls with automatic trans and air conditioning.
 

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