For you LS swap guys.

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Terry Wilkerson

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Considering a LS swap for my truck. I'm only finding higher mileage doner engines. What would you say acceptable mileage for a swap.
 

Nasty-LSX

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175 200K as long as engine is clean inside
These motors can run forever as long as they were well maintained.
In houston I have been picking up engines with as low as 44000 to 77000 miles.
 

Drauka99

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mine was an 03 with 135k. Oil pan was clean when I changed out to a lower profile one. I wouldn't be to concerned with sub 250k if it appeared well maintained. I limited mine to 03-06 motors because i wanted , no EGR and no DOD.
 

TotalyHucked

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Mileage isn't much of a worry sub-250k. A big plus if you can hear it run first. When I bought mine, I bought it from a guy we do business with that I trust. It came out of a running/driving/rearended Envoy Denali at 104k miles. He showed me a video of him driving it around. I paid more for it, but it was worth every penny.

Or on the flip side, if you have the budget/time/means, buy the cheapest one you can and do a complete build on it. That's what I plan to do eventually, buy the cheapest aluminum 6.0 or 6.2 that's not windowed and do a stroker/HCI setup
 

Camar068

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Considering a LS swap for my truck. I'm only finding higher mileage doner engines. What would you say acceptable mileage for a swap.
less than 150k for me for anything w/o AFM.

If it's got the AFM (DOD), think twice about it. The AFM stuff can mess up ANY TIME. The seller doesn't know the history, you don't, and sh|t happens. If I were to buy an AFM with higher miles (for me over 80k), I'd plan on ditching the AFM with hardware (not the software plug-in) which is about $1k.

That 80k statement is based on what I've read, and how much it is to rebuild an LS top to bottom. I'd rather pay $1k up front vs risking paying $3.5k later.

Please someone whose actually done the AFM delete respond. My statements are based only on web research.
 
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Camar068

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less than 150k for me for anything w/o AFM.

If it's got the AFM (DOD), think twice about it. The AFM stuff can mess up ANY TIME. The seller doesn't know the history, you don't, and sh|t happens. If I were to buy an AFM with higher miles (for me over 80k), I'd plan on ditching the AFM with hardware (not the software plug-in) which is about $1k.

That 80k statement is based on what I've read, and how much it is to rebuild an LS top to bottom. I'd rather pay $1k up front vs risking paying $3.5k later.

Please someone whose actually done the AFM delete respond. My statements are based only on web research.
This is based on a good running '06 motor with ~120k miles on it that lasted a few years with only a few gasket changes on install.

Then a (prepull) $600 '04 (purchased last year) that lasted less than 10 months. The '04 was "sold" as an '06 with 145k....computer said it was an '04 4.8....no returns. Computer from another motor or visa versa? Who know's.

Like someone said, best to see it in the vehicle running and help pull it.

If/when you do it, change oil pump and the water pump....not ebay sh@rt stuff either...name brand.
 
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sickchev

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Here is my view and how I handle my 5.3 swaps. I purchased a 5.3 lm7 2001 from a awesome guy that pulls from a yard. He has them on a stand and you can hear then run. This did at least make me feel better that it would run so I pulled the trigger. It's was a 200k+ motor but I went into the purchase knowing I wanted to break it down to at least the short block. This gave me the opportunity to replace the usual suspects. Oil pump, timing set, pickup tube, valve train, and of course a choppy cam. I did go with a high volume, standard pressure oil pump because I did not change the bearings on the bottom end stock rotating assembly. This cost quite a bit of money to basically refresh and improve some on the hp.
If your goal is not crack the engine open and just stab it in the truck. Spend more money up front and find a lower milage engine that you can hear run.
 

1lejohn

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It's an LS it's good for a million miles! :favorites13: Until it's not.
 

TotalyHucked

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less than 150k for me for anything w/o AFM.

If it's got the AFM (DOD), think twice about it. The AFM stuff can mess up ANY TIME. The seller doesn't know the history, you don't, and sh|t happens. If I were to buy an AFM with higher miles (for me over 80k), I'd plan on ditching the AFM with hardware (not the software plug-in) which is about $1k.

That 80k statement is based on what I've read, and how much it is to rebuild an LS top to bottom. I'd rather pay $1k up front vs risking paying $3.5k later.

Please someone whose actually done the AFM delete respond. My statements are based only on web research.
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
 

Terry Wilkerson

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I know what DOD is but not AFM.
 

Terry Wilkerson

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Looked AFM up Active fuel management.
 

Hunter79764

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If you want a stock-ish swap, don't hesitate for anything less than 200k, think about it for 250k, and condition matters for 300k. I had a 5.3 in my wife's old suburban with 300k that I pulled out, it was still pristine (except ticking lifters) but had been taken care of. If you don't know the history, stick to 200 and below and you should be fine with basic pulling the valve cover and looking for absolute garbage and other basic info. I did get one with 160k that I didn't look close enough at. If I had, and saw the goopy RTV on the water pump, green coolant, sludge under the valve cover, and a few other signs, I wouldn't have bout it. But for $150, I was already there and he had it ready to set in the bed of the truck, so I grabbed it. My mistake.

If you want to build it up, it depends on what you want. DOD/AFM has crappy failure prone lifters, as mentioned, but if you are going to do a cam swap, it isn't much more to delete it all. I did it in my wife's current Yukon Denali, I think I spent $1300 and gained a fair amount of power. VVT, same thing, not a big deal if you want to swap cams anyway. If you want stock cam, then avoid anything with 3 letters (DOD, AFM, VVT, EPA, FBI, IRS, Etc).

Sloppy Mechanics always preferred the 300k+ engines for turbo builds because the worn rings gives you a little extra cushion, and if you blow it apart with 28 pounds of boost, you don't feel too bad grabbing another short block with 300k and stabbing it in.

If you want a nice driver for your kid and plan on putting 40,000 miles a year on it, yeah, grab yourself a lower mile unit, maybe 100-150k, and make sure it has good oil pressure.

As for accessories, I seem to get around 100k-150k on a water pump and 150-200k on alternators, both are easy swaps and stock parts seem to last longer than even AC Delco replacements. Haven't had a problem with a PS pump failing, although hydroboost hoses will probably need to be replaced. Also transmissions, 200k on a 4L60 and plan on it being toast soon, figure a rebuild. If it has a "fresh" transmission, I'd still consider it garbage unless you know who built it and how. 4L80 should be fine unless you know it has issues, or it was 300k on a cab and chassis or something severe duty like that. But every average half ton and/or suburban is going to have the 4L60, not terrible, but know the limits.
 

Bextreme04

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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
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/Activ...erly 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.
 

Ole Buck

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find you a 2003 Yukon with a L59 flex fuel. An absolute simple swap. No dod/afm crap, just set it and forget it.
 

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