Whats up guys, I have a question and I cant seem to find an answer. I drive a 2008 silverado with the infamous afm lc9 5.3. The engine seems to be f***** burnin oil, misfiring, fouling plugs and what not. I want to replace the engine. Question is my year model does not have vvt, it was introduced in 2010, does that mean I cant swap a 2010 engine even if its also an lc9 as mines. What if i swap out the ecm as well? Is the harness the same? What are the differences? Thank you for reading.
Josh Marxen: If the swap motor has a vvt and yours does not or visa versa the computer programs do not match. In some of the older cars like Chevy Ford Toyota, it was possible to just swap the ECM so it matched the swap motor. On BMW or Lexus type cars you couldnt because the car would not recognize the new ECM and the security would lock you out. The same is true on the 2010 era cars/trucks (give or take a couple years depending on make model) The computer has to match the motor and the body now. I dont know enough of the specifics to really instruct on how to do the swap, but from what I understand your computer could be reflashed to run another motor but the cost can run into the thousands so I have yet to find anyone whos bothered, its cheaper and easier to get a replacement crate motor for what you already have in the truck or upgrade to the 2010 which Chevy used the same block but changed the way it controlled it.
Luis Godinez: Okay thanks for clearing things upfor me, thingis that I have found ab abundance oflow mileage engines for the same year for sale but Im afraid that they may suffer from the same problems and a brand new crate engine is pricy what is your opinion?
Josh Marxen: With proper oil changes and tune ups these motors will run forever, but gas quality has gone down, oil changes can be expensive and sludge buildup kills them because the motors are built a lot tighter and have more internal parts like VVT than they did…See more
Luis Godinez: What exactly is a crate engine? Is it a remanufactured engine? Or a brand new engine off of Chevy? I am thinking its a remanufactured one right? and if so what is a good place to order from I live in Las Vegas if it matters.
Luis Godinez: What is a good price to pay for the swap? Unfortunately I cannot perform a swap myself I am not that knowledgeable.
Brandon Swanstrom: A crate engine can be a shortâ€‹ block, a long block, fully dressed, stock,built, remanufactured, or built match grade depends on how much $$$$ you want to spend you can put a vvt afm in place of a none vvt afm if you change the harness and control modules and access to a tech 2 BUT its not worth it afm vvt engines are more problematic lol
Luis Godinez: Okay well the reasons Im asking all these questions is because Im trying to see which route to take, so far Ive seen some used but with warranty engines from reputable sites for a little under 3k they are plug and play plus Ill have to pay for install. Does this seem like something you guys would do??
Luis Godinez: And what I mean by what is a crate engine is does it have to be new or can it be a used bit withh documents and warranty?
Brandon Swanstrom: Id be curious to see whats actually wrong with the engine Ive seen crazy cheap issues caus big problems like pcv valves though this engine isnt equipped with a valve its has more of a baffle but it can still cause oil consumption issues if the system isnt operating properly
Luis Godinez: Ive replaced the left side valve cover, replaced spark plugs, theu keep on fouling, and it burns around a quart every two weeks or so depending on driving.
Luis Godinez: Theres a tsb out for these trucks of the same year they suggest replace left side valve cover to clean the pistons and if that doesnt help to replace pistons lol
Luis Godinez: I meant replace valve cover and then replace piston rings*
Brandon Swanstrom: Right, i know all about it. But have you done a relative compression test?, a compression test?, a leak down test?
Luis Godinez: What is the point of a compression test? Is it to see if the rings indeed are roasted??
Brandon Swanstrom: I compression test will show which cylinders may be low on compression. These are the cylinders you want to then do a leak down test on this will show you where the compression is being lost. Just hate to see you through a engine at it for no reason. For example if its not the rings and you get a short block move your heads over and the valve seals or bad could have the same problem
Luis Godinez: Cool cool so a leak down test will lmk if its either the heads, valves, etc? I guess imma have to see a mechanic soon maybe im being pessamistic.
Luis Godinez: Autozone has the tools right?
Brandon Swanstrom: I dont know, they might. I dont ever go there i have a dedicated parts supplier and own all the tools
Josh Marxen: You can get basic stuff like a compression tester through auto parts stores or even Harbor Freight. Its not engine builder quality stuff but will give you a reasonable idea if your motor has dead cylinders or major internal damage. Summit is the guide I use for things like crate motors as the guys on their help line know what they are talking about and they stand behind what they sell, but ya dont just assume your engine is junk. Most mechanics will replace it if you insist on it and its cheaper to replace with a reman motor than it is to rebuild what you have now, but even I have a guys I go to for options because if I had enough money for all the specialized tools out there I could retire.
Luis Godinez: I just watched a video on how to perform a leak down test, doesnt seem like rocket science. the only thing I dont have is a compressor but I might just purchase one.
Luis Godinez: And I really wish it was something else but the amount of oil my engine is consuming is crazy plus that tsb basically addressing my exact problem leads me to believe its the rings.
Josh Marxen: I think I gave about $20 for the last compression tester I bought. Put a lot of time and money into my wifes trailblazer because of a miss that turned out to be 2 dead cylinders that I was sure was an electrical issue. My buddy who owns his own shop w…See more
Luis Godinez: thats a bummer and it doesnt blow any smoke at all but I guess that doesnt mean that its not burning it, it does not leak a single drop till now.
Luis Godinez: I guess ill be performing the compression test my self later this week.
Luis Godinez: When does an engine rebuild outweight getting a new engine??
Josh Marxen: When you have to replace the heads. These new aluminum heads are more prone to warping and cracking and on a V8 can cost $2000 up just to replace them and your timing stuff (recommended as long as your in there anyway) For around $3500 you should be ab…See more
Luis Godinez: I see I see so basically itd be better to drop in a replacement and also be cautious about where I get my engine from. I basically see two options here buy a used engine for around 25 hundred or a remanned long block for around 35 hundred give or take on both, ive seen some place charge 2500 extra before sending the core back though â˜¹ï¸
Josh Marxen: Its always possible yours could be fixed for $1500, but unlike the 50s 60s and 70s cars a hone job and new rings and bearings is a 1 in 10 chance rather than 9-10. They started making disposable 100k motors in the 80s and the quality wars started …See more
Luis Godinez: Yes Im inclining towards getting a new engine or atleast low mileage used, Im not sure which one to get though I just had a shop quote me 4800 for a remanned engine including labor which doesnt seem so bad and 4200 for a used engine with 99k including labor. The used engine with 6 months warranty and the new one with 3 years unlimited mileage.
Luis Godinez: How do you clean the pistons and cylinders by removing the spark plug??
Josh Marxen: That sounds about right and why I recommend the reman for the little extra. They are figuring $4200 even on the used because any good shop will put at least a new gasket kit, water pump thermostat type work into a used but its still unknown how it was…See more
Luis Godinez: Imma pour some top end cleaner into the cylinders through the spark plug hole of course being careful not to put too much and removing it before igniting the engine. Just as a last ditch effort.
Josh Marxen: Some cleaner in the tank or oil wouldnt hurt either. I once drained the oil on a 77 LTD filled the crankcase with diesel and let it idle for 5 min. (It was a car for a demo derby) but it looked like liquid coal when I drained it. Car would hardly pull itself before, ran great after. They also have scopes that hook to a smartphone now so you can see inside without tearing it apart
Luis Godinez: Ive already tried some seafoam in the tank as well as in the crankcase it made zero difference, like you said Im positive the engine is fucked but Ima try the engine cleaner in the cylinders, is there anything you suggest?? What else might be causing …See more
Josh Marxen: It could be running down a bad valve guide. If the engine is sludged up the oil wont run down quick enough and the pressure can push it down the valves. But a crack can do the same. If your finding one or 2 blackened plugs that is a sure sign of inter…See more
Luis Godinez: My cylinder 7 plug has fouled up twice in one year and is also at 70% compression
Luis Godinez: The mechanic said it appears valve seals are bad and rings are also bad
Luis Godinez: Is 1800$ too much for labor?
Josh Marxen: Not as long as that covers any machine shop time. Otherwise it could run another several hundred on top of that and then your in reman with warranty money range. I think Napa has a book time hours guide for a lot of popular repairs. Hourly rate varies…See more