Big Cam Cummins reliability

Discussion in 'Ask An Owner Operator' started by freebird95, May 27, 2018.

  1. freebird95

    freebird95 Light Load Member

    Feb 17, 2015
    Hi everyone just had a few questions about the old Big Cam Cummins. Im looking into buying my first truck and am wondering about how reliable the big cams are. How long can they run before needing a rebuild? I have heard that the cummins parts are cheaper compared to cat, thats why im considering a cummins over a b model. just looking for any advice and opinions are what to expect since i only have experience with a red top
    jamespmack and OLDSKOOLERnWV Thank this.
  2. Dino soar

    Dino soar Road Train Member

    Dec 8, 2017
    Best engine ever made. But you have to start with a good one. You might be able to rebuild that engine several times for what it would cost you once to rebuild a caterpillar. And no expensive Central distribution type injection pump. Don't be afraid to buy a brand new crate engine or have someone work you over an engine with new everything when it is time. It will be the best investment you ever made in your life. Very dependable and easy to work on. If you drive a big cam 400 and feel how it pulls you'll be hooked forever.

    Big cam 1 2 3 is good. Stay away from big cam 4 because they had low flow Cooling and it caused a lot of problems and it's expensive to change over.

    Like I said, best engine ever made. You'll laugh at all the electronic junk out there as you pass them while they're broken down with an electronic problem. You will keep a lot more money in your pocket as they blow large amounts of unnecessary money on wires and computers and expensive injectors and complete stupidity and visits to the dealer. No visit to the dealer is ever necessary with that engine. Electronic injectors are somewhere around $400 a piece. I get big cam injectors for $65 a piece last time I bought them. Very inexpensive, reliable, and Powerful engine. You are an intelligent man to pursue such a path. Much more intelligent than many others.

    Greatest engine of all time.
  3. slickWillie1980

    slickWillie1980 Medium Load Member

    Sep 2, 2015
    Mt Olive, NC
    Don't be scared of crate 400 BC at Carolina gear in Raleigh will run you about 11k. You can't even get an inframe on a Cat or Detroit for that.
  4. Ridgeline

    Ridgeline Road Train Member

    Dec 18, 2011
    Best engine ever?

    Nope, it is as good as the other engines.

    Let's be real, you need to do the same due diligence than you would with any other truck.

    Even 6-71 detroits are good engines

    If you are to run the truck, parts in stock and mechanics who know anything about diesels are going to be the problem.
    Oldironfan and Tug Toy Thank this.
  5. stillwurkin

    stillwurkin Heavy Load Member

    Dec 2, 2017
    Best engine ever..??? They are good but not that fantastic. Fuel mileage not as good as say a 12.7 or even a older 11.1 detroit. Power is more comparable to a 11.1 60 series 350 hp. Now i will see comments about how they outpull 425 cats and 12.7 or whatever. You can fuel up any engine and make it pull, the old big cams were not really a powerhouse.
  6. Dino soar

    Dino soar Road Train Member

    Dec 8, 2017
    Everybody has an opinion and I respect that.

    But yes the Cummins big cam is the best engine ever made. The next best engine would be a Detroit 2 stroke. The next would be any mechanical engine. And the very very last would be any electronic junk that has unnecessary garbage on top of a mechanical engine that only cost you money.

    The only reason the Detroit 2 stroke is second on the list is because it's harder on fuel and you have to change oil more often. But the two stroke is a way better engine than any of that electronic garbage. Legendary reliability. So reliable in fact is most of them weren't even serviced right because they just kept going and going and going and going.

    The reason why the Cummins big cam is the best engine is because it's a modern four stroke diesel that will do what any other Modern Diesel does these days except it does it without a computer and all the expensive worthless non needed BS.

    It does it without EVER going to the dealer, with inexpensive rebuild kits, and inexpensive injectors. Very very reliable, inexpensive to run, and easy to work on and maintain. That's what makes a good engine.

    As one of the gentleman said, you can buy a whole crate engine for less than an in-frame on the electronic junk. And by the way that's only the mechanical part, if you add all the electronic nonsense on to those engines your cost goes up and up and up and up. And that in frame is really only Pistons bearings and liners. There is a lot more to those engines than just that. But with the Cummins big cam you can have a whole brand-spanking-new engine 4 less than the in frame on the other junk.

    They are easy to turn the horsepower up if that's what you need and they can be built to what 800 horsepower a thousand horsepower? The design was so brilliant that they kept it right through the n14 which is basically the same engine, although you will notice just about everything is more expensive on the n14.

    I just have to shake my head because I can't understand why on Earth anyone would want an engine or think that a good engine is something that requires crazy stupid Electronics that will leave you stuck somewhere at a dealer where you have to spend a fortune to fix it. And how many guys have been to multiple dealers trying to figure out what's going on? They are not simple inexpensive engines that you can fix yourself. They are like a bad woman that will take you for broke if the Wind Blows the wrong way.

    I've been on I-5 in California doing 20 miles an hour because a stupid speed sensor went out. Not only is that an unnecessary expense, it's dangerous, and the hell of it is nothing like that could ever happen with a Cummins big cam. It's just an unnecessary repair for an unnecessary part for you to spend unnecessary money. That to me is worthless junk.

    I don't know about anybody else but I've spent time on these forums and the repair forum. Every time one of these engines has some kind of electronic problem in a blink of an eye it's $5,000 or $10,000. There are guys that take their trucks to multiple shops and multiple dealers and could have probably bought several other trucks and bought crate engines and put them in them for the money that has been completely wasted on this unreliable stupidity.

    Like I said everybody has their opinion. But in a business where everybody cries they can't make enough money, where insurance is like putting a mortgage on your house, where only DOT fines rival insurance cost, why on Earth would you want to empty out your wallets for electronic nonsense?

    If you don't believe me read the forums.
  7. slickWillie1980

    slickWillie1980 Medium Load Member

    Sep 2, 2015
    Mt Olive, NC
    There ain't nothing like a Hummin' Big Cam Cummins
  8. Mattflat362

    Mattflat362 Road Train Member

    Feb 18, 2015
    Avon Lake, Ohio
    I friggin love my BC4...low flow and all!

    I would love the part numbers needed to convert to high flow someday though....should it ever give me grief.
  9. stwik

    stwik Road Train Member

    Oct 8, 2017
    USA USA USA!!!
  10. Rubber duck kw

    Rubber duck kw Road Train Member

    Dec 9, 2017
    I think the reliability part of them goes away when you start talking monster horse numbers but you should be able to get 500 out of it and still drive it all day every day.
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