Projects Model AA Front Suspension

I have a 31 model AA truck that I'm excited about hotrodding. I'm looking for a parts list and what to do refresh and lower my front end using the stock frame (yes I have read its heavy, too much trouble filling holes, boxing etc..) and Z the rear. Most of the current suspension looks fairly worn out or too heavy duty. I've got a donor 302/C4 from a van and an 8.8 rear end with disks out of an Explorer. The more I read, the more I'm conflicted on what to do and what to buy, all I know is that I need a way to lower the front and rear end using as much of what I have as possible and feel like I need someone experienced to give me a play-by-play.

 

AA's have thicker spindles but the axles themselves are, I believe, the same as the cars.

You may not get much feedback on the modern rear end here, but you should not really need to "Z" anything to get it in there. Explore other options first. Z-ing a frame seems to have become such a buzz word that folks jump into projects thinking that's what they're supposed to do weather it is or not and can end up with a mess on their hands.

You need to figure out what your idea of the end result is. Figure out what wheels and tires you want; that will determine a lot as far as how far down you will want to go and how to get there. Also, fenders? No fenders? Full bed? Flat bed? Etc.

The thing you can do now though, is get a good set of later Ford passenger car spindles. The A axle will take them and you can put whatever brakes you want on them. Then get some roller wheels n hubs on them.

 

Also, the AA frame doesn't need boxing or filling or any of that. It's thicker and deeper than the car frames and will take a V8.

 

Get yourself a 37-40 axle dropped and have a reverse eye main leaf made to run it spring over. Either use some of your existing leaves or find another spring from a car and work with it. That is probably where I would start anyway.

The AA and BB chassis make good hot rod chassis yes they are heavy but they flex less and cost less as a rule.

 

'30-31 uses an entirely different axle from the '28-9, same as early BB. King pins are bigger than passenger but smaller than later trucks...no idea if ay later brakes or spindles might be easy to adapt. Later car front end would likely be best approach as already noted above. Seems like a good way to build an early pickup with modern levels of capacity!
It would be interesting to try using the AA rear spring setup (with a LOT of leaves deleted!). I think most people woud see it as super high-tech and clever!

 

The best way to hang your 8.8 is the same as hanging a 9, you buy the brackets and weld them to the rear end unless you decide to loose the buggy spring and go parallel leaves of coils of something.
Speedway sells the brackets and I am sure that someone of better reputation does as well. I prefer a spring behind the axle setup if I am not going with a parallel setup, but I am also inclined to go with coils if I am not using a buggy spring.

 

I did not know that, @Bruce Lancaster , thanks! Makes sense because the AA front axle I've got is all twisted up (must be 28/29). The spindles LOOK the same at a glance, but they are thicker for a bigger bearing to handle those big wheels.

@porknbeaner , AA rear ends are on outrigger parallel leaf setups. I think leaving the rear end setup as it is until the front end gets some attention is the best way to go. The front end is the easiest to work on with that big rig, so do all the fiddling up there til you're happy, then decide how to tackle the rear because everything going on back there is HEAVY. I think Bruce's idea of de-leaving the packs on the AA is a great one worth exploring.

@ludwiggler , can you post some pictures of the truck overall and some detail pictures of the rear suspension? There were a couple flavors, one of them is REALLY cool with an inverted leaf setup but I think that's early AA.

 

Change out the front cross-member to a Model A passenger car one as the truck ones drop down further. Then use a dropped Model A passenger car axle.

 

'28 AA spindles on an A axle were a common heavy duty upgrade for sprint car front ends, since the wheels on those also serve as bumpers...
AA rears had these really cool cantilever springs with shackles and pivots...use without a torque tube would I think require only a single ladder br down the middle, I think solid mounted beside differential, huge ball rod end at front...

 

My coupe has a AA frame under it. I like it.

I just took it thru Woburn Saturday nite...

 

While I agree with you on this, I don't think it's the FIRST thing to do. I'd try to find a stock Model A front end & spring to mock up under there first to get the mockup process going. Then I'd look into replacing the front crossmember, but I'd get one of the SoCal dropped 32 style front crossmembers and use that rather than trying to find a good A front crossmember, unless this is going to be a banger build.

Figuring out how much of a drop in the axle is desired after this point & knowing the wheel/tire combo, would be my plan.

@NoSurf , where were you rodding in Woburn?

 

Ya know I have seen those old frames and even seen pic of restored big truck and the fact that they had parallel leaves completely got away from me. I would definitely do away with the setup and either go with a cross leaf or coils if it were me but I am a goof ball.

 

Well, the AA setup is parallel leaves with the disadvantages removed. All the weight is carried on the chassis, not the axle and they serve almost purely as springs with little role in locating the axles. All attachments are swiveled or shackled. No disadvantages over a buggy spring, unlike hotchkiss style parallel leaves. And it is very cool and alien to a modern person...
Same general setup as many early Rolls Royces!

 

I will try to get some fresh pictures to post and try to ask advice as I go.

Do you think you've got a picture or two you'd be willing to share? I'm a visual guy just getting used to the terminology (I had to google "banger")

 

Thanks to everyone for comments. I will get home today and take some fresh photos and post them if there is any interest. Any suggestions for wheel/tire ideas?

 

The rear here looks like mine. So keeping those awesome springs is not an option... I most definitely want the disk brakes and the 8.8 rear end appeals to me because of its freeness.

 

So, I need to get rid of the AA stuff for mockup? Or just the spring?

 

Photos are a must for this crowd. We need to see what you've got to better answer your questions and come up with ideas.

Your W/T combo is going to be a matter of taste largely, but the HAMB is going to probably favor 16" wheels (steelies or wire) with Bias Ply tires. I'd say at least 600-16's on a truck if not 650's. If you want big n littles, maybe put some 700-16's in the back. Check out Coker Tire, their page has lots of pictures of their repop tires and, more importantly, their measurements.

Not necessarily. What really matters is the width of the rear end. If the rear end is the correct width or close enough, you can just cut the brackets off of the AA rear and weld them on to the 8.8 rear. You are going to have to weld stuff to that rear to mount springs and wishbones regardless. How wide is your rear end, flange to flange?

For the front end, put the thing on jack stands, pull out the AA front end.
If you can, leave the wishbone for now by removing the front perches and spring from the assembly.
Obtain a Model A or other 32 to 36 passenger front axle and reassemble with a passenger front spring and some 37-48 spindles (or 28-36 just for initial mockup).
Get some wheels with some hubs in them to roll it around.
You can use wooden blocks or cut plywood circles to simulate tire height.

 

I'm saying keeping the awesome springs is an option too! The setup could be adapted to any rear...the ends of the springs attach to a collar around the axle housing and pivot there so rear does not twist its position. Most likely the AA collars are for bigger diameter than late model rear, so could be bushed to whatever. Simple welded tabs on each side would prevent rear from sliding sideways. I think those springs would be VERY cool, and should be workable with about half the leaves tossed. All the help it would need geometrically would be a single bar filling the anti-twist role of the torque tube.
Main reason for tossing the front end is that we currently have NO clue as to what modern brakes would go on there how...and maybe that can be solved.

 

These are some pictures from a while ago and may be not specific to what you guys need to see but since I won't be home before dark, these will have to suffice for now.

 

THOSE ARE THE SPRINGS!

 

I have an AA frame to go under a T roadster project and I personally like the look of the frame, they're thick on the sides, not unlike a '32 frame but without the reveal line in it. And the frame horns are just as pretty as the passenger car frames in my opinion.

I don't know why he couldn't just flatten the front spring crossmember instead of replacing it. And me personally, my frame is cut off at the length of a passenger car frame (it was under a cut-down doodlebug farm truck at one time) and I would do the same to this one, and then weld a crossmember for a transverse spring onto the back, give it pickup truck proportions.

What I see above looks like a good start on a rod project to me, and I agree with Patmanta who says the frame does not need to be Z'd. Too many otherwise nice builds get ruined by an overly Z'd frame, in the name of super lowness, and it's unnecessary in my opinion. Plus, I can't even imagine cutting up that heavy bastard frame.

 

My 29 AA is set up with a '60 Rockwell rear axle from an F-350 tow truck. I added lower bars and "ears" on top of the axle to mount the end of the cantilever springs, which really are honkin' BIG! I want this truck to be high, not down in the weeds. Front axle is adapted to mount the F-350 spindles, brakes and wheels.

 

Someone on here was rocking a AA front axle on something, If I remember right they drilled the holy shit out of it and the bones, and also rebushed the ends for car spindles, but I might be wrong

 

I went down to GeneralGow's place where the coupe was hibernating for the winter.

Here's the pic of my coupe with AA frame in the April '14 issue of HotRod Magazine:



here is my crappy website that has a few build pics:
http://jdsweet33.tripod.com/

 

Here are a couple photos of my A chassis with a AA front crossmember in it. The 30-31 AA front is for a 2" wide spring not a 1-3/4". As far as I know it does not have a deeper step to the spring mount. I specifically chose it so I could run a complete dropped 40 axle unit I had laying around and give myself 6.5" more motor compartment without pushing my wheel base forward. It also let me run stock length frame horns.
The Wizzard

 

Here is a AA frame with a Blown Hemi and 4 speed coming together. No I'm not going to Box it. I just used a Model A passenger car rear cross member in it.
The Wizzard

 

What'd you do there, @Pist-n-Broke , locate the AA crossmember a bit forward and use F1 motor mounts?

 

AA crossmember is in stock A rivet holes so frame horns are of stock length forward. Yes those are F-1 motor mounts.
The Wizzard