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Discussion Starter #1
I'm in the process of building a '49 Ford F3 pickup. Once it is finished it will be my everyday driver so I'm looking for ride comfort. I've already swapped the front axle out for a Dana 44 TTB axle to improve the ride and I'm thinking of ditching the leaf springs in the back and building my own 4-Link suspension.


I'm not lifting the truck or doing any of that stuff so I think it will be fairly straight forward to build one. I would like to hear from others who have built their own 4-Links and understand the issues and struggles that they had when building them.


Also please avoid the comments of "Save your time and money and just keep the leafs". I understand its a lot of work to do this but I'm not worried about that so just any helpful comments to better prep me for starting this would be great.


Also if anyone has any good literature they can recommend I'd be happy with that too.
 

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I'm in the process of building a '49 Ford F3 pickup. Once it is finished it will be my everyday driver so I'm looking for ride comfort.
An independent front suspension will do far more for ride comfort than changing the rear suspension. I have both a solid axle 86 Chevy 4x4 and an IFS 99 Chevy 4x4. Both have leaf spring rear suspension, but the IFS rides MUCH better.
 

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Discussion Starter #3
An independent front suspension will do far more for ride comfort than changing the rear suspension..
I understand that and is the whole reason why I swapped the front axle out. But if I can improve it more then I would like to.


Also I think it would be fun to build a 4-Link so that is pushing me that way too.
 

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4 link

I have built a triangle 4 bar and purchased a full set. I see the Weld It series has a set for about $360. I recommend buying a set rather than build because all the TIG work has been done and no Heims joints. While installing them think about a set of air bags for the back too. Cheaper than coilovers and much easier to adjust...push the button! No need for fancy stuff, just two bags, lines, gauge and a compressor.
 

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4 links

i built one for the rear end of my Tbucket. it's really straight forward and just pay attention. making sure bars are parallel to ea other. the main thing and HIGHLY recommend is a left hand tap. this way u use a right hand on one end and left on other and will make a WORLD of difference to adjust. there are bracket kits out there that i used but i built my own rods out of SS.
if u blow up the pic of bucket u can see the lower one.
 

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Here is a link with some general tech and overview of whats required along with a link the 4 link calculatior and other links that will get you started on the math without spending a cent on any physical books.

It Mainly talks about 4x4. But the practices and techniques can apply to stock, lowered, or slammed rides also.

TRS Magazine - 4-Link Suspension

Having a weight of the thing is a geat starting point. Cat scale on the back of a trailer with parts in the trucks bed if need be to get close to that weight will help when your 4 link calculations. If you already have the thing tore down or are building it from the ground up then you can find hanging scales easily enough that will give you an idea of the weight of things.
https://www.walmart.com/ip/500-KG-1...9983&wl11=online&wl12=180948207&wl13=&veh=sem

Or if you have a deer scale around they are usually good for 300lbs.
https://www.cabelas.com/product/Cab...VkLfACh1YoQbkEAQYBiABEgISTfD_BwE&gclsrc=aw.ds



One thing I will stress on is Heim quality. You do have options when it comes to heims. I like Ruffstuff because they have Beef and you get a lot for your money. The 1.25 rod ends speak for them self once you hold one.

ROD ENDS/HEIM JOINTS/UNIBALLS - RuffStuff Specialties

But that beef comes at the cost of weight. We are talking about weight in the area of 1/4 thick brackets vs 1/8 though and when I am shooting down the road at some crazy speed and get a bit of air over a hill I am glad I did not go with the thin stuff.


Ruff stuff has "kits" for your front axle and many rear axle combinations which will add a truss to the axle and weld to that. You are still welding and grinding to get an exact fit to your frame/axle. But the stuff is very close right out of the box.

They offer kits for both upper and lower triangulation as well as both.
https://www.ruffstuffspecialties.com/catalog/4LINK-KITS.html


This is one company I have never bought anything from and was like that was really only worth 1/2 what I paid or I could have built it for that price. They have built a reputation of very high quality parts at a very fair price.
 

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Discussion Starter #8
Having a weight of the thing is a geat starting point.
How important is it to have the total weight? I'm doing this build from the ground up so currently All I have is the frame and I'm finishing the install of the TTB Dana 44 up front and still working on mounting my engine/transmission/transfer case. I've read that you can use the top bolt of the bell housing to estimate center of gravity. Is this close enough?
 

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Discussion Starter #9
Also thank you all for you input/insight. I have decided that I'm going to build a 4-Link for sure just need to keep doing some more research before I start.
 

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Discussion Starter #10
While installing them think about a set of air bags for the back too. Cheaper than coilovers and much easier to adjust...push the button! No need for fancy stuff, just two bags, lines, gauge and a compressor.
I'm for sure going to be putting bags in! For what I want to do with the pickup they will be the best.
 

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Discussion Starter #11
One more question, how important is it that I use 1.25" Heim Joints? I'm not doing any 4x4 stuff with it, just going to be my everyday driver. I will have a decent amount of power (Shooting for 550HP with a 445 FE motor).

Is that kind of power a must to having the larger Heim Joint?
 

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I’d trust 1” QA1’s and FK’s if you keep a close eye on them.
Get them with seals and use graphite for longest life. Which is still pretty short compared to bushings.
 

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The total weight is just a nice tool to have. But yea if your building from the ground up just rolling over a scale then weighing the old leafs etc and the new etc before building a linkage setup is not a option. You can get an idea of the weight by asking others with similar rides. But I have also had a 76c30 with a 350 sm465, 14 bolt weigh 4040lbs and had a 84 c30 with the exact same drive train and all the same options and equipment weigh in at 5020.

Difference was in the flatbed design. The lighter one was made of wood/aluminum and the frame had been cut right behind the spring perches. Think it was around 6-7 feet of bed.
The other one had a stake bed made of heavy steel with thick wood and was a full 8 feet wide and 12 feet long.

Just an example of two trucks that may fit in the same category but are in two different classes when it comes to weight.




Not having the weight is no deal killer. It just avoids ordering multiple springs and shocks to achieve the linkage length and angle you want the thing to sit at finally. Basically add a small 1/4" bead in say 4 points on your mounts so they are close to perfect and continue building the thing. You want these tacks to hold up to the abuse to going over some bumps and buddies jumping on the bumper yet still able to grind the things off.
Once it is a full roller at the height, stance, feel that you want(yes I want to to drive it around the yard gently), you can move those links and mounts so that nothing binds. You may need to order longer links as a result. But the final result of nothing binding or someone looking at the thing and having that look across there face of what the heck you were thinking.

No shortage of people to tell you if you have done something wrong at a car show. Or ask you if you have done something in a specific way. Some steering linkages and suspension linkages look down right scary. But others may not look normal yet function beautifully.
Air bags 1/2 way up trailing arms is a example of this. Done right the thing will function perfectly. But it may still have people thinking it does not belong or is unsafe.



With bags you have an adjustable spring rate to a degree. You can adjust the pressure and use height control valves to set the ride height. But that bag has a sweet spot and it is easy to go to high or to low placing additional stress on your shocks, linkage, and axle tube.
How you mount your bags(there are many methods) will affect your linkage, shocks, backspacing, exhaust, and so on placement. Generally hitting up google searching for images or going on forums with similar frame/drive train combinations of air ride setups with similar suspension and drive train layouts will give you an idea and get you close what may work best for you.
 

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One more question, how important is it that I use 1.25" Heim Joints? I'm not doing any 4x4 stuff with it, just going to be my everyday driver. I will have a decent amount of power (Shooting for 550HP with a 445 FE motor).

Is that kind of power a must to having the larger Heim Joint?
No you don't need the massive heims. I had heavy truck, and 4wd to go off of and always would have more strength then not enough when it comes to suspension components. That being said most of the requirements for the tougher heavier joints does refer to the misalignment caused by flexing. In some setups a johnny or bushing setup may work.

Johnny joints tend to be a nice middle ground strength wise and provide a quieter ride over heims which may clunk or squeak.
https://www.currieenterprises.com/johnny-joint-rod-ends

Getting into trailing arm territory here. But depending on the link angle bushings can be used just know that if the angle is to steep you will have the upper right and lower left,etc of the bushing doing all the work shortening bushing life

Anatomy Of A Suspension Link
 

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Here is one that I keep needing to buy as it keeps getting borrowed for projets never to return.


https://www.amazon.com/Race-Car-Vehicle-Dynamics-Experiments/dp/0768011272



But thinking about 4 links will keep you up. Look at what others have done and somewhat copy there design. What works on one truck may not work on another there is just so many differences like I said with the c30 thing above. So you want some adjustment. If you don't see running fat tires and have straight rails that are straight from the frame back then straight lower links may be for you. If you see this thing having some fat tires later and don't want to be forced into having the things sticking out the fenders then angular lower links may be for you as you can tuck them inside the tire.

It is one of those things where if you put your cab on stands at ride height, put your engine in front of the cab hanging off a picker low enough to close the hood, roll your front axle under the balancer, then roll your back axle where it works with the cab then you can start thinking about how wide your rails can be with your final tire size keeping backspacing in mind, turn your wheels and find out where your front rails need to be so the tires wont hit, then figure out what link style will work with that chassis setup so that you don't have things hitting other things like the upper links hitting the bed because you mounted them on top of the diff or your lower links 4" off the ground and scraping on speed bumps, or forced to put the bag or shock right next to the exhaust.

Doing the setup alone will let you actually see the final height of the thing and get some of your measurements you will need for link setup.


Think about maintenance. A engine stuffed back into a recessed firewall so you can lower that engine placing it behind the front axle tube sounds great until you want to do something simple like change one of your rear plugs. Adjusting your suspension and steering linkage is no different. You want to be able to get a wrench up in there at rest not needing to fight with adjusting those links.
 

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Like cerial mentioned, I went with Johnny Joints from Currie on the bars for my Astro. Made sense as they are very stout, greasable, rebuildable and provide lots of articulation to keep the suspension from binding.


All welded and painted during final mock-up...


Mark
 

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Discussion Starter #18
Thank you all for your help. I think I'm going to go with 7/8" Johnny Joints. This is what I used for my radius arms on my TTB Front axle. I like them for the fact that I can rebuild them and they are greasable. Certainly a lot that I still have to figure out but I'm at least on the right track now.

This is why I love doing this kind of stuff always keeps me learning and always presents new challenges to solve!!
 
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