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106 Posts
Discussion Starter · #1 ·
I decided to do a separate thread for this. I think a few people will be interested in this. Since the front steering set up on our vans is well...weak to say the least.

I am doing a lot of changes to my van at the moment. The background on it is I have a AWD 95 lifted and 31's as well as a 5.3l conversion I did about 6 years ago. Van has been great but the 95 body has finally had the biscuit. It has rotted out where it mounts to the frame and the drivers side was 1.5" lower than the passenger side. The body has about 475,000 km on it so im not surprised its done considering the salt we have here in Alberta and the countless off road trips I have done with it.

So it was time for a new body, I found a nice 2000 RWD as the donor. And so at the same time I wanted to tackle the list of improvements that I have made over the last 6 years and 100,000 km of driving the van. I will dedicate this post to the rack and pinion mod, but here is a list of the other things I had on my list, I will post links to them as I make other threads regarding these mods for those who are interested in the other stuff.

1. Convert to rack and pinion.
2. Replace Body 95 awd to 2000 RWD body.
3. Build sub frame connectors And Do the body lift properly ( welded spacers on frame) viewtopic.php?f=127&t=91113&p=882777#p882777
4. Install some electronics / Deck with rear view camera/ Marine Charger for 3 batteriaes / External plug for 15A 110v for gen set or camping spot/ Roof rack spot lights with remote/ LED roof rack tail lights ECT ECT.

Before I start my rack rant I need your help. I need the pin out for a couple connectors on the 2000 Astro donor body. I cant seem to find the info or even the name of the big firewall connector. Please go here and help me out if you can. viewtopic.php?f=76&t=91057
Here are the pics of the connectoer I need help with.

And this one as well


I have not seen anyone do a AWD Rack And Pinion Conversion yet. However I did see someone do a RWD using a Mustang rack somewhere on here. From what I read they did not take the geometry of the steering into consideration, and the vans had weird steering and bump steer issues.

I'm familiar with the Ackerman steering geometry theory as well as bump steer. So I thought id try my hand at doing a AWD conversion and try to get the geometry close and the van to drive normally. This is important to me as I do a lot of trips with it. So here is what I came up with.

I had a Mustang rack from my brothers car and quickly found out that even though the inner tie rod joints were almost exactly the distance of the Astro inner joints the rack could not be placed in the proper spot to avoid the bump steer and to get the Ackerman angles right. The Front diff as well as the diff mounts are simply in the way. The other issue was if it was placed in the right spot somehow the steering shaft comes out right under the PS pump. Other problems included the mounts being in totally the wrong spot as well as the steering shaft would almost have to go backwards from the fire wall or two shafts would need to be made and with a intermediate bearing and shaft to tie it all together.

So I went on a search of the internet and junk yards for something that would make sense. I had a idea in my head it was just a matter of finding the right donor rack. Well I found one, it is from a 2005 F150 4x4. I got it from the junk yard for $35 and its in great shape.

On the truck it is bolted to the front of the frame where I thought would be a the perfect spot for the Astro as well.The Ford f150 Rack is very heavy duty compared to the Mustang unit, and it has 6.5" of travel VS the 6" of the Mustang which is barely enough for the Astro. Also the bonus is the tie rod ends can also be used and are almost twice the size of the Astros.

The rack is very big and long so to make all the geometry work I knew i would have to make a bar which would attach the tie rod ends in the positions they needed to be. I seen this on some Hot Rod conversion rack kits out there so that's where I got the idea. Those racks are $1500 to $2500 however. And probably more for a custom one made for a Astro project.

Anyway here is some pics of the progression of the build.
First I measured the angles of the stock tie rods. They are angled back from 90 deg. That is the Akerman steering. They are also angled the same angle as the A arms for bump steer.
Here is the first mock up after removing all stock components including the steering box. The Rack is just sitting there on some jack stands. I can see a coule of issues but it looks like it will work.
This is my basic idea, I was going to make a shaft attacjed to the rack. And have the tie rods attached to that shaft in the locations they needed to be for the geometry to be right. And this way I could always change the mounting points.

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106 Posts
Discussion Starter · #3 ·
Ok so im a lot further ahead on this than my posts. I started this mod a few weeks ago but im trying to go step by step here so that I give you guys all the info I can. Im not finished the mod yet and wont be able to drive the van for a while yet. So I will keep updating this post as time allows.

Ok so once I removed the stock steering components including the steering box I was able to place the rack into position to do a quick mock up.
Just to see if it would even remotely work and if I could get the tie rods mounted in the proper positions. I took a lot of time to get the position right. Here it is just sitting on a couple of jack stands. Basically centered and in the exact spot where it would have to be mounted.

As you can see there is two problems visible in the above pic. One is that on the drivers side the rack gear preload cap and nut hit the lower A arm mount on the frame. And on the other side the rack mount hits the passenger side A arm mount. So I marked the position of the cap VS the rack body, removed the lock nut, cap and spring inside. I cut a rubber cap and placed it inside to keep filings out, then machined 1/4 off the boss.

I also then machined the cap on the lathe the same 1/4".

Reassembled it back to the position of the marks I made on the cap to have the same preload. Here it is all put together and 1/4" shorter.

This is the only mods I had to do to the rack, and between the milling and lathe it was only 45min to do start to finish.

To tackle problem two on the passenger side I trimmed off some of the mount on that side of the rack. I also had to grind a oval hole in the A arm mount on the passenger side. A small portion of the rack mount to protrudes into this hole and into the A arm mount. But it does not get in the way of the lower A arm at all I checked through the full travel of the A arm. Here is the trimmed mount on one side, normally its square.

Now I was really able to line up the rack nicely where I thought it should be and square it up on my jack stands. Just used some shims and whatever worked to do that. At this point I was quite confident this would work, so it was time to make some mounts and tack them into place.
That way I could mock up the rest of it and actually have the rack secured to the frame. and if things didn't work out I could always cut the tack and get it all off and return to stock steering components. I started to make some mounts from 1/4" steel and bent them in my press to get the rack in the right position and at the right angle. And level to the frame of course.

ONE THING HERE IS UBER IMPORTANT. Because the rack is long and it will have a bar and spacers for the boots attached to the ends of it, if the rack is not placed correctly it is possible the lower A arm will hit it when the suspension is compressed all the way, and the wheel is turned outwards. I made sure I had my torsion bars and shocks out and the lower A arms all the way up against the stoppers when making the mounts.

Now that I had the rack attached to the frame I could go to the next step. Making spacers for the end boots. Only after that I could make the cross bar. I decided I needed aprox 2.100" spacers on each end. They are necessary because otherwise the rack gear and shaft will be exposed to the elements. And I needed the 2.1" spacers for the boots to have space once compressed. First I tried trimming the stock boots down and using them. But I found the rubber is much to stiff. And they don't like to stretch from 2.1" compressed out to 8.5" (6.5" of rack travel plus the 2.1 of spacer). I mean I think they would work but they were really getting stretched hard. Here are the first spacers I made. They are made to be a travel stopper as well as mounts for the trimmed OEM ford boot

At least the small ends of the stock boots worked for making the inner tie rod end boots.

Now that I had the spacers I could finally make the cross bar. A buddy of mine is a machinist. And is certified to actually make steering components, so I relied on him for some of the critical knowledge. Like what steel to use and how to bend it, turns out its just mild steel hot bent. And also we both agreed that there should be no welds on any steering parts. So that changed my design a bit from the drawing I posted earlier.
Here we are in his shop bending a 1.5" x 0.5" thick peace of flat bar for the cross bar. We used a torch and a combination of a jig in his press ( basically two peaces of angle iron) as well as some hand bending in a vice.

I decided on the flat bar and not something else like round bar ect for a few reasons, one attachment of the bar to the rack, second attachment
of the tie rod brackets. And also I just did not have the room for round between the rack gear housing and the bar. And it would place my tie rod ends to far back. Here is the first mock up of the cross bar on the rack with the boot spacers.

And the first mock up of the attachment points for the tie rod ends. The joints are the exact distance apart as the OEM .
I machined the cross bar where the tie rod brackets would be located. These will be bolted on (remember no welding allowed) so these slots will positively locate them once bolted. I only went 0.100" depth.

The actual rod brackets are made from 1/2' thick 3" angle iron and trimmed to suit. These ones are just mock up ones.

Ok now I was finally able to get it back on the frame, and figure out the position of the inner tie rod on the bracket. This is where all my measurements of the OEM position came into play. Once I got it I figured I drilled a hole and mounted them to the temporary brackets.

Then came the point of no return, but I am feeling confident. In order to see how everything works I had to ream out my spindles to accept the ford outer tie rods. I had to buy a reamer for $150. Ouch! It is a 1.5" per foot reamer BTW. I'm sure it will be worth it because they are nice and big compared with the astros.


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106 Posts
Discussion Starter · #6 ·
After the ream job :lol: I was able to get it all assembled and do a quick alignment to try and see how everything moved. It all seems to clear nicely and the steering tops out on the spindle stoppers against the a arms. Which is what I wanted. I did not want to limit my turning radius with this mod. The rack seems to have about 1/4' of travel left on each side when at max turn left or right. This is perfect for alignment purposes too.
Here it is basically all mocked up with the F150 outer tie rod end installed. :dance:
Now I can start to build all the proper brackets. I also tried the sway bar and it clears everything, so I decided its time to commit 100%. Make the matching lower rack mounts and weld them to the frame.

I made proper inner tie rod mounting brackets. I had to get a 16x1.5 tap just to do these two brackets. $30 at Fastenal FYI. They will thread into the brackets and have a jam nut on the other side.
Next came the problem of the boots. It just so happens I have rancho 9000 shocks on the van. And I removed one of the boots because it looked like it might work for this. They are super soft and very stretchy unlike the OEM ford ones. So I got some off Amazon for $10 each. PN / RS 1952.
I had to modify the ends of the spacers I made earlier for the new boots, and trim the boots to length, they worked out beautifully. :thumbup:

The next thing I decided to do is add another peace of flat bar to the middle of the cross bar to strengthen it. I run 31" tires and hit the trails and rough roads on my trips so some extra strength is always a plus. It is 1/2 thick by 1 1/4" wide bolted on with 3/8 counter sunk bolts. Nice tight fit between the tie rod brackets. It is 1/4 less in width than the main bar because I needed the extra clearance on the oil pan of the 5.3l engine.
here is where the biggest clearance issue is on the rack, I filed a bit off the rack shaft housing and machined down the heads by 0.150" on the two bracket bolts that move past it. I wanted to get close to 1/4 of clearance between them.
I used two 1/2 NF bolts and pinned castle nuts to secure the tie rod brackets on each side. I had to drill the bolts. I must be getting confident, started painting the parts :D

Here is how it looks beside the mess of stock components I will be going from 10 moving joints to just 4. And the 4 are going to be twice the size of the original Astro stuff.

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1,305 Posts
Wow, I'm impressed... I never would have even thought to ask the question.... Great work!

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1989 Astro RS on a 1998 AWD frame with a 1994 350 TBI
7,391 Posts
Great work , now I have some questions, first what is the advantage to rack and pinion over conventional steering? ( I have never driven a vehicle with rack to my knowledge) and is this something that could be built in kit form and sold? would it be much difference to do on a rear drive van? I read the previous attempts and they had problems but have not posted if they fixed the problems. Thanks Mark

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106 Posts
Discussion Starter · #10 ·
WoodButcher said:
Beautiful work.
You have the body off, would this be doable you think w/ body on?
Yes I think it would be, may be a bit more difficult to get the rack positioned and mounts welded in. But if the front end was off and rads out I think it would not be too bad to do

markmitch said:
Great work , now I have some questions, first what is the advantage to rack and pinion over conventional steering? ( I have never driven a vehicle with rack to my knowledge) and is this something that could be built in kit form and sold? would it be much difference to do on a rear drive van? I read the previous attempts and they had problems but have not posted if they fixed the problems. Thanks Mark

The problems came from using a rack that roughly fit and putting it in the wrong position. Throwing off the steering geometry. There is a bit to it with all the angles and working geometry. So you cant just bolt something it , hook up your tie rods and call it good. There are many articles on the net about steering geometry and what it does. To start with its best to try to recreate the stock angles and work from there. There are many benefits to rack and pinion as mentioned above for one you now have 4 wear points instead of 10. Each one of those points gets a bit of wear and you have sloop in your steering and the van drives like crap. These vans are notorious for wearing out the front end parts. That leads to tire wear and sloppy handling. Really tires you out on long trips or on icy roads. Most people have to replace the front end components often on Astro$$$. The rack gives much better feel and response. And its cheaper to replace $300-$400 for a rebuild one. And I spent over $1100 last year replacing all the stock steering parts you see above with moog parts. And that didn't even include the steering box, which would have ben another $600.

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3,000 Posts
Yes, the dreaded curse of AWD steering. I've dealt with sloppy steering in my van since I've owned it ( 5+ years ) and have replaced all the ball joints, idler arms, steering gearbox and have constantly made sure to keep things lubed up. I'm to the point of wanting to replace the drag bar and tie rod ends, along with the A arm bushings. Driving on ice is scary in this confidence to drive over 40mph if the road is slick because it feels like it would take near anything to throw me off the road. I love the rack and pinion steering in our Sport trac and our old Santa Fe. I didn't think it would be possible to do this mod to the AWD van. Keep it up, I'm rooting for you! I will never do it myself because I don't have the tools or place to do the work...but I'd sure love to have this set up...might make me like my van again.

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2,784 Posts
Looks good so far, I've been wanting to do this to my van, and have been gathering data about it. I've seen r&p setups like what you're doing, and I know you're still working on it, but my question is what is keeping the bar from rotating around the mounting points on the rack?


The circled part in the pic on this aftermarket r&p keeps it from rotating. This is what has kept me from doing it this way so far, I haven't thought of a good solution.

I do like your mod so far.


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3,000 Posts
I actually was thinking the same thing, but figured there was something in the works. Doesn't seem like that's designed to worry about too much lateral pressure, and the rack design doesn't require anything originally to deal with up and down motion from the tie rods, though it would be at a fixed point in the rack. That point of contact in the picture really looks just to keep the bar stable, to avoid excess movement...I wonder how much movement there actually is since the bar he made is beefed up to keep it from contorting.

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106 Posts
Discussion Starter · #14 ·
You bet guys, Having something to stabilize the bar is something that has to be there. If for any reason the bolts on the end come loose or there is enough force pushing on the tie rods and the bar then the bar could possibly shift up or down. This has always been part of it for me and ya its been in the works. I basically got my idea for this from the same rack you posted above Andrew. So in the last couple of weeks or so I've measured everything up and designed some clamps as well as a plate that will house 4 bearings that the bar will ride on. I ordered the bearings, plate and clams up and just got it all a few days ago. I don't like the idea of the aftermarket rack above, as it looks like it just has bolt heads or small plastic bushings there to keep the bar in place. I wanted my design to be beafy and stand up to whatever I throw at it miles wise and while 4x4ing.
So here is my design.
Rack clamps and bearing plate Assembly view 2.JPG
Rack clamps and bearing plateAssembly 1.JPG

I had the plate laser cut from 1/4 steel and the clamps water jet cut from 1" aluminum. The bearings are 6300 RS. I ordered all stainless bolts and nuts for this as I want it come apart easily in a few years and they will not be under that much stress anyway so SS will do. On everything else I either used factory or 10.9 or 8.8 grade bolts. Here are some of the parts after cutting.

I got it all mocked up here. Keep in mind I don't yet have the fasteners I ordered for this, they should be in any day now. So I just used bolts I had laying around to mock it up. Turns out I got the spacing of the bearings perfect and they house the bar between them nice and snug. And it works very smooth.
Once the SS bolts and nuts show up ill be able to tack the nuts on the plate and paint the parts. I want the nuts tacked especially for the 4 bearings as I imagine they will be a regular service and replacement item. This way all I need is one hex key and ill be able to change them out in 10min.

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2,784 Posts
Cool. You had done a great job so far, I should have let you show it all before commenting.

Keep up the good work, I am definitely following this one.


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1,585 Posts
Wow, that is beautiful work! This thing is going to drive like a dream!

I was rowing my van back and forth across the mountain that is between me and the beach I like.... I used to drive this road for fun in my MG..... I am drooling at this mod. :)

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106 Posts
Discussion Starter · #19 ·
Thanks guys, im trying my best to do the best job I know how and put some pride into it.

last few days have been busy, I got the frame bolted up to the body which meant I can start to figure out my steering shaft as well as the PS hoses. As it turned out I only had to go get one hose made. If you decide to do this make sure you get the hoses from the ford Truck especially the ends where they plug into the rack.
Below is the feed/ pressure side of the hose to the rack that I needed to have made. So I measured it out and cut it to size. You will need the Astro part of the hose on the top right. And the ford part on the lower left.
20160104_190115 moded.jpg
After I took it to have crimped at Hose Headquarters they informed me that it would be best if they made a new hose with some crush fittings on the steel ends. As they did not have a crush sleeve to match the factory Astro one. So this is what they made me, it is actually better anyway, now I can totally make sure the hose ends face the proper directions and tighten it down in that orientation. Also it allows me to add a pressure adjustment valve in line should later if need if the steering is to fast / sensitive. Which is something I read can be a issue when going from a Box to a Rack.

The other ford hose that comes out of the rack is the low pressure side and it goes to the cooler. So it can just be cut to length and clamped onto the cooler. One thing about this hose is it has a restriction in it. Looks like a brass fitting with a smaller orifice mid hose. It has a steel crimp sleeve holding it there in that spot. So when you cut this hose make sure you cut well after this mid hose sleeve. I'm not sure if it will be necessary but i'm leaving it in for now.

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106 Posts
Discussion Starter · #20 ·
Next I tackled the steering shaft. I will be using the complete ford shaft as well as the upper portion of the astro shaft. Seems like it will work out very well as the top of the ford shaft is a 3/4" D shaped shaft input. The astro is a 3/4" Double D so all I had to do is file down one side and make a D and make notch for the bolt on the other side. Once I figured out my length I decided to cut a bit off the astro shaft.

In the next couple of pics you can see the flat area needed for the astro shaft to slide into the Ford shaft. And the bolt slot filed in on the other side. I did this mostly on a disc sander and finished with files making sure of a nice snug fit.
Here it is put together
20160104_161204 modded.jpg

Because this shaft will have 3 universal joints it needs a steady bearing. The upper portion of the Ford shaft is just over 1" OD. Something like 1.030". So this is the best part of the shaft to place a 1" ID bearing on. To take the ford shaft apart it has two crimp points under the dust seal, I just pried those up and the shaft slid apart.
20160104_172757 moded.jpg
I used files while I had it in the lathe to get it down to 1" OD as I could not mount it in there to run true. My chuck is to small so it wobbled. But I eventually got it down nicely to 1" OD and a good fit in the bearing.
So now I modeled up a plate that will bolt to the frame using the original mount holes of the old steering box. It will be cut from 5/16 plate and will give me a good stiff place to mount the steady bearing. Should have the plate tomorrow so we will see how close my measurements were. :)
Steering Steady Bearing Mount.JPG
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