Diesel Questions

[Car'n'Guitars]

Okay so I'm looking to do a Cummins swap in the near future, but I have a few questions that need answered first. First question, is it easier to swap a Cummins into a previous diesel Chevy compared to a gasser? Second question I'm finding it kind of hard to find K20's and K30's around me. Is there any real difference between the K20's and CUCV's? Or the K30's vs the K20's? And last what does everyone think would be better to do the swap into a regular cab long bed or a crew cab long bed? I'm kinda split right now on either option so I need convincing either way. Any help would be appriciated guys.

[Edahall]

The advantage of installing a Cummins in a previously equipped truck is it'll already have hydroboost brakes and 4 core radiator. They may also have gears more appropriate for a low revving high torque engine.

As far as regular vs crewcab, there are a lot more conversions using crewcabs out there. Regular cab conversion would be more unique. Very unique would be regular cab short box.

[48cj2a]

The CUCVs are just a K30 with no frills and a special wiring harness for the 24v starting system, dual alternators, blackout lights, TH400 trans, 208 or 205 transfer case depending upon model, 4.56 gears and a Detroit Locker in the rear. M1031s had a TruTrac locking diff in the front an all had the NP205.

The CUCV Blazers are a no frills Blazer with the same specs except 1/2 axles, 3.08 gears, and GovLoc limited slip rear and rated at 3/4 ton suspension

[Car'n'Guitars]

So heavy duty wise either or wont matter? And now i guess i just play the hunting game.

[Edahall]

Originally Posted by Car'n'Guitars

So heavy duty wise either or wont matter? And now i guess i just play the hunting game.

It depends on what you want to do with the truck. If you're going to be doing heavy duty off roading or pulling with the engine pumped up to insane power levels, it'll matter. But for everyday highway driving, even 1/2 ton is strong enough.

[Car'n'Guitars]

Power, and itll be used for work too. It will eventually be p pumped and built.

[farmall]

I would not do a Cummins in a K20 front axle wise.

[Car'n'Guitars]

Why not?

[farmall]

1000 lbs sitting on a half ton axle housing?

All that torque through a half ton ring and pinion and axle?

Dodge and Ford never did.

[Car'n'Guitars]

Okay I was thinking the K20's had Dana 60's

[Corts60]

Many half tons came with the 800 LB Olds 350 and 750 LB 6.2 diesel. Those 1/2 ton axles should have no problem supporting an extra 100-125 LBS per side.

I will be putting a 5.9 Cummins in my 2wd half ton short box and the only thing I will be beefing up will be the steering bracket so the frame doesn't crack under the weight. All factory 1/2 ton diesel trucks came with 3/4 ton springs and heavy duty brakes (2wd anyways).

[Car'n'Guitars]

I want heavy axles and frame, something that i can actually use the Cummins with. So i should be lookimg for a K30 not K20?

[andrewmp6]

A k20 has a dana 44 or 10 bolt front axle depending the year.Only thing factory with a dana 60 was a k30.Now you can swap in a dana 60 in a k20 or even k10 if you want it.Have you looked around http://67-72chevytrucks.com/vboard/f...play.php?f=240

[Car'n'Guitars]

Yeah Ive started to look around but I was under the impression that K20's had Dana 60's up front not 44's. That being said would the crew cabs have 60's or 44's?

[86c20]

k10 will have 10 bolt k20 44 or 10 bolt maybe 12?? k30 d60 nothing else. one down side to a dana 60 and 14 bolt lowest gear combo is 3.54 so you will need a real good over drive or big tires to go down the highway at speed without the motor tached out

[Car'n'Guitars]

I'm fine with that a 99 Dodge Cummins is my daily driver so I'm used to that. Now I need to look for a truck, but is a CCLB SRW considered a K20 or K30?

[farmall]

6.5s weigh 650 dry. B6 is 1100 lbs dry.

[Car'n'Guitars]

You mean 6bt's?

[farmall]

Yea. Its early here.

[Car'n'Guitars]

Haha okay just wanted to make sure i wasnt missing anything, and its early for me too.

[79Betty]

CCLB are all 1 ton's

[Car'n'Guitars]

So they would definitely have Dana 60 fronts?

[Edahall]

Most 1 ton trucks are geared too low for a Cummins unless you plan to use monster tires or have very limited top end speed.

[Car'n'Guitars]

Gearing is not my question here, i am constantly around 4 Cummins trucks so I know how they drive i am completely satisfied with that. I just want to make sure I get good axles.

[Edahall]

Originally Posted by Car'n'Guitars

Gearing is not my question here, i am constantly around 4 Cummins trucks so I know how they drive i am completely satisfied with that. I just want to make sure I get good axles.

You need to define good. Dana 60 axels with 4.56 gearing might be good for mudding but not for going down the highway at 60 mph or getting good fuel economy.