51 GMC 4x4
 

Hello everyone I'm new here and have seen so many cool trucks, I can't wait to get to do some more to mine.

I traded for this diamond in the ruff last spring. My plans are to make it my daily driver. It will be 4x4 have a 454 a nv4500 2wd tranny and a divorced np205 TC. I'll be running 12.50x35 tires 14 bolt rear and dana 44 front with 4.10 gears. I also plan on a gooseneck ball in the bed and stretching the bed about 10" to install a portable fuel tank.
Here is a few pics of how I found the truck.

Re: 51 GMC 4x4
 

Well I got it home and looked it over to see just what I had to work with. I thought it was a good start for all the mods I wanted to do. I really didn't have to worry about hurting anything as I went. lol

Re: 51 GMC 4x4
 

Looking forward to seeing your progress Axe. I'm thinking of an AD 4wd build myself. Good Luck, Rick

Re: 51 GMC 4x4
 

Well the fun begins. I have a s-10 blazer that I convert to straight axle, so that gives me a good parts store, axles, wiring harness, electric windows, etc. I wanted to use the original frame of the 51, so I started doing a little swapping and fitting.
As you can see in the 2nd pic the axle sets back to far, so I welded a piece of 3x3 tubing inside the frame to be able to move it forward.
The axle is a dana 44 out of a 85 j10, this axle works really good, the wms to wms on a 51 1/2 ton it 60" and a 3/4 ton is 62" and the dana is 62 1/2" so that keeps it close to the stock width. Also the pumpkin is a drives side drop so if you want to use a later model engine,trans and tc combo it will fit, and the original napco conversion for a 51 the pumpkin is drivers side drop, so it keeps that look if you want it.
You can see that the spring mounts are sticking pass the outside of the frame a good bit too.

Re: 51 GMC 4x4
 

Ok on to the rear axle.
In the first pic you can see where I extended the frame with the 3x3.
The rear was a bear, because of the frame width of these trucks and the running board mounts and the emergency cable mounts it was turning into a nightmare. Before anyone says that I could have used the original springs, I had no intentions of using them from the beginning, I wanted the ability to get lift springs and ride of later model springs is better, plus I'm going to a gooseneck ball in the bed. This truck going to be used and driven everyday, so I want to be able to get parts at any parts store and have some comforts of later models.

Re: 51 GMC 4x4
 

Welcome, this is a pretty cool project you have!

Re: 51 GMC 4x4
 

Time to start over.
After looking everything over I came to the conclusion that this was not working out like I wanted it to and I wasn't happy with the way it looked. So after a little measuring I decided to use a 66 long wheelbase frame that I had already converted to 4x4 earlier. So swapping the body over began. The springs and hangers on the 66 came off a 86 1ton I had. I will get some better pics of the springs and hangers on the 66 and do a little detail of how I did it in case someone else might want to do this too.
The last pic is the body just setting on the 66 frame.

Re: 51 GMC 4x4
 

Thanks Brett I know that I'm going into a lot of detail and hope no one gets bored, but looking at some of the other builds I noticed that no one explained how and why they did some things. I want people that want to build something, but are worried about their skill level see that it's not that bad and you don't have to run to a specialty store and buy high dollar stuff to do a build.

Axe

Re: 51 GMC 4x4
 

Nice project. I like the early 60s trucks.

Re: 51 GMC 4x4
 

Thanks JIMs70GMC I'm building a 66 with my son for him. I'll post it later as we get more done.
Axe

Re: 51 GMC 4x4
 

Converting a 66 2wd frame to 4x4.

First I removed all the 2wd suspension, then I cut the rivets out of the spring hangers on the 4x4 frame, mine was a 86 chevy single tire 1ton. Then I rolled the frontend under the 66 frame with the springs still bolted to the axle, I got the tires centered in the wheel well and found the front hanger sits under the core support mount. I centered the axle side to side and centered in wheel well, then clamped and bolted the front hanger in place. To get the back hanger distance let the frame down on the springs then mark where the center of the spring eye is. Mine came out right where the e-brake cable goes through the frame, so to over come this I heated the frame and took 2 BFH's and flattened out the frame on both side. There was 2 hole on each side of the frame and I reamed one of the holes out so that the rear spring hanger would just go through the frame, then drilled 4 holes and bolted it in. The front hanger will need a gusset welded on, you can see mine in the pic. That one is temporary until I get the rest of the 51 stuff mounted then I'll make one that looks better.

Re: 51 GMC 4x4
 

Back hangers.

I cut the rivets out of the spring hangers then roll the rear axle springs still bolted to axle. I marked the center of the wheel well then pulled the bed off to make things easier. When I got the axle centered, I found the rear hanger were the right width, but the front was a little too narrow. There is a couple of options, I could have cut the spring perches loose from the axle and moved the springs out, but I decided to trim some of the front hangers off. I trimmed off enough to slide a 3/8" plate between the frame and hanger then I welded the hanger to the plate and bolted everything to the frame. The back was straight forward, just get set clamp and drill, then bolt. Always use grade 8 bolts on any frame stuff. On both the front and rear axles, the front hangers have a lip that the frame sets on, make sure to drill and bolt this from the bottom

Re: 51 GMC 4x4
 

The other goodies.

The front crossmember fits in the frame, I did have to trim some off right above the motor mount, but was able to bolt it right in after that. I put a pic of a steering box I mounted on the frame. I marked the center of the bulge of the steering box on the frame, then I heated the frame and worked it to where the steering box mounts flush, so I wouldn't need to shim it out. Maybe this might help someone with build.

Re: 51 GMC 4x4
 

I would like ya'lls opinion, I'm thinking about adding 18 to 24" to the cab to make an extended cab. It will be awhiles before I get to that point, but I was wounding how that might look.

Re: 51 GMC 4x4
 

was the 66 frame originally a leaf spring or coil rear suspension?

Re: 51 GMC 4x4
 

The 66 was coil springs from the factory. My son and I are building him a 64 4x4, I set some 85 axles under it and it got me to thinking about building one with the original coil spring set up on rear. If you put the trailing arms on top of the axles you can run 35's, but he wants leaf spring on the rear for the ease of a smaller lift.
But that will be another project on down the road.

Re: 51 GMC 4x4
 

Thanks for posting this, Axe. This will help me with my project. How great that your son wants to build one with you! What memories he will have.

Re: 51 GMC 4x4
 

Randy I'll be more than happy to pass on any info that I have gathered.

Re: 51 GMC 4x4
 

Well since I got the body mounted it was time to address other issues. I didn't like that there wasn't any real structural support to the floor of the cab. So I made one. This also lets me buy slick plate to do it with. For what LMC wants for the 2 floor pieces, that leaves a 3/4" gap between them and only covers the front part of the floor board, I bought enough slick plate to do the whole floor and fix my bed too.
Well time for a little rust repair, all of this is straight forward, cut out the old put in the new.
I guess that has got me caught up to the present. I've had some health issues so I haven't been able to work on her, but I have been gathering parts. I traded for a nv4500 today and working on the trade for the 454. I also have my eye on a divorced np205, and I did trade for the rear cut off of a 1990 cab and chassis with a 14 bolt and good fuel tank. So maybe when I'm able to do some more to it I'll have a few pieces of the puzzle to work with.
I've been looking at the cab and it is calling for an 18" extension, can't wait to start on that. I hope everyone has good luck with their builds, and I'll post more as soon as I can. Remember your imagination is your only limitation.

Re: 51 GMC 4x4
 

Looking Good Axe, I just subscribed. Planning something similar. Rick

Re: 51 GMC 4x4
 

Sounds good Rick, make sure you post your build, we need more people to restore and keep these old trucks alive. The new ones just don't have character like these old trucks do. Good luck and have fun with your build.

Re: 51 GMC 4x4
 

I think what you are doing is awesome! That thing is gonna look super mean and cool with a gooseneck hanging off the back.