78 crew cab + 06 ccsb 4x4 duramax/allison combo = which route to go?

[BK]

Hey all. Just picked up a 78 crew cab 2wd with a knock for $300 in really good shape, light blue with white stripe. Anyway, it was too good of a deal to pass up. I've wanted a crew cab 4x4 for years, so I figured its time to try to make it happen.

I just came across a (what I believe to be) killer deal here locally. A sub 100k mile 06 ccsb duramax 4x4 that was rolled. Cab and bed have been removed, but everything was done properly, with plugs unplugged and nothing at all cut. Guys asking $2000. Its missing a transfer case(his other truck needed a t-case).

My goal for this truck is a driver, with more than likely a sled deck flat bed(big time snowmobiler), lifted a bit, long distance driver, and for hauling the wakeboard boat around.

I'm leaning towards putting the 78 cab and front end on the duramax chassis, without the bed. This will allow me to get the cab as low as possible, as I've heard the rear frame rail kick up leads you to run the cab very high. By running a flatbed, it will allow me to run the cab as low as possible(I hope). Then I can build a flatbed with a headache rack, atv winch built in for when sleds blow up, flip down small sides for room and wider sleds, and a slide out ramp underneath with some tool boxes.

The other option is finding a 4x4 cclb square chassis and swapping the duramax and appropriate parts into that, I suppose with fully boxing the frame and hoping for the best, but I feel this is a step backwards.

I would rather not have to stretch the frame to match the factory cclb wheelbase as I won't be using a stock bed, hoping proportions won't be off. It looks like I'll be trying to incorporate the bcm into the truck as well, as from what I've read, the 06 uses the bcm for cruise and tap to shift, as well as some other functions. I have the complete donor cab and box, minus the two passenger doors.

Can anyone give me input on my ideas? I'm looking for holes in my plan, things I've overlooked, experience issues, or if anyone has pics or build threads on squarebody duramax body swaps, please lend me info or pics. Thanks guys!

[BK]

Here's a picture of the truck!

[nekkidhillbilly]

well I do know a lot about this. since I had planned to do the same but I after having a dmax for 10 years and the issues and upkeep cost I wouldn't have another dmax again.

ok on to the real thing. using the new truck frame. first its ifs and its a junk. second its wider the floor pan area is different so I wouldn't even start to use it. now onto option 2 swapping frames. well yeah you could but that seems like more work than needed. your still going have to build custom motor mounts and cross members and you run into a bunch of issues using a np205 with a Allison dmax combo. the easiest most cost effective way when I was looking into this swap was to take the dmax Allison and lhd transfer case from the new truck and put it in the square. I know I know its lhd and squares are rhd. to solve this you need a ford or later dodge front axle. a ford dana 60 is a direct swap certain years. the dodge you will need to have some welding done for perches and some of the fords. now since your doing this anyhow you might as well rather than swap frames take the 2wd one you have drill holes for the front springs and change the steering comps over. then its a matter of cross members being built which would be out of square tubing and having new drive shafts made. oh you will have to change the floor pan center hump out for a 4wd one or do a body lift. now if you want th tap shift and all that you need the bcm, its harness, and if you want to see what gear your in you need the message center portion of the cluster. which is the cluster board and a very small led read out. you don't need anything but that if you want your oem gauges. you need a electric speedo and never looked into the ac set up if you want that.

scared off yet. these are just what I came through in planning stages. for a engine that will cost 2k in repairs for simple things that should cost a few hundred. water pump is 400 for the part and a 8 hour job. glow plugs and glow plug modulator is about 1800 for both and requires a dealer to flash it. my personal op is to stay with a gas motor or use a ctd. that's just me though.

other things you will run into is swapping filler necks to diesel ones. turbo plumbing and cooling systems. deleting any vats out of the ecm. changing shifters for th and tap shift. wiring in cruise control switch. oh you need the right gearing in front and rear ends or your Allison will go apesh!t. rear is 373 idk what the front is. prepare for a 5 figures of your money to disappear.

[nekkidhillbilly]

my advice is go find a 06 body and build a 06 truck if you want the duramax. would be miles ahead in money. you could fix the 78 and do the 06 and have a pocket full of money. very nice 78.

[daddyjeep]

I love the idea of a D-max in an old Chevy, but I have heard they are very expensive to pull off as hillbilly pointed out. Cummins swaps are quite common and would be significantly less expensive if you really want to go diesel.

[andrewmp6]

Nekkidhillbilly your way off on the front axles btw,Gm used 32 inch wide spring pads,79 back ford used 31.5 inch wide and 85-97 ford used 36.5.The leaf spring dodge is a 1/2 inch wider that make spring bushing adapters to use that but the leaf spring dodges are passenger drop.The 94 and newer dodge is drivers side but its a coil spring axle,Its a CAD axle and a unit bearing axle.Back to the OP either way you do its a monster of a job and a lot of money to pull this off.Can you weld and do you trust your life on your welding skill?Do you have the space to do this,Do you have the time?Your looking months maybe a year in the real world before youll have it driving.Like said a 12 valve cummins is a simpler swap because no ecu and wiring it like 6 wires.And they make swap parts to do this.If you do it either way start a build threat on here.

[BK]

Still looking into all different options at this time. Almost want to do it just to prove naysayers wrong. May have located a proper k30 4x4 chassis which may make me opt for an ls variant, but I won't know until next week. Along with the duramax I got, also got an avalanche with a front end collision, but a low mileage motor and rebuilt tranny, a 6.0 needing a rebuild, and a 4l80e. The 5.3 combo from the avalanche is more than likely going into an fj40 build I'm starting in a month. I may build the 6.0 and 4l80e for this truck. Still weighing options.

I do appreciate you guys being very forward and up front with all the headaches. I see these ridiculous keyboard mechanics telling me stuff like they are putting a 4bt in a 1st gen toyota all the time, when they can't weld and asked if they can get 8" of lift with shackles.

Little background, 31 yr old Wyotech grad, used to be an ASE certified tech in electrical, mechanic and restoration shop owner, with a 60x40 shop. Also, here are some past projects done fully by me for both myself and customers.

Custom cbr, fabricated swingarm and shock mounting, narrowed swinger, custom tank tail subframe etc.


My 65 panel, chopped, shaved, bagged, z'ed frame and step notch with watts link from 2004.


Corvair rampside pickup that I bagged with stepped, narrowed, and angled control arms, and installed the turbo Corvair motor.


Factory five 818r kit car build for a customer .




69 firebird total build - bored stroked 400 with demon tripower, 5 speed, ride pro e3 air ride controller, 4 link, rear disks with Wildwood front, lots more.


My bagged 78 c10.


And my daily driven work rig, 86 4runner, which I widened the control arms 3.5" per side. I bomb this thing down backroads at 45+, jump it, wheel it, daily it. It goes up on the lift once a month to check it out, no issues in two years.

[andrewmp6]

Have you seen project nightrain on trucks ?If https://www.powernationtv.com/episod...in-diesel-swap it is a 2wd 1/2 ton but the motor does fit with work.But having a 1 ton 4x4 you might get away with making a engine crossmember or notching it vs notching the oil pan like he did.For less a wiring headache http://www.btdieselworks.com/product...wiring-harness
For a intercooler you might get away with using a 1st gen powerstroke or 2nd gen cummins maybe.

[74CustomK20]

I've been watching this. You got the skills I'd say, and those last projects look awesome... Especially the corvair since you want a flatbed and I assume plan to actually use the truck, I would try n wedge the motor trans and etc onto the 78 frame. Ifs on those body style trucks are plagued with problems.

[84chevyguyid]

Check out this 66 GMC/Cummins pickup. Met him at the dunes this summer so I got to see it in person. He loved his 66 but wanted it to perform like a new truck so he bought a new dodge and cut it down to the firewall-floorboards-back wall up to the rear window and grafted the 66 sheetmetal to it. The thing is cool as hell! I liked his comment, "When it was all done I climbed in, hit the key and drove off with a new truck. No issues with mating wiring, trying to make this component work with that component, ect." He said he only had to extend a few light wires a few inches was the only wiring he had to work on. Maybe another way to go on your project?

http://www.trucktrend.com/cool-truck...-camper-truck/

[nekkidhillbilly]

Originally Posted by andrewmp6

Nekkidhillbilly your way off on the front axles btw,Gm used 32 inch wide spring pads,79 back ford used 31.5 inch wide and 85-97 ford used 36.5.The leaf spring dodge is a 1/2 inch wider that make spring bushing adapters to use that but the leaf spring dodges are passenger drop.The 94 and newer dodge is drivers side but its a coil spring axle,Its a CAD axle and a unit bearing axle.Back to the OP either way you do its a monster of a job and a lot of money to pull this off.Can you weld and do you trust your life on your welding skill?Do you have the space to do this,Do you have the time?Your looking months maybe a year in the real world before youll have it driving.Like said a 12 valve cummins is a simpler swap because no ecu and wiring it like 6 wires.And they make swap parts to do this.If you do it either way start a build threat on here.

im aware the 79 back ford is the only one that will pretty much direct swap. to use any other left side drop will require welding on proper width perches. I thought I mentioned that. it was a long post sorry. yes the 94 up dodge is the only lhd ones and if I went to dodge I would get a 03 up hd one with the 9.25 aam I think. there is a conversion for them to go back to manual hubs also. also to add 98 up super duties are a different bolt pattern on the wheels so adapters or new hubs are needed if your keeping the chevy bolt pattern.

[nekkidhillbilly]

Originally Posted by andrewmp6

Have you seen project nightrain on trucks ?If https://www.powernationtv.com/episod...in-diesel-swap it is a 2wd 1/2 ton but the motor does fit with work.But having a 1 ton 4x4 you might get away with making a engine crossmember or notching it vs notching the oil pan like he did.For less a wiring headache http://www.btdieselworks.com/product...wiring-harness
For a intercooler you might get away with using a 1st gen powerstroke or 2nd gen cummins maybe.

I had long conv with the guy that owned the white one on youtube you see all the time. he actually used the 79 ford axle and the Allison dmax and tc off the new truck like I mentioned. its the only complete one ton ive seen. I think he had to build new cross members from scratch. but it all fit with the stock hood. it was a lb7 model dmax not the lbz. the earlier ford danas sell for about 2k at least.

[Dieselwrencher]

Nekkidhillbilly pretty much nailed it all. It can be done and has been done. It's really just how much you want to invest n the truck. If I had a Dmax and the time, I'd do it. The wiring harness can be built for very reasonable these days. I'd probably go with the K30 frame and the 79 Ford D60. I'm not big on the newer frames under old bodies. It just looks out of place IMO. And if you did decide to use a 94-02 dodge D60, forget about going with lock outs. What for? Peace of mind that the front end isn't spinning? I know guys that have done the swap on CTD trucks and didn't notice .5/mpg gains. Not worth it IMO. But if that's something you have to have, then go for it. Nice other builds too by the way.

[nekkidhillbilly]

yeah idk if the swap is worth it other than cheaper to upkeep somewhat but it cost 600 bucks for the swap.

[BK]

Thanks for all the input guys. I really dislike the look of lifted ifs, so I was leaning more toward swapping it all into a k30 frame which it looks like I may have scored. For the smoking deal I got on everything and how I can be world's ahead, I may be selling the duramax setup which could fund my whole chassis swap, lift, etc. I did have anther crazy idea with a 66 Chevy c60 cab and front end with a flatbed, but realized I don't need that many more rigs haha. We will see though, as the duramax gets dropped off tomorrow.

[nekkidhillbilly]

good luck I would love to have just a bone stock 78 k30 with a ls. wish I could find a deal on the crew you did.

[andrewmp6]

Whatever you do build start a build thread on here we'd love to see what you do.

[jwilson645]

I think 84chevyguy hit on the best solution above. Graft the 78 cab to the floor & firewall of the 06. A good buddy of mine used this process to sit a 66 Impala onto a Yukon Denali chassis. Now he has an AWD, 6.0L 66 Impala that he can tow his 1 ton Jeep with.

[nekkidhillbilly]

Originally Posted by jwilson645

I think 84chevyguy hit on the best solution above. Graft the 78 cab to the floor & firewall of the 06. A good buddy of mine used this process to sit a 66 Impala onto a Yukon Denali chassis. Now he has an AWD, 6.0L 66 Impala that he can tow his 1 ton Jeep with.

I honestly think that's a worse one in this case the solid axle k30 would be a much stronger set up. plus your going to have do things like weld custom body mounts, make custom bumper mounts, floor pan mods, custom fuel tank filler, the frame is going to need maybe shortened in certain places and lengthened in certain spots, figuring up the steering linkage, build a hybrid core support from the k30 and the new truck, and lastly you would have a lot more wiring. with the old truck can keep all the wiring and just add in the small amount you need to run the dmax ally and the tc. the tc would pretty much be a sesnor or 2 that should be in the engine/trans harness as long as use manual shift one. the only other thing is if you want to keep tapshift th and possibly the cruise. im not sure on cruise. anyhow you would need the bcm and basically 3 buttons or make a new shifter work. now to keep it where you can see the the dcim you just need to keep the cluster( you don't have to use the whole thing if you want a stock looking dash). just used the board from a cluster and desolder the display and run a ribbon cable to it so its mountable where ever you feel. hidden radio and mount it there would be nice. still anyway you look at it its a lot of work.

[BK]

Originally Posted by jwilson645

I think 84chevyguy hit on the best solution above. Graft the 78 cab to the floor & firewall of the 06. A good buddy of mine used this process to sit a 66 Impala onto a Yukon Denali chassis. Now he has an AWD, 6.0L 66 Impala that he can tow his 1 ton Jeep with.

I want to see this Impala!

I just made a deal where I got rid of an 04 denali, in trade for the full duramax truck, a front collision 02 avalanche with 5.3/rebuilt trans/transfer case, which I've already sold to a customer who I'm installing the setup into an FJ40, along with a 300k mile 6.0 out of a 2002 1500hd, as well as the 4l80e out of it. I'm already ahead money wise after just selling the 5.3 combo, and am thinking about rebuilding the 6.0 for my crew cab, or selling it and the 4l80e. Still lots of routes I can go at this time. Still weighing all my options. I'm not scared of work at all though.

[andrewmp6]

Your probably like a lot of us,Have a head full of ideas and builds but time and money makes us think harder if we should do it or not.

[BK]

Originally Posted by andrewmp6

Your probably like a lot of us,Have a head full of ideas and builds but time and money makes us think harder if we should do it or not.

Haha, I fight myself quite a bit. I'm trying to weigh all my options. I could potentially make a large profit by just selling the duramax chassis, as I'm more of an ls head anyway. I have plenty of time this winter as I only have two customer builds, so I'm sure I could pull it off. Oooohhh, choices haha.

[nekkidhillbilly]

money is my problem