47-55.1 AD Series Nasty Spots

[Father&son56project]

I am starting to consider my next build ( once I finish Project Fargolet), and up here in Ontario you have to start the hunt early as most of the stuff is rotten beyond words. I’ll be looking at unrestored trucks with a patina’d finish that I will leave alone. I’ve done 4 builds now, and I’m fairly decent at spotting rust problems, BUT every vehicle has its own unique problem spots and some of those spots can be truly miserable or expensive to repair. I like the AD series, and I will be checking out a ‘52 GMC shortbox in the future (it’s currently buried under snow), so I have a question for the forum members:

If you had to pick one or 2 spots where these trucks are prone to rust problems, and repairing these spots is truly awful, what would those spots be, and how would you examine the truck for those problems?

I can spot the usual suspects for rust, but a little input from members may keep me from discovering a true horror down the line!

[dsraven]

I think the biggest, most difficult to repair and get it right area on the AD trucks is the area just ahead of the doors on the A pillar. they rust out badly and it is the door pillar so that is what hangs the door, holds the firewall, connects to the floor and firewall, affects the fitment of the hood etc. if you don't get that right then it is all gonna be ill fitting from there on in. if that part is rusted then you can bet the floor is also partially rotten. next up would be the rear wall of the cab where the seam is. that repair is sometimes easier to replace the lower half of the rear wall from the middle of the rear window down as that leaves a smaller weld area than a full side to side weld. that would require a donor truck likely. the roof probably isn't much fun either due to the domed and tapered shape. I always advise guys to fit the doors as good as possible to the cab, then cross brace the door openings and the cab from side to side so it has to keep it's basic shape even if the firewall and floor is removed. that way if you start a repair and it gets deeper than you anticipated then the cab will still be "square" when you are done and the doors should still fit and close.
you could always buy a lotto ticket and hope. maybe you will win and could then afford a brand new cab........paint the patina if thats what you like.

[Father&son56project]

Thanks dsraven, that's exactly the sort of info I was looking for. Since I am in no rush, I will take my time and avoid trucks with those particular horrors. I've learned the value of avoiding rusty "bargains", and would rather pay a little more for a solid truck that won't cause me big headaches.

[Tempest67]

I agree with dsraven, cab corners, floors, lower doors, that is all manageable, but that rear cab wall seam would be a deal breaker for me. As with all these trucks, the lower A pillar/door hinge pockets are crucial for everything to 'fit' properly.

however, I have seen your metal working skills, and I think you would be able to overcome just about any rust repair.


Your truck is coming along great, can't wait to see it completed.

[dsraven]

an assembly manual is available for a reasonable price online and would show you exactly how stuff is assembled at the factory. it will show where the spot welds are and locations of any hidden brackets behind rear cab walls or roof corners etc. it also gives frame drawings with dimensions etc. it is a good source of info if you are unfamiliar with the new ruck you choose.
some cabs will have the little windows in the corners as well as the rear window. these may not be as straight and smooth as you would think once you get it home and start cleaning it up. especially if some kid has used the roof for a trampoline at some point or it was a work truck. the last AD I worked on was one like this and it took some time to get the side and rear window areas smooth for paint. one thing I have done when looking at different trucks or old cars for donors or projects is use something flat to run over the surfaces with, like a short sanding block with no sandpaper on it. you can identify the high spots quickly that way without wrecking the patina or whatever. sometimes the old chalky surfaces look really good until you get them wet or start working on them.
it may be a good idea to peruse the patch panels and full panels available from the suppliers. that gives you an idea of what is commonly rusted out on any particular unit you may be interested in pursuing. also an idea of what the repair costs can be should you be weighing out buying a pretty good unit for more money or a less good unit for less money. more money can be less in the end plus you are driving it sooner.
man, I wished somebody told me that long time ago...........oh well, my sheet metal skills got better, sort of........haha

[Father&son56project]

Thanks guys, I will definitely pay extra close attention to that rear seam. Working on the Fargolet has been liberating as I am leaving the dented, rust coated panels alone and I plan to do exactly the same with this next project. My last build (‘56 Chevy wagon) was a “bargain”, but it was really, really rotten and it took me 7 years to do (a mistake I won’t repeat). I have been perusing the online catalogues to see what patch panels are available, and also to see “what should be there”. Sometimes missing pieces are not that obvious (especially if it’s your first time doing a specific vehicle). I can spot a missing part on a ‘39-’47 Dodge/Fargo in a split second now, but that’s not the case for an AD truck. The LMC catalogue has decent exploded views that I will bring with me to ensure that everything is there (or if it’s missing, to ensure it can be purchased). I spent a half year searching for a door latch mechanism for the Fargolet, but if I had bought a Chev/GMC or Ford/Mercury I could have had one at my door in days, and at a reasonable price.

Thanks for the advice on what to watch for!

[mr48chev]

Dsraven pretty well nailed the big issues that are a hard fix.

I'm not a "patina" fan but have always looked for trucks that had original paint and as little rust as possible when looking for a project truck. Simply meaning less chance of hidden issues and you usually get what you see.

If you are planning a frame swap from the get go, don't pass up looking at big trucks with good cabs and little else going for them. You might even find one with a title that matches the door post tag and normally you can have the tonnage reduced down to 1/2 or 1/4 ton to pay minimum tonnage if you tell them you made a pickup out of it and it no longer hauls big loads.

[Father&son56project]

Mr48chev, I’m with you on finding something with original paint. When I see a vehicle that’s freshly painted or primered I start to worry. And if I see an underside that has been freshly sprayed with thick black goo, I walk away. Actually I run away as that is almost always done to conceal horrors. I live in an area of gravel roads, and an original patina covered truck is perfect for me (and I don’t have to do yet another body & paint job). As for using a big truck for just the body, I don’t plan on doing a frame swap this time. I had a ton of fun doing an S10 swap on the Fargolet, but one of the advantages of sticking to 47-55 Chev/Gm’s or 48-56 Ford/Merc’s is that upgrades are readily available (unlike for the Fargo). So I am stuck looking for pickups.

[fauXGT]

My '51 Montana farm truck cab (titled as a 6400 but on a 1/2 ton frame) had fairly shiny paint on the fire wall, but the rest was faded with rust creeping in and dents all over. The bad rust areas were the floor at the kick panels, the drivers side support below the lower door hinge, both outer lower skins between the doors and the front fenders and of course both lower rear cab corners.
My guess is these were built to hose out when filthy with the drain holes all over, but it lets the nasty from outside back in and rusts.

[edgeleycanuck]

In my opinion you may have better luck finding a one ton truck in acceptable condition vs. a 1/2 ton model. This seems to be the case in my province, there is still the odd rare one ton at farm auctions. I know you don't want to do a frame swap but I think you should be able to find a 1/2 ton chassis reasonable priced. The one ton as you probably know is the same body, it just has a longer box. Just some more food for thought in your search.

[dsraven]

if super serious about an AD for your next project you could get an assembly manual and that would give dimensional differences between the smaller and larger trucks. at some point the larger trucks will have a larger front end sheet metal package bolted onto the same sized cab as a half ton. there have been numerous guys who have purchased the big fendered trucks because of the good cab and then bought the required half ton donor that has the decent small fendred front sheet metal but the cab is pretty far gone to repair.