What Trans for a cummins swap c10?

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legopnuematic

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Another thing to consider is that your truck has some vacuum controlled components on such as the HVAC system, brake booster and cruise control (if equipped.) for the brake booster, you can do a hydroboost conversion, for everything else you’ll need to rig up a vacuum pump and run the lines accordingly.
Until 2003 (third gen rams) Cummins in Dodge trucks had vacuum pumps. Vacuum brake boosters were used on them until 1996 or 1997, then they switched to hydroboost. So that shouldn't be an issue. They also use Saginaw style power steering pumps similar to what squarebodys use.
 

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To go with what has been said about the vacuum pumps, the only ones I would NOT use is the 1st gen non ic diaphragm pumps, unless I had to. Parts are getting harder to find for them, and they are not as reliable.

The 1st gen ic and 2nd gen 12v pumps are the better ones to use.
 

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Also remember the bell housing adapter that bolts to the block must match the transmission. On 1st gens, the auto and manual ones are different, and of the manual trans one, the G360, NV4500, and G56 ones are different from each other, and require different flywheels / clutches and starters.

Then you can get into the Advance Adapter kits, which is a whole other can of worms.

Also, if I remember right, the 3rd gen (G56) bell adapter will bolt to a 12v block, but 2 bolt holes do not line up.

None of these standards are performance street transmissions, as you mentioned building the truck as such.

Have owned, and swapped every gen of Cummins, and currently own a 3rd gen with a G56.

If I don’t get rid of my 88 v3500 CC, and build a Cummins for it, I’d probably p pump a 24v with an NV5600, but it would be for pulling. (Sold my last gooseneck trailer a little over a year ago, so doubt that will happen. Plus, I need my left knee replaced. I have never owned a daily driver that wasn’t 3/4 or 1t, and all were standard trans with usually an aftermarket clutch. I look forward to having something with an automatic)
 

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A 12 valve isn’t the hardest swap you can do, though since you’re starting with a 1/2 ton, you will definitely want to beef up your frame and suspension. Granted, many 1/2 tons came from the factory with the 6.2 Detroit diesel, which isn’t exactly a lightweight engine, so the marginally heavier Cummins probably won’t be too punishing, but I’d still recommend some sort of reinforcements.

As for the transmission, the NV4500 is a solid choice, though it’s not native to square body, so you’ll have to fab up things like the entirety of the hydraulic clutch assist system.

Another thing to consider is that your truck has some vacuum controlled components on such as the HVAC system, brake booster and cruise control (if equipped.) for the brake booster, you can do a hydroboost conversion, for everything else you’ll need to rig up a vacuum pump and run the lines accordingly.
Vacuum pumps are pretty standard stuff since newer stuff and stuff of that era don't use cables. But that is a very overlooked/not thought about problem when doing a diesel swap. Good point to bring up.
The cummins engine has its own vacuum pump built in. The port is by the power steering pump on drivers side. I have mine hooked up to my brake booster and works great.
 

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Until 2003 (third gen rams) Cummins in Dodge trucks had vacuum pumps. Vacuum brake boosters were used on them until 1996 or 1997, then they switched to hydroboost. So that shouldn't be an issue. They also use Saginaw style power steering pumps similar to what squarebodys use.
For a 12 valve out of Dodge, this is applicable, but for one out of a medium duty Ford, the power steering pump is is gear driven behind the crank case and the vacuum pump is 12 volt firewall mounted unit. It’s a pretty safe bet OP is getting his engine out of Dodge, but there are quite a few Ford spec ones in circulation too.
 
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squaredeal91

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For a 12 valve out of Dodge, this is applicable, but for one out of a medium duty Ford, the power steering pump is is gear driven behind the crank case and the vacuum pump is 12 volt firewall mounted unit. It’s a pretty safe bet OP is getting his engine out of Dodge, but there are quite a few Ford spec ones in circulation too.
I forgot about medium duty Fords lol. Good point. Electric vacuum pumps do work. I might have to get one for my Mazda when I convert my alternator to a delco because the vacuum pump is attached to the original alternator and im done with making it charge
 

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I forgot about medium duty Fords lol. Good point. Electric vacuum pumps do work. I might have to get one for my Mazda when I convert my alternator to a delco because the vacuum pump is attached to the original alternator and im done with making it charge
I’ve got an ‘03 (i think that is the right year) Dodge one on my 84 K10. Also I believe Ford used the same electric pump from about 99 - up on the diesel Super Duty trucks.

May be worth looking into, as they are easy to find and inexpensive.
 

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Back to original question. thinking about it being a 2wd street truck the ZF5 isn't a bad option as it does shift faster than others. You can actually speed shift it. I wouldn't even consider a G360 because of torque.
 

Vbb199

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Yep, Having a stick shift vehicle with a bench seat never stopped any females from sitting next to me. And yep, fun times.

See this is where im trying to take my frame swapped, 4200/5 spd c10.

A 5 spd with a bench so my wife can sit next to me! (Altho she could when it was a big block 3 spd)

Which is precisely why I really came here to say OP, I put a 800lb motor in a c10 and it did squat the half ton coils down, but not as extremely as some of these people are saying or perhaps expecting
1200lb cummins.... mmmm yea you'd wanna get yourself some 3/4 ton goods at least

Not sure if youre trying to lower it or what, iaintgoingbackandreadingallthatnow

But if you are, definitely land some 3/4 ton coils so if you want to drop it, its not going to flatten all the spring rate out and make it a stiff pos up front.

I do definitely think you'll want to consider like a rear gas tank from a burb or something to take that noise weight off from the heavy arse motor.... or some lead in the frame there... I dont know but driving a fast a$$ c10 with a 800lb big block , th400..... with cut half ton coils and spring flipped rear wasnt too bad. It didn't scare me nearly as bad as newer shyt does at over 100 mph.

Definitely want to look into some rear weight counter balancing though. No doubt

As for a trans why not the nv4500?
Just be on the lookout for dudge 4500s with the 5th gear nut backing off and destroying 5th.

My buddy ran a nv4500 behind a modded 12v and it was a real monster.

The zf? I dont know, I dont think theyre all that for bigger hp but maybe im not informed enough.


Theres another alternative, which is a frame swap which would be all around a better idea...
Just keeping it 2wd with 500hp on a diesel is gonna be alot tougher than someone (me) who kept together in a 2wd with 500hp gasser
So.. food for thought there... I ditched my stock frame for a tahoe frame which can withstand the power numbers im seeking which is beyond 500hp.

I think one battle you'll experience is the length of the motor or something. So ive heard. Like some firewall editing required.

I looked into this for my k5 I was putting together years ago, so I have a little info on it .. but that was another level of trucking there.
 

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I have a classmate that has had at least one diesel conversion done to one his old Ford 4x4's. I haven't seen or spoke to him in almost 30 years, but back then when he sent off the truck to be converted, when it came back it was nice. Not a race truck, but plenty of power. Granted this was 3/4 ton 4x4 Ford, but at minimum, 3/4 ton suspension and/or frame is the key.
 

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I'd take a hard look at an 89-93 regular cab 8 foot bed Dodge. Make body mounts and do a body swap. I think it would probably be less work and better results.
 
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CheemsK1500

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I'd take a hard look at an 89-93 regular cab 8 foot bed Dodge. Make body mounts and do a body swap. I think it would probably be less work and better results.

At that point he might as well just sell the C10 and buy the Dodge, unless the Dodge in question is in exceptionally awful condition but still has a good frame.
 

Ricko1966

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At that point he might as well just sell the C10 and buy the Dodge, unless the Dodge in question is in exceptionally awful condition but still has a good frame.
The exact same thing could be said about the plan to buy a dodge truck,swap the engine transmission,and rearend into the chevy chassis,buy or build all the mounts and crossmembers,swap out the front suspension and make any necessary reinforcements. So everything underneath and power train wise would be Dodge except the frame. So just sell the Suburban and buy a Dodge. I think his end goal is to have Chevy square body style with a Dodge drive train. A chassis swap seems like a better,cheaper and easier way to accomplish the same thing. IMHO.
 
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1low4x4

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To be fair a trans probably has zero idea about mechanics much less how to retrofit an entire engine/drivetrain
 

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