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77 F150 leaf spring conversion

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Old 11-18-2008, 12:00 PM
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77 F150 leaf spring conversion

So here is the deal. I have a 77 F150 4x4 that I picked up cheap due to some rust issues. One of the rust issues has to do with a collapsing front coil spring cup, which needs replaced. Since this truck has 3.50 gears, and I have a set of 4.10 axles (d44, d60) out of a 78 F250, and I plan to run 36's on it, it kinda makes it a no-brainer to step up to the F250 axles. The whole goal of this truck is to provide a weekend beater on the cheap to save some wear and tear on my 05 F150. It doesn't have to be pretty, it's just gotta be tough, reliable, and cheap.

So here is what I have: I kept all of the suspension components from the F250, springs, shackles, hangers, brackets. I even have the whole steering system from the F250, (tie rods, drag link, complete steering box). My original plan was to simply bolt the F250 hangers onto the frame of my F150 and bolt up the axles like a stock F250 setup. I then realized that the frame of my F150 does not have any of the holes for the bracketry, so I will have to drill all new holes. Another sticky point is that I would also like to lift the front 2-4" to better clear the 36's. I planned to just buy a set of super duty springs to accomplish this with the stock-type bracketry and be done with it. But seeing as I have to spend a bunch of time drilling holes in the frame just to bolt up the stock bracketry, I figured that I might as well put that time into making new spring mounts that are not only tougher, but will give me some lift while still using the stock springs. Makes sense, right?

So here is the plan: Concerning the front suspension only: Fabricate dropped front spring mount and new rear spring mount that will give me ~ 3" of total lift. For the back mount, I plan to make a bracket out of plate steel and use a rear spring shackle (see TheTinian's setup for reference) to accomplish the lift. My big question is in regards to the steering. The F150 steering is a horrible design for a solid axle, allowing the toe to move as the axle moves up and down, so I planned to convert everything to the F250 steering. Do I, however, have to convert to crossover steering to make this work right, or can I just get a dropped pitman arm. If I can just use a dropped pitman arm, what should I get?

Any thoughts, suggestions, opinions, comments are welcome. I plan to swap the axles next week while I am on vacation.
 

Last edited by ford141; 11-18-2008 at 12:03 PM. Reason: stupidity
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Old 11-18-2008, 12:16 PM
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Even the stock F250 steering is terrible in the 78 truck. That short drag link and push / pull design is horrible at best.
You will have to perform some interesting fram upgrades just to squeeze that 78/9 power steering box inside of the frame. The crossmember will make that an interesting venture. Your existing box is suitable, and the problem you have is with the inverted "Y" design, and not entirely with the steering system. Instead of this system you can and should go with the inverted "T" design, and call it good. This will be fine for the minimal lift that you intend to run.
Now, the suspension modification that you intend to install is reasonable, and will require some fabrication, and to me, it seems that you will not gain anything by throwing some front leafs up front. You are not changing the axle, and will still have a D44 up there, so other than running leafs, is not really gaining you much. Seems like it would be more reasonable to just replace the spring bucket, and be done. Much easier to run what you have, and the coil spring set-up is plenty strong.
You also intend to run a rear dana 60, and again, with a 30 spline rear axle, you once again will only gain a minimal amount of axle strength. This is mainly because of the difference in axle design, full float VS semi float, but in this case, the 9 incher can hold its own.
Save some money, and keep the wheels that you have and keep fabrication to a minimum by just fixing the parts that need to be fixed.

Mounting the shackle pivot correctly will be the toughest part of your intended modification, but again you are not gaining any strength, and this seems like bunch of time without a reward.
 
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Old 11-18-2008, 03:51 PM
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Originally Posted by 75F350
Even the stock F250 steering is terrible in the 78 truck. That short drag link and push / pull design is horrible at best.
You will have to perform some interesting fram upgrades just to squeeze that 78/9 power steering box inside of the frame. The crossmember will make that an interesting venture. Your existing box is suitable, and the problem you have is with the inverted "Y" design, and not entirely with the steering system. Instead of this system you can and should go with the inverted "T" design, and call it good. This will be fine for the minimal lift that you intend to run.
Now, the suspension modification that you intend to install is reasonable, and will require some fabrication, and to me, it seems that you will not gain anything by throwing some front leafs up front. You are not changing the axle, and will still have a D44 up there, so other than running leafs, is not really gaining you much. Seems like it would be more reasonable to just replace the spring bucket, and be done. Much easier to run what you have, and the coil spring set-up is plenty strong.
You also intend to run a rear dana 60, and again, with a 30 spline rear axle, you once again will only gain a minimal amount of axle strength. This is mainly because of the difference in axle design, full float VS semi float, but in this case, the 9 incher can hold its own.
Save some money, and keep the wheels that you have and keep fabrication to a minimum by just fixing the parts that need to be fixed.

Mounting the shackle pivot correctly will be the toughest part of your intended modification, but again you are not gaining any strength, and this seems like bunch of time without a reward.
75F350, thank you for the reply, and I understand what you are saying concerning the relative strength of the axles. The main reason for the swap is to gain the 4.10 gears for free. The 3.50s combined with the 35's that it has right now make for great highway cruising, but that isn't the intent of this truck. I could regear the 9" and D44 that it has, but as I said before this is a low budget deal, and I got the 3/4 ton 4.10 setup for free, as well as a set of new 36's on 16.5 wheels for free. I can't see spending $500 to regear the stock axles when I only paid $500 for the truck. Oh, and I forgot to mention above that the radius arm bushings are shot, just another thing pushing me to do the leaf spring swap.

While this truck will see offroad duty, it is not a serious mud truck, so I don't think I will have any issues with breaking axles. It will see some, but I am pretty easy on my stuff. It will be used a lot for hauling (firewood, gravel, dirt, scrap, anything else that I can throw in it), so I think the full-floater will hold up a little better under those conditions.

Can you elaborate a little more on the inverted T steering setup? I don't want to take any steps backwards in this category.
 
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Old 11-18-2008, 05:11 PM
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Alright, well I can see where you wanna go with this, and though I still believe that it will be more work than it is worth, I really can appreciate your desire.
The gear ratio might just make me lean towards this direction too.
Alright, well since you are keeping on a tight budget, you dont want to have to go to the full blown X-over steering for your Dana44. This will require machining a pass side steerinf knuckle, and buying a steering arm. This will not be a cheap deal, nor will it be totally necessary.
The inverted "T" style steering, has one solid tie rod, and it ties the two wheels together, just like the 78 dana44 front axle that you have. What it also has is a tappered hole in the end of the pass side tie rod end, and this provides a place for the drag link to be attached.
99 to 04 Super Duty trucks utilize this type of steering and it works fantastic when compared to the push pull system of the 70's.
You have many options here, and you can easily modify the knuckles to accept the chebby 1 ton tie rod ends. While the ends do require a different tapper, these are easy to have machined, or you can buy a tappered bit, or reemer.
Next option might just be to find an Inverted "T" steering set up from the same era truck,, and throw it on there. You will not have the beef of the chebby 1 ton stuff, but if you are easy on the truck, this steering will probably survive, and provide you with years of great steering. By any and all means try not to use the old style steering. This will require some fabrication too, but it will not provide you with any decent steering.
Here is a pic of the bronco with a D60F and simple factory invterted "T" steering. This can be copied using salvage yard parts.
broncohillclimb-1.jpg - Image - Photobucket - Video and Image Hosting

Here is a pic of a little truck with a solid axle swap and a modified inverted "T" style steering, and this is accomplished with spherical rod ends, and DOM tubing.
Image of S series SAS - Photobucket - Video and Image Hosting


Here is a pic of one of my shackle pivots when I converted a 2wd truck into a 4wd. I too used leafs, and wanted to experiment with the use of Johny Joints.
You will gain lift by placing the shackle pivot below the frame, but will have to make rather long front hangers to keep caster angles under control.
Image of Johnny joint in a front shackle - Photobucket - Video and Image Hosting
 
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Old 11-18-2008, 05:49 PM
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something else to consider, you could buy wedges from bronco graveyard and weld them to the f-250 front end and bolt it into the stock 150 radius arms. Then you would just need a track bar bracket fabbed up on the axle. also you could run a '' leveling kit from jeffs, this plus liberal fender trimming would clear 36s just fine.
 
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Old 11-18-2008, 05:52 PM
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Why not put the D60 in the back, and just swap the brakes and spindles to make your front D44 an 8 lug setup to match the 60. If you have the complete setup from the 78 you should have everything. I had a friend who had this setup in his 77 shortbox and it worked well. Drilling holes to mount leafs in the front sounds like more work than changing radius arm bushings. Put a cheap 3 or 4inch coil in the front if you wnat more hieght. The inverted T style steering found on the 78/79 F150 4x4 and Bronco is far better than the inverted Y you have now, and a way better design than the push-pull style that the 78/79 F250 4x4's had.
 
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Old 11-18-2008, 05:55 PM
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Oh ya, someone correct me if I'm wrong, the D44 carrier and gear set from the 78 f250 should swap into the 77 f150's D44
 
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Old 11-18-2008, 06:45 PM
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Ok, the input that you guys have given me has been very helpful so far. This has really got me thinking.

As 75F350 mentioned, I am not really gaining any strength advantage with a leaf spring setup. There is a slight "cool" factor in the swap, but that really isn't the goal of this truck, and is a lot of work just for that point.

I had considered setting up the 3/4 ton axles so I could still use the coils, but I had nixed that idea previously because I didn't know how to get the wedges on the axles, I didn't know you could buy them as a weld-on part, thanks for that advice straightsix. Btw, do you have a link for those? I can't seem to find them on JBG.

I had also had a previous thought about swapping the 4.10's from the leaf spring axle right into my coil spring housing but I was worried about setting up used gears and getting the pattern right so it doesn't eat the gears. The more I think about it, though, since this is only the front axle, and will only be used occasionally at lower speeds offroad, It probably isn't as big a deal as I thought. I have experience setting up gears; I installed the 4.56's in my DD 05 F150 myself and have had no problems in a year and 20K miles.

So here is what I am thinking at this point: keep the stock axle housing, fix the stupid spring bucket, like 75F350 told me to do in the first place... . Swap in the 4.10 gears and 8-bolt spindles, as well as the D60 to gain the gearing that I want. Still only have the amount of the replacement bucket invested to this point.

Once this is accomplished, I can then move on to the steering, which needs an improvement anyways. From what I am gathering, I can just get the linkage setup from a 78/79 1/2 ton and this will be the inverted T design, correct? Will this setup bolt right up to my steering box and the 8-bolt spindles?

I can then add a little lift to clear the 36's without much hassle (it clears 35x12.5s right now with no problem, and one spring bucket is collapsed).
 
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Old 11-18-2008, 06:59 PM
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I think you are on the right track now. Since you have some experience with gear set up, you should have no problem with the "used" gears. These are actually easier to set up since you already have a pattern on the gears themselves.
I always liked setting up some of my used gears sets, and you might get lucky and find that it does not require too many shims to get close.
Yes you can find the 1/2 ton inverted "T" steering and throw it right on your ride. This is simple, and convenient.
What else? That is about it.
Oh yeah, wedges. Two places carry them James Duff Bronco Suspension parts - Long Travel Suspension, Monster kits, shocks, coil springs, leaf springs, radius arms by James Duff
And JBG, for the record, the JBG and Duff's wedges fit for the radius of the 3-1/8" diameter D60 tube(1-9/16" radius). Its the overall legnth that is the problem. They are 5/8" too long if used with the stock radius arms and bushings. The radius of the wedges needs to be ground or machined out to make them shorter, but they do fit the tube just fine. If you use a spacer to spread the radius arm and cap(to avoid machining the wedges), you will need to modify the bolt holes in the lower spring cup to match. The only reason I mention this is if someone were to read this and think the fit on the tube contour was the only problem, they would be very disappointed to weld them on and find out the arms would not close up around them w/o a spacer. Since you have a D44 you can minimize some work, just be sure to measure more than once before you commit, and start glueing things together.
 
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Old 11-18-2008, 08:34 PM
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Maybe I missed it in the reading, but the 250 axle should be low pinion, but the 150 is high pinion. The gears won't swap.

Everything else I would add has already been covered.
 
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Old 11-18-2008, 08:47 PM
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Originally Posted by teds74ford
Maybe I missed it in the reading, but the 250 axle should be low pinion, but the 150 is high pinion. The gears won't swap.

Everything else I would add has already been covered.

F100's and 1 fitties had Reverse spiral alxes. I believe the only low pinion units came in the F 2 fittie until 77.
See here pic 9:

Dana 44 Solid Front Axle: Part 1 Reverse Spiral Housing
 
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Old 11-18-2008, 09:29 PM
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My '77 F150 is indeed a high pinion setup, and the F250 axle, since it is out of a '78 is also a high pinion, so it is a direct swap. As 75f350 mentioned, the 77.5 and earlier F250s (high-boy) are low pinion setups.

75F350, thanks for the clarification on the wedges, that is good to know, and all the more reason to keep the stock housing and swap the gears. I really think that this will be the easiest way to accomplish my goal. Thanks for the help on the steering as well, this thing really handles horrible right now with the stock steering and oversize tires; the geometry really needs corrected. I think the later 1/2 ton setup is the easiest way to do this.

While we are on the subject, where can I find a new lower spring cup (mounts on the radius arm)?
 
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Old 11-18-2008, 09:37 PM
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Again, I beleve you are still on the right track, and you could probably find a decent spring cup at a salvage yard, or check with some of the sponsors on the left.
Glad we had a chat. Sounds like with a little experience and having done this a time or two we may have provided you with some options to make a great decision.
I am confident that have seen the parts that you need on JBG, but others may have these as well.
 
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Old 11-18-2008, 10:23 PM
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Again, thanks 75, and all, I'm glad I posted because I think this will save me a lot of work in the end.

I have a lot of experience with the 2wd trucks, I've had 3 of them, but this is my first 4wd dentside. I even converted my '79F250 2wd to 1/2 ton running gear with 5-bolt hubs, but I've never went the other way. Thanks all for the help.

Btw, here are a few pics of Super Blue for your viewing pleasure:




Also on the list to fix next week is patch the floorpans and fix the heater blower. Later this winter the 351M is getting swapped for a 460. This is not just because I want more power (although I do), but mostly due to the 351 having two dead cylinders from burnt valves. It runs for right now, but it is extremely sick, and the current gearing and tire setup just compounds the situation even more...

But at least it has a hood scoop!!!
 
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Old 11-19-2008, 11:44 PM
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shouldn't have posted those pics, now I remember when you bought that super cheap and made us all so jealous, haha I like it by the way. I'll PM you the jbg link, might get the ban stick if I go linking stuff....
 


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