Replacing 4.0

Discussion in '2005+ Ford Mustang v6 4.0L Tech' started by Jason007, Mar 15, 2023.

  1. Jason007

    Jason007 Junior Member

    I have a 2009 v6 manual and it’s not starting. I tried to start it one day and it was rattling pretty bad then it shut off, tried to start it again and I heard one click. The guy who towed it said it was internal, and it wasn’t the starter clicking. I have relatively low knowledge on engines but I have some. It doesn’t crank or turn over. The transmission is going too, the synchros are out and getting it into first and second is very difficult. Essentially I’m stumped on what to do keeping the costs low. I have always wanted a 4.6, more than a 5.0. I’m in love with this car, I bought it with 160k on it and drove it for about 2000 miles. I could tell the car was beat on.

    I would like to keep the car and repair it but I would also like to buy a 4.6. However cars right now are very expensive and I’m having trouble finding a GT with 100k or less for around 12000.

    so my options are Buy a used 4.0 engine and drop it in, rebuild the motor I have which also has timing chain issues, sell it and buy another 4.0 or upgrade to a 4.6, or just scrap the whole thing and get another car. Again, I am in love with the 05-09 mustangs so I am passionate about keeping it.

    If I buy a used engine, where should I buy one? LKQ? eBay? I would like to keep the costs low so cost friendly options are appreciated. I read somewhere that swapping it to a 4.6 isn’t worth it and I should just buy a 4.6 instead since I would need a new transmission driveshaft and rear end plus more I don’t know about. I’ve seen I can get 4.0s for pretty cheep and the transmissions are cheep too. And if I buy a used engine from a scrap yard am I able to just drop it in? Should I find a low mileage one or should I get a high mileage one and rebuild it? Thanks in advance for the answers.
    Dillon Miller likes this.
  2. Juice

    Juice forum member

    Well, for one thing, your transmission issues are due to needing a clutch. Not knowing how long that has been an issue, you may now have worn syncros in the trans.

    You really need to figure out what that "internal issue" is before you can make the right decision. I do know good used 4.0 s were hard to find 5 years ago when I did my coyote swap. Guy who bought my low milage (100k) 4.0 was telling me about it.
    If I was to do this, I would prefer a reman engine.
    Cancerman and Jason007 like this.
  3. TARA-fied1

    TARA-fied1 Member

    If you have access to a compression tester, I'd check compression. My 07 4.0 quietly broke the timing chain. Just quit running. Wouldn't start. It cranked over but did nothing to try and start/run. Anyway, I pulled it apart after checking the compression (which it had none). It bent all the valves and broke two of them. The 4.0 is an interference engine so if it jumps time it is catastrophic. I bought a wrecked 2012 car and swapped everything into my 07 because I really didn't want another 4.0 but it's not something I'd recommend if you haven't done a lot with cars.
    Jason007 likes this.
  4. Dino Dino Bambino

    Dino Dino Bambino I have a red car

    @Jason007 if your 4.0 is terminally damaged, I suggest you consider buying either a wrecked 11-14 V6 or a wrecked 11-14 GT and basically doing exactly what @TARA-fied1 and @Juice did to their cars. A Cyclone 3.7 V6 or a Coyote 5.0 V8 would be a much better platform if you're planning on long term ownership of the car, and a donor car will have all the parts you need to complete the project.
    Jason007 and TARA-fied1 like this.
  5. Juice

    Juice forum member

    FYI my engine was fine. I only needed a clutch.
    asdrew and Jason007 like this.
  6. DieHarder

    DieHarder Senior Member

    Well, you're either in for a lot of work or a lot of money (maybe both). I've rebuilt several cars over my lifetime and don't regret any of it though I made several mistakes along the way but really enjoyed the experience and learning about cars. My suggestion is buy a complete set of manuals so you know what's involved and go from there. From the sounds of what you have recommend as Juice says it would probably be best to buy a rebuilt/ remanufactured engine and used trans to replace what you have as the simplest route to get it back on the road. Either that or sell and save your money for a better car.
    Last edited: Mar 17, 2023
    Jason007 likes this.
  7. Dillon Miller

    Dillon Miller Junior Member

    As someone who has been in this situation before all be it I owned my 4.0l a little longer than you before mine took a dive. First I would recommend actually finding out what's wrong with the engine, or trans i'd rather spend 500 dollars in diag then begin a 2k plus swap that I might not of needed. You can also figure out if its the guides by pulling off your valve covers on both sides and look at the front and back timing guides check if they're broken or if there is slack in the chain. Did it jump teeth? Do a compression test and see if you bent a valve.

    Assuming the engine is toast, 4.0's at least in my area aren't that hard to come by. For reference my car was an 06 4.0l v6 automatic when my guides blew (front and back) I wanted to just get a new 4.0l give it new gaskets, seals, timing, comps, tensioners, oil pump etc, and get my car back. I did it, and it runs today. I also manual swapped it at the same time so it should be cheaper for you. In total price wise I think all in getting the engine, and rebuilding probably cost around 900 dollars, but I also had to buy an engine stand and a cherry picker( 600 together). I have a well lit garage I could work in, do you? These are all variables to take into consideration. Do you have the time for an engine swap or rebuild? My engine rebuild and tranny swap took me over 5 months, 7 to 8 if you count me getting the tools, and me actually figuring out my guides were shit.

    I'm not trying to dissuade you. I get it I love the s197 and didn't want to get rid of mine, I went through two relationships and it was always there I didn't want to abandon it. However, be realistic with your skills, toolsets you have available, the time you have, and the dedication needed to confront the task.

    Now that I got the rambling, and warnings out of the way. Some advice for if you go the 4.0l route like I did. YOU NEED TO DO THE TIMING JOB BEFORE YOU SHOVE THE ENGINE BACK IN! Get it done and out of the way and you'll have an engine that will last you another 150ks, these 4.0ls are tanks besides the plastic timing guides and plastic thermostat housing. I recommend looking around at junkyards and find the lowest mileage 4.0l, or browse by marketplace on FB that's what I did and got mine for 400 bucks. If you redo the timing(which you should do on either the old or new engine) ford loves fucking loves internal torx bits get a set if you don't have them. BUY THE FUCKING CAMSHAFT LOCKING TOOLS they're 80 bucks and keeps you from crying when the engine is off by a tooth or two when it starts again. Also change the rear main seal, will need a ford special tool for it as well.

    -This is a link to the engine timing guide I followed when I rebuilt my engine-

    -Buy this book you will thank me later-

    -camshaft locking timing tools-|tkp:BFBMwt3dg95h

    -Timing chain/guides/sprocket kit-

    -video on how to check your timing guides
    its the first link I sent its literally within the first 5 minutes
  8. Jason007

    Jason007 Junior Member

  9. dhrmx5

    dhrmx5 Junior Member

    I did a 4.6/4.0 swap and it was easy. BUT, I bought a rolled over 4.6 car and used the engine/ecu/trans/driveshaft/rear axle complete. The engine wiring plugged right into the body harness. You should be able to buy a rollover off Copart or IAA for about 2500. This only worthwhile if the chassis you have is very clean. Beater 4.6 cars are cheap
  10. cgornowich

    cgornowich forum member

    My first suggestion would be to sit down and figure our exactly what you want to do with the car BEFORE you do anything. If you like the car as it was (newish), then buy a replacement 4.0 like Dillon said above and enjoying learning about how your car is assembled.

    But, if you want to have fun, I'd vote to swap in something better. Maybe a 4.6, and buying a wrecked donor is the best way, like DHRMX5 outlined. And Dino Bambino had a good suggestion with the 3.7 or 5.0 Or you could go "hardcore" and swap in an LS.

    I started out with slightly stock Saleen Racecraft, then kept modding until the car protested and, while it's been fun, I wished I would have swapped in an LS when I threw a few rods out the side of the block.

    Bottom line, treat it like a trip, map out the route and things you want to do BEFORE you start out the door.
    Just my2 cents.
    Charlie G
    Jason007 likes this.
  11. RetDrumSgt

    RetDrumSgt Member

    Love this site. You guys knowledge and willingness to help and share is awesome. Only thing I can contribute, I agree, the 05 through 09 are great cars.
    Dillon Miller likes this.
  12. Dillon Miller

    Dillon Miller Junior Member

    Sorry for seeing this late, I come by the forms mainly to lurk. So in regards to your first question having someone else do it is going to be an expense that I can't give with to much certainty. As for engines If you are having a hard time finding engines for cheap just spend the cash on yours, that is only if yours is safe to do so as long as it did not jump time, or overheat you are good to rebuild the engine and it will last you a while yet (another 150ks conservatively). this will probably cost you the same as buying a used engine, but the thing with getting it rebuilt is your timing guides are good, you do not know the condition of the mystery engine you buy off of ebay. Even if you do go the route of buying a new engine you need to change the guides on it otherwise you'll be in the same position as you are now 1 year in the future if you buy an engine with around 160ks. You might get away with it on lower mile engines. I think both prices would be about the same buying a used engine and having them put it in might be more purely from a parts perspective id guess 3k total if you went that route. 2k and probably lower to rebuild your engine and get it running again. Realistically the price is probably comparable either way when you factor in shipping and other little fees that come with buying engines online.

    if you only see 4.0 engines going for 1600 that have 160ks don't pull the trigger, at around 160ks the 4.0ls timing guides start to commit suicide. For 1600 you only want to buy engines with around 100ks or less if they have any more miles than that the sellers are snorting crack(respectfully)

    Another engine tip, when looking for them the engine is the same from the ford explorers if you find one with low miles, you can swap it in your car if you swap the intake manifolds out for the one on your car most engine prices are based on the cars they are from not the actual engine so you could get it for a steal, id take a look around.

    SO TLDR for this first half just rebuild your motor, under two conditions : First if it jumped time don't bother, these 4.0ls are interference engines its a problem, Second if its ever overheated the heads can warp because their aluminum and the block is cast iron if this happens the heads won't sit flat on the engine and you'll have a head gasket leak perpetually.

    If you cant rebuild your engine, and don't want to buy another 4.0, or cant find one for a reasonable price , 4.6l swap it

    First buy a clapped v8 donor of the same year(this is important mainly for wiring differences) some other people mentioned this and I think it's valid (I considered it but pricing in my area wasn't good for my budget) just have the mechanics take whats in your car out and plant in the engine and trans, diff, drive shaft, and ECU from the v8 in. Labor is going to kill you in cost, but you will have a GT congrats. Someone else mentioned you could get a flipped over GT for sub 2k and I think that's fair for the money. In total I would say your price point for the donor car plus labor is going to be 4 to 5k. It really depends on who you have working on it. If it's your buddy probably less.
    Last edited: Mar 24, 2023
  13. Dillon Miller

    Dillon Miller Junior Member

    As for transmissions the 4.0ls came equipped with the old school t5s and are relatively cheap all things considered for example you can buy a brand new one for 2k, I got mine for 400 dollars and it had 80ks on it. Try to find the transmission below or at 100ks and realistically it should be around a 1000 dollars. Ford put the 4.0l and t5 in almost every car they made from the early 90s up the early y2k
  14. Cancerman

    Cancerman Member

    If you are in Florida I can direct you to a guy who remans 4.0's only for around $900. exchange. All the timing chain upgrades with guides, etc. I did min, runs fine, I use it as a daily with muffler mod and cold air. Fast enough to get sideways and tickets in. I'd just fix and drive it or unload it and get a GT with a 5.0. If you own a lift, have lots of tools and experience modding cars, by all means go for it. I bought my car cheap with a dead motor in it.
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