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But how long does it takes to put in a Cummins and do I have to remove some of the parts in the engine bay in order to put in and operate the Cummins?
And is it simple?
Unless you are a mechanic, with some extra time and a shop full of tools, don't even consider doing this. Seriously.
However, if you ARE a mechanic, and want to do something like this "just because you can" (this is why most guys do a lot of the stuff we do), then go for it. It'll be a fun challenge. You just won't recoup your costs.
Last edited by GarageLogic; 12-11-2013 at 09:34 AM..
So it's best to just atay with what I got and find parts for my Suburban such as headers, cold air intake amf good exhaust to gain mpg.
I drove a 6.5 for a lot of years. Good, durable engine as long it wasn't used for anything more than light towing. I would never buy a used 6.5, though. One thing that will screw them up is if they were ever overheated--and they could be fairly easily if they were used for any heavy towing.
The other downside is that the 6.5 is an indirect injected engine. The good news is that injectors and injection pumps for them are relatively cheap, but that indirect injection hurts their fuel economy. In that vein, a far better solution might be to swap in a later model multi-point fuel-injected 5.7 gas--they got almost as good a fuel economy as the 6.5. That still would involve serious $, as I suspect one would have to swap in a new wiring loom, electronic module, etc.
With any swap like that, you will never recover the cost in gained fuel economy--especially with an older vehicle. The rest of it will wear out before you ever can get there. If your current setup is running OK, the cheapest alternative is just to keep it well-maintained and keep driving it.
Don't do it. You will run into hundreds of problems you never anticipated, and you will sink more money into it than a 25-year old Suburban could possibly be worth.
If you want a diesel Suburban, sell yours and buy one that is factory diesel.
Seriously this is the best advice. Cheaper all around than collecting the parts to do a complete job.
I drove a 6.5 for a lot of years. Good, durable engine as long it wasn't used for anything more than light towing. I would never buy a used 6.5, though. One thing that will screw them up is if they were ever overheated--and they could be fairly easily if they were used for any heavy towing.
The other downside is that the 6.5 is an indirect injected engine. The good news is that injectors and injection pumps for them are relatively cheap, but that indirect injection hurts their fuel economy. In that vein, a far better solution might be to swap in a later model multi-point fuel-injected 5.7 gas--they got almost as good a fuel economy as the 6.5. That still would involve serious $, as I suspect one would have to swap in a new wiring loom, electronic module, etc.
With any swap like that, you will never recover the cost in gained fuel economy--especially with an older vehicle. The rest of it will wear out before you ever can get there. If your current setup is running OK, the cheapest alternative is just to keep it well-maintained and keep driving it.
i agree with this, and the others advice. unless you have some good fabrications skills, and swap transmissions, a diesel swap is not for you. as jazzlover indicated a much better swap would be a later model, say late 90s or early 2000s LSX swap instead. it practically goes in place of your current engine, bolts to you current transmission, and you can get an engine swap harness from GM to make the old and new work together. in fact since you were planning to drop a lot of money on the project, diesels are not cheap you know, you can pop down to your local GM dealer and pick up a complete crate engine that has everything you need including the wiring harness and ecu to drop in to your vehicle.
Don't do it. You will run into hundreds of problems you never anticipated, and you will sink more money into it than a 25-year old Suburban could possibly be worth.
If you want a diesel Suburban, sell yours and buy one that is factory diesel.
Quote:
Originally Posted by Electrician4you
This^^^^x10. Adding it all up along with custom fabrication getting ALL the needed parts you'll be dumping 50k in it. Your cost may be a bit less if you find a wrecked truck and buy it whole to have all the tiny little parts you will need. I hope you're a good fabricator.
Quote:
Originally Posted by Merc63
If you bought my '94 6.5 turbo diesel truck for $3k, you could do the work yourself and be in it under $5k. But it would be a LOT of work. You'd have to use the engine and transmission together (it's also an automatic, but a 4L80E, the 700R4 won't fit). And you really won't be gaining that much in efficiency. The later Duramax diesels can be relatively efficient, but the 6.5s weren't as good. Great for towing however, which is what I've used mine for.
^^^ all of these are the correct answers.
Quote:
Originally Posted by Blackandgold51
So it's best to just atay with what I got and find parts for my Suburban such as headers, cold air intake amf good exhaust to gain mpg.
Nope, no big MPG gain and lost of money down the drain. (hey, that rhymes)
Quote:
Originally Posted by GarageLogic
To be honest, you're never going to gain a lot of mpg on an older Suburban, regardless of how much tweaking you do. Because it's kind of "old school Chevy" there is every imaginable after-market part available. And they're not all that high-priced for what they are. But you have to do some serious thinking about return on investment. Is it worth throwing $1000 - $1500 worth of parts on it, to gain 1/2 to 1 mpg?
My suggestion would be to do a complete tune-up. Don't waste money on "ultra-amazing-triple-spark plugs" or gimmicks like that. Just do new plugs, new plug wires (if needed), new distributor cap & rotor, and do a good cleaning of the TBI.
Then, if you want economy, buy a Kia.
Do the tune up only if it needs it.
Get the big bottle of Techron fuel system cleaner and get the carbon off of the back of those valves.
If their is a check engine light on get it diagnosed. (Free at Auto Zone)
You're not going to get great mileage with a 350. End of story. Sorry, I know you don't want to hear it.
This^^^^x10. Adding it all up along with custom fabrication getting ALL the needed parts you'll be dumping 50k in it. Your cost may be a bit less if you find a wrecked truck and buy it whole to have all the tiny little parts you will need. I hope you're a good fabricator.
Actually you are a little off on the price. I looked into paying someone to do the Cummins swap on my Excursion , instead of myself doing it. Dropping the truck off their and having them do everything, including supplying the motor , using my transmission was around $12k-15k. Prices varied on which version of the Cummins you went with and how much power you wanted. Sure you will never recoup the cost but if you have the money to spend sometimes having something useful and unique is worth it.
I ended up not doing it at all since I don't tow that much anymore and the V10 isn't horrible.
If all you want is mileage try something a little smaller than the largest vehicle available.
Unless theres something super, super cool about your sub, it's not worth swapping engines.
I've done several engine swaps, and been around many more. Rarely do they come out as good as the original installation. It's usually cheaper and easier to buy the vehicle with the engine already in it. I'm pretty sure suburbans were available with a 6.2 new.
As mentioned, if you are going to swap in a diesel, a 12v cummins would be a great choice. Thats what I'll do if my 7.3 in my superduty ever wears out.
I've been thinking about switching from my Gasoline 5.7 350 Engine to a Diesel.v
I'm not worried about performance, just effeciency.
And I plane on keeping my Suburban for a long time if-not long time
Also, what are the true advantages of a Diesel vs Gasoline and am I making the right decision of switching to diesel? Amd are diesels as easy to work on as gas engines?
Another thing, I heard and seen diesel engines having a hard time starting in the cold weather.
I live in New Orleans by the way and the weather is like cold in 50-30 degrees.
Also,I have an automatic transmission.
I agree with most that unless you are just doing this for the engine swap experience, it's not worth doing. You could keep the truck as-is, just tune it up good, and use the money you saved to buy a decent Miata. Then you would have the truck for truck type driving and hauling, and a neat little sports car for more daily use.
If you figured the pay back time for doing the Diesel conversion, even if you could do all the work yourself, just a good junkyard engine and tranny would cost enough that it would be years before you made your money back on the conversion.
Actually you are a little off on the price. I looked into paying someone to do the Cummins swap on my Excursion , instead of myself doing it. Dropping the truck off their and having them do everything, including supplying the motor , using my transmission was around $12k-15k. Prices varied on which version of the Cummins you went with and how much power you wanted. Sure you will never recoup the cost but if you have the money to spend sometimes having something useful and unique is worth it.
I ended up not doing it at all since I don't tow that much anymore and the V10 isn't horrible.
In the Hot Rod power tour this year there was a 1969 (?) Suburban with a Dmax in it. It was really cool.
With a rebuilt motor? Used motor? I would never do a swap without rebuilding the motor and trans. If I want a diesel I would buy a car that has one in it from the factory
Location: We_tside PNW (Columbia Gorge) / CO / SA TX / Thailand
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Lots of things to think about... swaps are not ez or cheap.
IF you have a perfect Suburban, I would suggest the 12v Cummins as a way to go. There are many Suburban>cummins swaps and blogs available. There are many conversion shops in nearby TX, as well as very cheap CTD (Cummins Turbo Diesel). I buy out of San Antonio or Austin, usually for under $2000 for a complete donor truck (you want this, not just an engine). http://www.dieseltruckresource.com/
I would use a DTT tweaked Dodge Tranny w/ OD or a 6 speed manual.
These guys in Comfort, TX are awesome diesel heads. 830.995.2121
They can build you a fire breathing dragon that will get 18 - 22 mpg. *That is what I get in my CTD dually 1T 4x4's (I have 3 that are 12V). The absolute best donor is a 97 or 98 (early 12V with a P7100 pump). You will go a million miles with your cummins (with reasonable boost... NOT 40 - 80 PSI!!!).
The chev conversion is just not worth the trouble, you can BUY a diesel suburban and save many headaches and dollars.
WARNING: It is best to have a diesel passion to own / drive a diesel. They are not for the faint of heart (or those that don't like smoke, soot, noise and smell.) If N.O. is anything like Central TX, you will have an abundant supply of FREE Waste Cooking oil for free fuel or feedstock to make BD. It does not smell or soot, tho you will be like a 'piped piper' with a train of people following you looking for French Fries or Fish and Chips. The MAINT issues are WAY blown up by those who don't know... Fresh Fuel and Filters (I change mine 1x / yr) will take care of 90% of diesel needs. NO ignition / plugs, carbs / computer... The issues of FINDING diesel fuel are also largely unfounded. Got a smart phone and 'gas-buddy?'... (Lists Diesel). but just brew your own... you don't have to fill too often... a 40 gal tank and 20 mpg gets you a bit down the road... I go 1250 miles / fill on my 25 gal VW Passats.
As a farm kid... I can't get rolling in the AM without a snort of diesel (I don't do coffee). 39 of my 40 vehicles are diesel (4-18 wheelers) I keep a few GAS (ICK) Motorcycles around the farm. and a gas lawnmower, till I can find a diesel one CHEAP.
Last edited by StealthRabbit; 12-13-2013 at 12:16 AM..
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