I purchased an Aerostar front end and will be installing it into my 56 F100.

I thought I would outline my plan and see if others who have done an Aerostar install see any problems. It can also serve as a possible guide for someone else if it turns out good.

My measurements show the stock frame to be 34.25 wide and the bottom of the Aerostar frame 36.25. I have seen various methods used to deal with the difference in width but I plan on slicing 2 inches out of the very center section and welding it back together. This will narrow the front by 2 inches and I think make the rest of the job easier.

Next it seems that the top of the Aerostar frame was wider than the bottom. The top was over 3.5 wide where the brackets mounted for the upper A-arm. I would like to make a spot 3.5 wide to mount these brackets using the original 3 long bolts on each side. The original IFS attached to the frame using 6 bolts. The bolts went through the upper brackets, through the frame and out the cross member behind the lower A-arm mounting points. If I use this same design then I know I will have the upper brackets in the right spot and it is simple. Another advantage of narrowing is to allow the bolts to be able to pass down through the frame. If I don't narrow then I have to add 1" outside the original fame. But the bolt holes would be coming down through the side of the frame, essentially cutting it in half. By narrowing the IFS crossmember I can use the original 6 bolt mounting scheme running through the original frame rails.

The height and width across the top of the frame will be increased by adding a 3.5 x 1 steel tube. 1" is needed to increase the height of the original frame to match the 5.25 height of the Aerostar frame. The outer edge of the tube will be flush with the outer edge of the frame. This will extend 1.25 beyond the inside of the frame (the original frame it 2.25 wide). I will then box this section of the frame by making a plate run from the inside bottom edge of this upper tube to the inside edge of the bottom frame. It will be at an angle, probably about 30 degrees. Instead of the steel tube I might just make this hole thing out of a couple of pieces of plate. The plate is only there to cover things up, I don't see any need for more strength in this area, the Aerostar cross beam is so heavey duty.

If I narrow the cross member then I need to adjust the rack and pinion. First I planned on keeping the R&P centered by cutting 1" of threads from each end and then screwing the ends on further. Instead I think it will get the steering lined up better and provide more engine clearance if I cut off 2" from the drivers side linkage. Then use the original mounting hole on the passenger side and drill a new hole on the drivers side 2 inches further out. I may have to rotate the rack to get the shaft at a better angle but I will keep it shifted to the drivers side by 2" instead of splitting the difference.

Any of you Aerostar pioneers see a flaw in my plan?

 

You are right about some of the bolts lining up with the edge of the frame.

I thought about using the original mounting scheme with bolts clamping the upper a-arm brackets through the frame and crossmember. Then I looked at that 4rth bolt on each side just bolting to the top of the Aerostar frame because it's outside of the crossmember and decidied that all 4 could just bolt through the new fabricated upper mounting plate.

The increase in track width at just 1 inch per side, can be taken care of by a 1 inch increase in backspace on the front rims so I have no plans to narrow the crossmember. I am going to notch the crossmember into the frame by 2 inches so I have to add a 3 inch spacing to the top of the frame. This structure will be fabricated to allow access to the 4 mounting bolts for the upper a-arm brackets. The notch will be contoured to the shape of the crossmember and the similarly contoured inner boxing plate will be extended above the frame the additional 3 inches to become part of the upper a-arm mounting structure. The holes in the crossmember for the mounting bolts provides the pattern for the positioning of the upper a-arm mounting bolts bolt fore-aft and lateral and the slop in these mounting holes plus the use of shims in the upper a-arm will allow sufficient adjustment range for camber and caster.

I am going to air bags so the shock towers are useless and already have been removed, the coil spring locators have been eliminated and the mounting holes have been filled in. I will weld the crossmember to the frame. The bags require an external shock mount which is an option even if you keep the coils and it gets rid of the ugly shock towers. I believe that the rack needs to be rotated although I recall seeing one install that kept the angle the same and used multiple flex joints to connect to the steering column. I will rotate the rack but keep its current centerline location. This will require notching the crossmember to clear the column connection.

My crossmember is ready to mount and the notch patern has been scribed on the side of the frame rail but that's as far as I have gotten.

Hope this provides some thoughts to get your creative juices flowing.

Regards, John

 

I read someplace that backspacing the wheels too much can be a problem because the wheel is already close to the upper part of the knuckle. I did not measure the clearance before taking things apart. Do you expect any problem in that area?

Also, does your upper A-arms have a vibration dampener weight attached to it (big hunk of metal)? I would like to remove mine because it looks ugly, any thoughts.

 

I would agree that too much backspace would be an issue especially with the upper ball, but an inch each side shouldn't be too bad. You could install some Aerostar rims and tires and see where that puts them in the wheel well. Then adjust from there.

I have mixed feeling about that glob. I'm going to clean mine up as best I can and then do an A B comparison. There must have been a good reason for them otherwise Ford would not have spent the money. It may be that the diameter and shape of the wire for the upper arm had a nasty resonance at some operating point.

Regards, John

 

I spent all weekend working on the installation. I am passed the 20 hour mark and still not finished. The suggested 20 hours in the IFS notes was probably a little optimistic considering you have to fab all your pieces yourself.

Friday night I realized that I had a clearance issue on my passenger side between the engine block and the cross member. I also realized at the same time that my engine is not mounted in the center of the engine compartment I was making all my plans based on what I measured on the drivers side. The only thing I worried about on the passenger side was the starter. Once I realized the engine was not centered I measured a few more times and found out that I would also have a clearance problem between the upper A-arm mounts and the blower on my engine. Most people won't have a blower mounted on the side of their engine but they could have exhaust headers in this area.

I had to rethink my whole aproach and realized that I could not narrow the front end. I needed the extra inch to move the A-arm bracket out over the fame more.

Now I am building the fame up one inch and out one inch for the upper A-arm brackets.

Another idea I am trying out is to cut a notch down into the Aerostar unit so that it fits up around the frame in the back section. Since the fame starts to get taller just behind the original axle centerline you have to do something to keep the Aerostar member levels. The pictures I have seen so far showed people have cut their frames to square it up so that it can rest on top of the aerostar unit. I don't like the idea of cutting the frame in this are, especially to make a sharp notch in the frame where my engine and the suspension mount. So, I decided to cut a notch down into the aerostar unit. Luckily you start the notch just behind where the coil spring sits.

If all goes well the rear of the frame will sit down inside the aerostar piece and I will weld where the two meet. Later if I want to remove the Aerostar I only have to cut the welds and clean it up with a little grinding action. The frame will still be in it's original shape.

I have taken pictures along the way and will post them once I get them sorted out.

Got to return the Plasma cutter I rented and then get some sleep

 

I put up some pictures from my weekend activities. There are a few things I didn't get a picture of, will have to go snap a few more.

I have written down all my measurements and dimensions of each piece so if it works out I can document what I did.

 

Looking good. I didn't recall the rack sitting up that high. I expect that the rear sump on my 5.0 will clear. Be careful how far down you move it because you don't want to screw up your steering geometry and get a bad case of bump steer. Looking forward to more pictures.

I wish I had a plasma cutter.

Regards, John

 

I rented the plasma cutter. Since the rental store isn't open on Sunday I could rent it Saturday morning and return it Monday morning and only pay for 1 day. I used it day and night to get my money's worth.

 

It appears that the centerline of the upper A-arm crossmember thing is stamped with the letter "C" and "K". The "C" seems to be the centerline of the drivers side and the "K" seems to indicate the centerline on the passengers side. Anybody else notice this?

 

"I spent all weekend working on the installation. I am passed the 20 hour mark and still not finished. The suggested 20 hours in the IFS notes was probably a little optimistic considering you have to fab all your pieces yourself."

Boilerbots

The IFS article was our best estimate for moderately skilled installer with a good assortment of tools. (i.e. if you are using a hacksaw where a cutting torch or plasma cutter is really needed, please take that into account.)

If several Aerostar guys decide the time is significantly inaccurate, I imagine we can get Kenny to edit it when he has time. We desire accuracy, but we also want to avoid hassling Kenny with constant minor changes.

 

Hi, I think I was the person that came up with the 20 hours to do the Aerostar install. It was based on having done a couple installs, and doing the same thing every time. It took many hours of planing, measureing, building templates and other things that were not in that 20 hr. time frame. I would like to do another install and make a video and templates to sell. I need to get mine on the road and make sure everything works properly before I do this. Ozzie

 

fenders,

Lol, it's never a hassle. I'd be more than happy to make as many changes as you want, as often as you wish.

Just shoot me an e-mail anytime.

 

I have just about every tool made except for the plasma cutter. I think the biggest error in time like Ozzie said it the time you spend measuring, planning and cutting out templates. Once you cut a piece with a template and a plasma cutter then it takes no time to cut another.

That is why I am saving my templates incase someone else could use them, I might be able to scan them and send them an image.

I am also TIG welding mine stuff which goes a little slower compared to MIG but I can make the weld nice and pretty looking.

I need to email Furgeson777 about the tech article. I think it needs to start off by defining the original F100 suspenion height and width since everything in the article is relative to this. My case is probably similiar to others where nothing on the truck is still in it's original condition so I don't know what a 3" drop is going to give me relative to what I have now.

I am doing the rack and pinion today.

 

Wow, lots of work and time has passed since I started but I got the crossmember welded in completely. The upper A-arm mounts are in and almost complete.

The rack and pinion is installed.

I had to heavily modify my oil pan, remember my engine is very tall so it is sitting pretty deap between the frame rails. Then I had to modify the oil sump. I basically turned my pan around 180 and then made it a rear sump pan. I hope it holds enough oil, I might have to go back and make the pan wider in the rear to hold more oil. It took a lot of time to do this with the engine in the truck because I had to lift the engine about 4 inches to get the pan in and out. Then I had to lower the engine to make sure things would clear. I did all this with 2 floor jacks.

I replaced the upper and lower ball joints on the A-arms. I had to make a piece on my lathe to be able to press the lower ball joints into the A-arms.

I am going to install a hydroboost brake system. I purchased all the parts from someone parting out an 84 Chevy C20 Suburban that had the 6.2 GM (Detroit Diesel) engine. The power steering pump is a big Saginaw with a remote resevoir so that should work nice. Since the pump was designed for a hydroboost system it has two tank returns which I need.

Anyway the clock is ticking, I got a notice from the City of San Jose that I am in violation of a code because I have a dismantled vehicle in my driveway. I really got to get my truck moving now.

 

Has anyone finished their's? I lack plumbing my break lines and installing the 289 back in. I found that you have to replace the 289 oil pan with the double sump pan off a newer 5.0 (the hard way). I've also found that a set of 15's with a 4" back space will work and clear the upper A-arms. Oh, and that 20 hour thing HA,HA. i took a week off work to get it done and i'm still not done. Thanks to all of ya'll insight I'm this far. it looks good and I think it will be a great improvement on the ride and stability of the truck. Thanks for all of ya'lls help, I'm in the home stretch.