Trusty Rusty - 72 GMC LWB

[KY_GMC]

Today we started the tear down of Trusty Rusty.

We are starting with a 1972 GMC Super Custom LWB. It has a 350 SBC and TH350 with a 12 bolt rear end. The truck was originally from Arizona and the PO purchased it and drove it back to Cincinnati, OH. I have owned it since 1998. This truck came with power steering, brakes and the heavy duty front and rear springs and can haul a load!

Our plan is to remove the 350 and stroke it into a 383. With GMPP Vortec heads, Comp Cams 268 and headers, we should be able to get around 400HP.

The front end will be rebuilt, frame painted and plenty of body work. I am going to stay with the stock colors with exception of adding the two tone while stripe on the sides.

I would like to get a 4/6 drop on this truck, not sure if I can find some leaf springs that will be able to get this drop and still be able to haul a decent load. We'll see.

Here is what we are starting with.











More to follow.

[KY_GMC]

And here is what it looks like after the first day.

Now the engine tear down begins.





While the engine is off at the machine shop, we will start with tear off the front clip and start working on the replacing the front suspension.

[MoFormula]

[IMG][/IMG]

Great. My son and I started the same project last month, 1972 GMC Sierra Grande. Can't wait to see what you do. Much to learn on my end.

[MoFormula]

Sorry, duplicate post.

[MoFormula]

Any updates?

[KY_GMC]

Well, it has been a while since the last update. Sorry. There has been some progress, just haven't posted it yet.

So, here it is.

We got the front clip removed and noticed that the front frame horns are bent

Its kind of hard to see, but the right front horn is going to the left and the core support bracket is bent back. The left horn is also going to the left, but not as much. Looking for a good frame shop that can get this frame back into shape.
That was a depressing day!

Last weekend we got the bed off the truck. Not too hard with just the two of us and an engine hoist



Not bad for a days work.

[KY_GMC]

We've been working on getting everything out of the cab the past week. Luckily, my son has been helping while I have been traveling for work. He got a lot done without me!

We found rust damage in both sides of the front floors. The drivers side inner and outer rocker need to be replaced as well as the cab support. The passenger side floor and rocker will need to be replaced also. May do the cab support as well while we are at it.







This will be our first attempt at replacing body panels. We will have some help from some expert welders though.

[KY_GMC]

One thing that I knew all along was that this truck had a heavy duty rear suspension. But after removing the bed, you can see just how heavy duty it is! It's going to be interesting getting a 6" drop with this setup!


Not sure what happened here, but it looks like the rear horns on the frame were replaced with some c-channel.

[MoFormula]

Interesting, I found out my front frame horns were bent also. Just got it back from the frame shop with my front bumper installed.

[KY_GMC]

Originally Posted by MoFormula

Interesting, I found out my front frame horns were bent also. Just got it back from the frame shop with my front bumper installed.

Yeah, I guess after 41 years of being on the road that some damage is bound to happen.

What did it take to get it straightened?
Did you have the body on the frame or not?

I've checked around and one guy wanted the body on the frame in order to insure that everything lines up. I'm skeptical of that method since I already have it apart and the body mounts are shot anyway. I'm trying to find someone who will straighten it from the specs on the frame alone.

[rhm63]

[QUOTE=We got the front clip removed and noticed that the front frame horns are bent [/QUOTE]

Mine has the same issue, slightly less though. I will be following along.

[KY_GMC]

After taking of the bed and cab, we noticed that the frame rail on the passenger side is an "S" shape and the driver side is a slight "C". It's a little worse than originally expected. Starting underneath the cab and going forward, it bows outward and then it curves back inward at the front suspension cross member and then curves back out at the frame horns.

We made some crude measurements and it is definitely racked, but the wheel base is equal on both sides. Still trying to figure out what needs to be corrected to get it back close to square.

Talked to a lot of frame shops in the area and they all want to see the truck with the body on it so that they can straighten the frame to the panels. Going to check out a place this week to see if they will straighten it to the specs. This has sure slowed things down a bit. And on top of that, I have to travel to Germany for two weeks. Not a whole lot is going to get done for a while.

On the bright side, got the block back from the machine shop and they did not have to clearance for the stroker crank and rods, which saved me $300! So at least we can work on building the 383.

[MoFormula]

Mine was not that bad. We have a frame shop here in town that pulled both frame horns back in spec. My truck had the body on and he wanted my bumper too. After he had the frame close, he mounted the bumper and tweaked the frame so that the bumper was evenly spaced between the front fenders.

[KY_GMC]

Well, it has been some time since the last post and we have made some progress. We have torn down everything from the frame. Using the sand blaster at work and wire wheeling the all of the big stuff. We tried to find a sand blaster that would do the work at a reasonable price (under $500!), so we decided to wire wheel everything. After two weeks of throwing dust around the garage, I will work harder to find a sand blaster! While the results turned out pretty good, it took a lot to get it done.

This is prior to painting.

[KY_GMC]

I decided to go with the Master Coat Series paint for the frame. It takes a lot of steps to complete, but I think that it will be worth it. After cleaning the frame, the metal prep and rust remover is sprayed on the frame and then scrubbed with scotch brite until all of the rust is dissolved. Even after wire brushing, there was still some rust on the surface and this stuff neutralized it. Then the next step was to apply the first primer coat with the Permanent Rust Sealer. There is aluminum flake in it that helps to achieve an air barrier to the metal to prevent rust from starting again.

The kit came with one quart of primer and one quart of paint. But there was not enough primer for two coats We were only able to get one coat with a little leftover. It is recommended to spray the coatings and this worked pretty well with an old siphon paint sprayer. This should have extended the application since we were not brushing it on, but we still came up short. Once we got the gun set up, it seemed to lay the paint pretty good. We were happy with the results.

See for yourself:











Once more primer gets here, we'll shoot a second coat and then move on to the final top coat of the AG111. This is a two part urethane that is supposed to be more durable than POR15 and KBS and is also UV stable.

[KY_GMC]

Finally got the frame painted. Getting the final of three coats applied feels good. Now we wait for the front end parts from RockAuto, spindles and springs from ECE and flip kit from DJM. It will be nice to get this thing rolling again.









After we get this back on wheels, we'll start in on the body work. Still need to decide if we should rebuild the TH350 or source a 700R4. If we go with the 700R4, then we can put a 3.73 gear in the rear end. Otherwise, I was thinking of running a 3.43 with the TH350. I want this to be highway friendly so that it we can drive it long distances without running close to 3000 RPM.

[KY_GMC]

WOW! It's been a while since we've updated! Here's what we've been up to:

Firstly, we rebuilt the front suspension with quality MOOG replacement parts, and got rebuilt brake calipers for the front, replaced the disks, put in some new pads, ran new brake lines, installed drop spindles and springs, a very thick front swaybar from a squarebody c30, and then looked at how pretty it all looked!





Then, we started on the finishing products on the engine, including sanding down and repainting the fan, installing the waterpump, the alternator, intake manifold, and a performance HEI (not pictured).



We then rebuilt the rear end, replacing all the bearings inside of it, shimmed all the gears, replaced the axles, installed a limited slip diff, and then put it all back under the frame along with an axle flip kit. Later on, we replaced ALL the brake components on the rear end.



Lastly, we received our new "rear-mount" tank, trimmed it to fit, and then installed it!

[KY_GMC]

The last post was all done up till about mid February of 2014, this post will be late February onward.

We started to rebuild the transmission. Ordered all the components we needed, had the parts machined to add an extra friction and steel to firm up the 1-2 shift, pressure tested it, and then put it back together. Heres the before-after.




Then we had the driveshaft rebuilt and balanced at Cincinnati Driveshaft. Great guys, quick turn around, and great pricing!



Then we mated the engine and trans...



And sent it home

[KY_GMC]

After we felt that the chassis was buttoned up, we moved onto the body, doing some rust and dent repair, including the rockers and floors, filling a hole in the firewall, and filling the fuel filler hole, as well as starting to straighten the totally warped cab rear.







Then we sent the whole body off to be acid dipped.



In the mean time, my son got this shot of a great short bed at a local cruise-in.

[KY_GMC]

In between the last post and now is a large gap where no pictures seem to have been taken. We got the truck back from the acid dipper and found much more damage than previously assumed. So we got to work. We started by priming everything, since it was all bare metal. Then, recently, we started bondo work on the bed. That brings us up to today.

The truck was rear ended at some point, as shown on the two rear lower panels on the bed, so we got to work on those today.
Heres the panel beforehand, and our outlined where we cut them.



No photos of the process, but here's the after once my son welded the new panel that we cut and shaped in.





And here's some photos of the filler work on the bed:

[KY_GMC]

So, it has been a while since the last post, and we have been making some progress. Took the bed completely apart and replaced the rear 15" portion of the bed floor. Along with filling in numerous holes in the floor upfront. Purchased a new front section from Fix My Rust. They had free shipping in November that I should have taking advantage of for more parts.

After many weeks of welding, and body putty, both sides are straight, the wheel arches are filled and straight and bed is back together.

We had to also remove the bed floor brace to clear the relocated gas tank.

With the bed in pieces, it was easier to build the bed on the truck a piece at a time. We had a nice day in January and rolled the chassis out on the driveway and made some progress. We also completed the fuel line install before the bed went on.

[KY_GMC]

With the bed on, we are liking the stance so far. Using the DJM flip kit on the rear springs.




With the bed on, we are concerned about how to connect the fuel filler to the tank with the little clearance that remains. Does anyone have any suggestions on the best way to make this connection? I am planning on doing the filler behind the tail light mod.

[trac209]

Nice work!!

[lokivegas]

awesome build! im currently building a 1969 gmc LWB. have done 5lug disc swap with drop spindles on front with springs, and used a '71 gmc rear end/leaf springs for rear 5lug swap. also installed a djm flip and as of now my rear end is sitting about 3" or so higher than ffront so i need to look into blocks or shackles i think. got my "blazer" tank mocked up last night, and i am routing filler up behind side marker light.

[lokivegas]

heres my truck, or as it sits now.. and picture of how i will route my filler tube from tank. picture is from a friend who did his up through stake pocket. only thing different will be mine will go out straight towards bedside farther before turning towards back of truck so i miss the shackles.