Gas to diesel

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jr22

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1986 K20 gas to diesel. I’ve been throwing around the idea of putting a diesel in my truck. Is that something I could do? Is it pretty expensive or should I just look for a diesel truck?
 

Rickf

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Depending on your skill level you can do it, however it's probably quicker and cheaper to buy a diesel truck.
 

K5 Blazer

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I am sure someone has done it by now. I would do your research and see if there is a good video or thread to follow. It will be so much easier to learn from other's problems before you have to figure them out for yourself.
 

vr1967

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Are you wanting to go to a 6.2/6.5 GM diesel? Or Cummins swap? I’ve done both several times.

What is your intended use for the truck?
 

77Dmax

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Hard to beat a duramax swap.
 

vr1967

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Tuna fishing off the coast of mexico :waytogo: :anitoof:

I love it when people ask that question :eek:
If it is a daily with very little towing, the 6.2/6.5 would be an easy swap. If you plan to pull a 65-100hp tractor regularly, I’d suggest a Cummins swap.

Do you have anything constructive to say? You seem to grumble about most things on here.
 

Ricko1966

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Lots of people on this forumn have done diesel swaps,I'm doing one myself. Look in the engine swap section you should find plenty of info. As for is it expensive,that's going to depend on what kind of deals you can find for your parts,same as any other engine swap. If you can score a rusted out beater truck with a good drivetrain for cheap that's the way to go. Imho. I scored a low miles 6.2 with a rebuilt 4l80e for $600.00 and drove it home.
 

JD Miller

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Do you have anything constructive to say? You seem to grumble about most things on here.
:happy175: LOL !.... "Lighten up, Francis":Pshyco:.... You're wound a little too tight.

You should be less serious and make an effort to be more relaxed and happy.:pepper::dancingpoop:
 

Ricko1966

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If it is a daily with very little towing, the 6.2/6.5 would be an easy swap. If you plan to pull a 65-100hp tractor regularly, I’d suggest a Cummins swap.

Do you have anything constructive to say? You seem to grumble about most things on here.
He only called you Francis,you should see what he called @fast 99 and @TotalyHucked
 

jr22

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If it is a daily with very little towing, the 6.2/6.5 would be an easy swap. If you plan to pull a 65-100hp tractor regularly, I’d suggest a Cummins swap.

Do you have anything constructive to say? You seem to grumble about most things on here.
I was thinking an early 2000’s duramax, like an 05 or 06. Are those good years? I want to keep it GM
 

Ricko1966

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I was thinking an early 2000’s duramax, like an 05 or 06. Are those good years? I want to keep it GM
Have you tried typing the word duramax into the search tab there is plenty of reading there. It will give you lots of information,and things to think about.
 

Grit dog

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1986 K20 gas to diesel. I’ve been throwing around the idea of putting a diesel in my truck. Is that something I could do? Is it pretty expensive or should I just look for a diesel truck?
Pretty open ended question. Not to mention we have no idea what your capabilities and resources are.
I think a 12v or 24v swap would be great in a K20.
I wouldn’t waste the WiFi even thinking about downgrading to a 6.2. Especially at altitude where you may well drive. Mileage will be nice. Power will be horrid.
But at least it will be less complicated.
Judging by the nature of the question, I’ll say you’re probably in for a big challenge regardless if you use a milquetoast drop in old GM diesel or try to tackle a Dmax swap. A mechanical injection Cummins transplant is the best combo of low cost, ease of application and big power with good mileage.
 

legopnuematic

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The answer is a 4-53T 2 stroke Detroit of course.
You must be registered for see images attach


For simplicity, and ease of the swap the a Cummins really is probably the best way forward.

Duramax’s are cool, but they kind of are a packaging nightmare, compared to an inline engine imo.
 

TotalyHucked

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The answer is a 4-53T 2 stroke Detroit of course.
You must be registered for see images attach


For simplicity, and ease of the swap the a Cummins really is probably the best way forward.

Duramax’s are cool, but they kind of are a packaging nightmare, compared to an inline engine imo.
You joke, but I wanna do that one day. It makes no sense, will make no power, get terrible fuel mileage lol...but they sound so good

To the OP, that's a tough question without knowing your skillset. I'm a pretty good wrench and know my way around vehicles pretty well, done/helped with several LS swaps now and worked on a myriad of stuff over the years. As stated earlier, I wouldn't bother with a boat anchor of a 6.2. 6.5 Turbo, maybe. Cummins, absolutely. The Duramax would be fairly involved. Not that I wouldn't go down that road, but it would require lots and lots of research. It's been done enough times that the info is out there. Start Googling and start reading, decide if that's something you're up for. There's alot more electrical involved in a Duramax swap
 

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