1977 GMC CCDW build

[BigDooley77]

When I was 5 or 6 my dads friend had what I always thought was the greatest truck ever it was huge! Big! and tough looking sounded mean it was everything I thought a truck should be at the time an 80s all black GMC crew cab dually. Watching it in movies only made me want one more but I just never found one I wanted nor did I have the space. But in 2015 it found me I was working at a parts store talking to a customer about the truck I've always wanted when he says I have 2 of them I'll sell you one. We set up a time a friend and I went and looked at it was dusk when we rolled in the first truck in sight had a street light shining down on it was a 1976 Chevrolet Silverado Blue and white chrome horns on the roof it was beautiful it was straight but a bit rusty (which is fine). He comes out to greet us while we're looking this truck over. Finally he says the other one is down the hill so we head over my buddy in front of me I'm still oogling the Silverado behind me. Under a tree sits another crew cab dually its dark and the color isn't popping at all I get closer its a dark metallic gray and boy has this truck seen some action the fenders are covered in duct tape many trim pieces are missing but as I'm cresting the rear I notice the tailgate says GMC I yell at my buddy in excitement "dude this is a GMC!!" his response " I thought you noticed that". Now at this point you don't know me but GMC nameplate means a lot to me I know its not really special, but it is to me. So we get to talking about it he wants $1k for the gray 1977 GMC and $1200 for the 1976 Silverado I can only nudge him to $900. Let me tell you the truck is a heap its had a fire in the engine bay the rear tires are all in distress 2 completely blown out lol well I drove it home that night.

[Andler2008]

What're your plans for this thing?

[BigDooley77]

Originally Posted by Andler2008

What're your plans for this thing?

Plans are 22s, air bags, black and white paint scheme, and a 12v/4l80e combo. then pull a 41ft camper

[Andler2008]

Originally Posted by BigDooley77

Plans are 22s, air bags, black and white paint scheme, and a 12v/4l80e combo. then pull a 41ft camper

22's and bags. Nice. Got a specific setup for the front and rear suspension in mind? As in new A-Arms, 4 link, etc.

I like the idea of black/white paint and the cummins engine. If I knew anything about diesels and had the extra cash, I'd be going that route as well.

[BigDooley77]

I'm going to cup the front a arms and 4link the rear. here's how I see the 12v if I can learn how to build transmissions and engines I can learn the ins and outs of a Cummins. I'll make some mistakes I'm sure but I'll finally learn.

[Andler2008]

Originally Posted by BigDooley77

I'm going to cup the front a arms and 4link the rear. here's how I see the 12v if I can learn how to build transmissions and engine I can learn the ins and outs of a Cummins. I'll make some mistakes I'm sure but I'll finally learn.

Cool deal. We're in the same boat. I plan on using cups on the OEM arms and a 4 link on the rear as well with the bags over the axle.

That's typically how I look at everything lol I just get antsy and want to do more fab work than engine work.

[BigDooley77]

So some time goes by it only takes a few months before the 454 breathes its last breathe ugh sadly no oil pressure loud knocking then boom stops running I pull the motor replace it with a "good" used 454 I'm sure you know what happens next the second 454 doesn't last 3 months I park the old dually outta spite! now this is a truck I've always wanted so I'm not giving up! finally I drag it down to the shop an pull the engine and transmission out tear the engine down 7-8 rod bearings spun so it goes up to the local machine shop. While its out I start ripping into the interior I want bucket seats and a console the radio hasn't worked since I bought it the fuel tank selector didn't work the windshield was cracked from the fire and for some reason the column was completely destroyed (supposedly it got stolen once I don't believe it but what do you say). I start the dye process turning the vibrant red and white interior black. A local guy that parts these trucks out brought me some 89-91 bucket seats I talk to an aftermarket seat upholstery company after going a few rounds he will charge me more to make the rear seat since his kit comes with the 89-91 middle row for suburban. Well I call the local guy up and luckily he still has the middle row. Upholstery starts.

Added heated seats while I was at it

[BigDooley77]

some interior shots as worked to get it done over the winter.

[BigDooley77]

instead of replacing the column I just fixed it its was actually very easy still needed to do the windshield lol

[BigDooley77]

here's some shots of the engine, the machine shop update photo and the serpentine mock up. finally ready to stab it in for those that don't know the oil cooler mounts to the core support, there are 2 dimples that will need to be drilled out in order to bolt it in.

[BigDooley77]

I decided to go with electric fans so I pulled some from a 98-02 F-body ( v6 and v8 use the same fans in these years btw) some mock up before I used aluminum to make a bracket. riveted the fans to the bracket and made the bracket fit the factory fan shroud area.

got the engine back in wired the fans up with a generic Jegs kit plenty of room too I got o fire the truck up but its not right I really messed up ugh what could I have done... I fumbled around trying to diagnose the issue before finally deciding the timing is way off sadly I had placed the variable timing gear on the crankshaft wrong I was off 3 teeth I could explain this all day and some guys will just say dude its so simple yadda yadda don't wanna hear it lol fixed the issue new valves, new pushrods, and for safety new lifters. fired up timed the engine its purring like a kitten I had quite a bit done to the engine nothing crazy but I wanted as much torque as possible from the 454 and I wanted it cheap!. k1301 cam summit dual plane worked 781s.

[focusedontheprize]

Love it, I am in for the build.

Just picked up a '86 Chevrolet C30 CCDW with 26K original miles. I am going through it also at the moment.

[BigDooley77]

Originally Posted by focusedontheprize

Love it, I am in for the build.

Just picked up a '86 Chevrolet C30 CCDW with 26K original miles. I am going through it also at the moment.

I can't get enough of reading everyones builds if you do a thread let me know!

[BigDooley77]

so a small amount of time has gone by and the teeth on the flexplate are not doing well no matter what I do more shims less shims ugh keeps grinding well now the teeth are destroyed so I had to change the flexplate the th400 is dead in the way don't you know. so I changed the flexplate to a fancy 6 bolt one because I just picked up a 4l80e well what a perfect time to put it all in right before the monsoon here in Kansas. its in the truck now i rushed getting the controller i wish i would have researched just a little more i got a painless but really its a USShift which i don't mind... just that the USShift branded one was slightly cheaper... you live you learn. now i know guys are gonna say you could go Holley and have efi and a trans controller for not much more and i agree but that's if your staying with a gas engine my plan is to go 12v so i don't need the efi stuff, but i do need a controller. I dabble with LS engines and thought about just building one but after adding it all up i just didn't see the "cheapness" of building it these aftermarket systems come with really easy tuning software and so many cool options!.

so i built a bracket for the computer and put it in my center console outta sight but its easily accessible if i need to get to it. the 80e swap was fairly straight forward and the th400 trans mount fit the 4l80e. i added an HD2 kit and oversized the AFL valve piece of mind. I'm still finishing this part up.

[BigDooley77]

so here we are winter is almost here. I have just a few things left to complete for the swap. here some photos of what I have finished cooler line extensions, selector indicator, and TPS sensor bracket. I still need to build the linkage and finish drilling the frame the driveshaft is cut and ready for pick up hoping to get that Saturday.

[BigDooley77]

Here's some misc. photos, I upgraded the alternator and all the lighting. I'm also working on installing an aux battery to aid the system.

[OutlawDrifter]

I'll follow along, nice work so far! Someday I'd like to build a square dually for my shop.

[Dads79GMC]

Looks great!!

[BigDooley77]

Got a PM about the rear seat. The upper portion was a straight forward swap just set it in place hold the hinge fold it down drill holes screw the tapered bolts in. the Lower section I cut the legs down and welded them back to together this shortens the legs and allows you to fold the seat up. On the passenger side it doesn't do much except when the bottom is folded out the top can fold down further making it easier to reach the middle. The top portion will not fold down all the way since the hinge on the bottom will not allow enough travel. on the driver side I used the center support took some metal out and notched it now this side flipping up is nice it allows you to easily use the center area for storage I think I'm going to find or build a tray for that area.

[BigDooley77]

So last night I got down to the shop to work for awhile since the cable kit showed up finally. Found out how much the TPS bracket I made wasn't going to work lol so more cutting and some bending has everything working now. its too bad no one makes a cheap bracket for the QJet everything is $130-$150 on the market and I just don't have the funds lately. Still need to finish drilling the holes for the crossmember and finish up the linkage.

photo of the driveshaft Local shop needed the middle of the support bearing mount to the back of the transmission (37" with yoke in) then took out 1 inch boom 36" driveshaft with a new u-joint and slip yoke installed.

[BigDooley77]

Finished the linkage last night used a fellow members guide made short work of the task. Backed it out of the shop went around the block (quite a ways when you live in the middle of no where) it shifted flawlessly which just made my day! all the hard work is paying off finally. I still need to hook up the speedometer cable and Cable-X unit. I bought the unit used and the cable was cut so I need a new one. I also need to finish the tuning on the controller ( need to input the TPS information) assemble the last few pieces of the interior clean it all back up.

While on my drive I tested the seat heaters too wow that's a nice feature for an old truck! I will continue adding creature features my next project is adding Fog lights to a bumper I just picked up. I'm stuck on the switch I'm thinking about using the 89-91 suburban dash double switch fuel selector on one and the fog lights on the other then using the unused lighted section under the speedometer to have it illuminate Fog lamps when the switch is on.

I'm seriously thinking about adding power windows to the truck also.

[OutlawDrifter]

Any progress is a good thing!

[BigDooley77]

Unfortunately there was some issues with the trans of course... right.... buy used and the seller says its good its most likely junk. 3rd gear direct drive was toast its been a really cold winter so it took me some time to really get motivation by the time I felt like it we were in January. So I decided the best thing to do was send the transmission to a local guy its done now and back altos red eagle and kolenes to help strengthen it the rest of the hd2 kit installed (springs) along with new bushings etc. I should have it back in the truck this coming weekend then we can get back to the fun stuff.

[BigDooley77]

Transmission is back I didn't take a photo of it fully assembled but here's a photo of the case looking might darn pretty. I did get the transmission back in.

[BigDooley77]

So on Saturday we installed the trans hooked everything up filled it up backed the truck out whew that's one movement. I pull out of the driveway and then turn onto the main road, it seems like its going fine so I put my foot down a little to make sure it will down shift and it hesitates then does it. I pull off the road turn around to head back it starts really acting up like it can't move its own power. Starts feeling like its in neutral I start loosing momentum so I stop at the bottom of the hill before my road I give it a minute then proceed up the hill its holding first gear and creeping up the hill but I can't depress the pedal otherwise it starts revving up again finally I get it home and park it I did notice on the controller it read ErH now the manual doesn't decode this so I called the manufacturer today they don't know what that code means. I believe I have figured it out ErH Error Ratio High which doing some searching seems to narrow it down to pressure switch which is brand new or the VSS which is very old. since my controller doesn't use the input sensor I'm going to swap the sensors and see if that eliminates the issues. I really hope it does I miss driving this truck.

here's it running out in the cold night air right after I backed it out.