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I have a 98 Chevy k1500 that currently has a 5.7 vortec. I would like to do a diesel swap into it. I am looking for something that would do great on mpg but would also be able to tow as well. I wouldn’t tow more that 5-7 times a year and the most I would tow would be a boat or small camper. Camper weighs 2300lbs and a boat roughly 4-5,000lbs. If someone could help me decide what’s the best rout for a diesel swap. Would a 4bt Cummins do the job for something like this without having to swap to 3/4 ton axles and stuff like that?
 

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What type of MPG are you getting currently with the 5.7? I don't think it makes sense to swap out the drivetrain for MPG in your use case 4bt's are getting quite rare nowadays and you will likely never recoup fuel savings with your scenario with the swap.
 

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What type of MPG are you getting currently with the 5.7? I don't think it makes sense to swap out the drivetrain for MPG in your use case 4bt's are getting quite rare nowadays and you will likely never recoup fuel savings with your scenario with the swap.
I am currently averaging 10 mpg with the 5.7. But besides fuel saving cost what about towing increase. The 5.7 I have now is weak and can’t pull anything. It’s a new motor and tranny as well. What diesel swaps would you recommend other than the 4bt
 

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I am currently averaging 10 mpg with the 5.7. But besides fuel saving cost what about towing increase. The 5.7 I have now is weak and can’t pull anything. It’s a new motor and tranny as well. What diesel swaps would you recommend other than the 4bt
I’m not only looking at the standard 4bt but all 4bt models like 4btA and 4btAA
 

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U might want to put the 5.9 in if you tow a lot. Also depends on your gearing, tire size, etc. Plan what u want, the 4bt has less margin for error. Also keep in mind these swaps get costly.
 

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They don't get much love in the diesel world, but hands down the easiest swap is going to be a 6.5L td and it's related trans. An H1 would be the likely best donor, but can live with an R/V2500 donor. It should literally bolt in. The electric might take a little sorting, but the mechanical should be mostly off the shelf parts. In your described use where it won't be worked too hard a healthy engine should live a long time.
 

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I agree, a 6.5 diesel would be a good option, very low cost, no need to change anything else. Cost would be low. No need to change axle ratio, which must be high based on gutless performance.

Ed in CO.
 

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The answer to your 1st question if the 4bt would be adequate is yes. May need to adjust the power a bit but you aren't talking extreme towing levels. A 4bt adjusted to around 200 HP should be more than sufficient. Another thing you would want to look at are your axle ratios and transmission. The torque point where these engines like to run is in the 1700-2000 RPM range. They can run faster but fuel mileage will suffer. What transmission do you currently have? If you are looking at a swap from a cost savings stand point, you may never recoup the cost unless you drive a lot of miles. First in the line will be the cost of the swap itself. A moderate guess would be in the $8000 up range. Cost accumulates very fast when you put a swap together. Operating costs are also higher for a diesel. Typical fuel mileage can be in the 20-25 MPG range which is about double what your gas engine gets. Some of that gets offset because diesel costs more that gas, the engine holds twice as much oil, and fuel and oil filters generally cost more. Back in the day when I bought my first diesel pickup, I calculated that it would take me 100,000 miles to recover the $2000 extra the engine cost. That was when diesel was $.40/gal cheaper than gas where now it's like $.40/gal higher or more. Nothing wrong with doing a swap but few if any are done from a pure cost savings point of view.
 

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I agree with char1355. When you calculate the cost the conversion may not make sense. Given the situation I would consider buying a truck with a conversion already completed,or a dodge with an 12v.
 

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It isn't practical to convert an engine from one fuel to another, but you can change engines. If the vehicle is available in either gasoline or diesel versions from the manufacturer, you just need the engine, and any other parts that are different.

 

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Not sure which state you are in but switching your registration over to Diesel could be a problem as well. Buy a dodge w 5.9 (or Chevy 6.6) and spare yourself the headache. The swaps aren’t worth the savings anymore as char1355 stated. I started mine when Diesel was cheaper than gas, by the time I finished it switched.
 
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