radius arms or three link? SAS F150

jsudar

Well-Known Member
Location
Cedar Hills
I am putting a solid axle under my 97 F150, but I'm not sure which link setup to use. I will be using coilovers with 12-14" of travel, maybe 16's if they will fit. I definitely want to use a panhard bar since the truck will be street driven and thrashed in the desert. I still want to have decent flex just in case I need to do a little crawling.

I am considering three options (all will use a panhard for lateral location)

1. radius arms on both sides (like an RE long arm kit)

2. single link on one side and radius arm on the other (like waynehartig's ride)

3. three link-- two lower links and one upper to control axle wrap

My questions are:
1. how well do dual radius arm setups flex? do they rely on bushing distortion to get flex or could I use heim joints?

2. How important is it to control caster loss/gain? any setup with radius arms will have caster change as the suspension cycles, but a three link can be setup to keep caster fairly constant.

I would prefer to build a radius arm setup for simplicity-- easier to set up and easier to fit, but I am worried about the caster change with that much travel.

Let me know if you have any thoughts.
 

I Lean

Mbryson's hairdresser
Vendor
Location
Utah
I am putting a solid axle under my 97 F150, but I'm not sure which link setup to use. I will be using coilovers with 12-14" of travel, maybe 16's if they will fit. I definitely want to use a panhard bar since the truck will be street driven and thrashed in the desert. I still want to have decent flex just in case I need to do a little crawling.

I am considering three options (all will use a panhard for lateral location)

1. radius arms on both sides (like an RE long arm kit)

2. single link on one side and radius arm on the other (like waynehartig's ride)

3. three link-- two lower links and one upper to control axle wrap

My questions are:
1. how well do dual radius arm setups flex? do they rely on bushing distortion to get flex or could I use heim joints?

Reasonably well, when set up right. Yes, they rely on bushing deflection during articulation, so if you use heim joints at the axle you'll lose (or eliminate) articulation.

2. How important is it to control caster loss/gain? any setup with radius arms will have caster change as the suspension cycles, but a three link can be setup to keep caster fairly constant.

Not a worry. Street driving isn't going to move enough to change caster enough to notice, and during big travel you're probably jumping or similar, so street drivability isn't your primary concern at that moment. :)

I would prefer to build a radius arm setup for simplicity-- easier to set up and easier to fit, but I am worried about the caster change with that much travel.

Let me know if you have any thoughts.

There ya go. :D
 

Milner

formerly "rckcrlr"
I vote radius arms. Select a good rubber bushing (think take offs from a new superduty) for the axle end and you will get plenty of articulation for crawling. When fully flogging a big truck in the desert, radius arms will hold things in place better and take the abuse. Radius arms make it more controllable and predictable at speed and under power. Also your most stable option at speed.

Second choice would be 2 lowers and a centered upper, or 2 uppers and a centered lower. Less loading effect then the r-arm on one side only. I would be concerned about big hits at the tire as it would put a big shock load on the single outer arm. But could be built strong enough.

For a go fast big truck, I would advise against a single r-arm or two links on one side and a single link on the other. The loading will be exagerated when cornering at high speed, especially if you have to get in and out of the power. Also same issue as above if you take a big hit on the single link side. If you plan to jump it, take offs could be a little wierd and off chamber landings could be a handful.

You may not need a sway bar with a 2 radius arm set up, but you WILL need one with the other options!

JMHO:)
 

Bucking Bronco

................
Location
Layton
If you want the best of both worlds check out cage arms They are sweet. Sexton offroad has them and The will work if your going to a D60 or to a D44 with the wedges

There kinda spendy but for something you want to do both off road and on, they would be my first choice
 

jsudar

Well-Known Member
Location
Cedar Hills
I appreciate the feedback. I will definitely go with the radius arm setup.

A friend gave me some radius arms and bushings from an early bronco. Are those a good choice or are the arms too short? I've got HP D60 for the front end, but it doesn't look like I will have enough room on the short side to weld in wedges anyway, so I don't know if it's worth the trouble to make them fit.

Can you get those new Superduty bushings separate? Knowing Ford, they probably only service those bushings by replacing the arm.

I have heard some people talking about using stock jeep rubber bushings? would those be a good choice?
 

Bucking Bronco

................
Location
Layton
go check out fullsizebronco.com they will have every question you ever need already answered and lots of what not to do.

The stock arms are too short and to get a lift with them you have to use drop brackets and they hang up on everything.

on the 87-91 D60 you can fit the wedges you just have to cut a notch in them.

My vote is still the cage radius arms that sexton offroad has for I think 725.00 and that comes with the bracket that will fit on the short side of the D60

If your D60 is from a newer superduty you wont fit anything on the short side.
 

UTIBronco

New Member
Location
Park City
Here is a shot of my bronco I have radius arms with a track bar/panhard bar feel free to ask me questions and there is basically all the info you could need on fullsizebronco.com
img_1722.jpg
 

dustybronco

www.sextonoffroad.com
Location
Kamas, UT
Try this link. This is the kit you are in need of. The SAS (solid axle swap) kit comes with all you will need to weld to your axle as mentioned above. if you have any other questions please feel free to call Carl @ 1-800-378-0313. I am currently still in Iraq but Carl can answer any questions you have or put you in contact with someone who can answer them for you. Semper Fi Dustin http://www.sextonoffroad.com/home/index.php?p=proddetail&prod=F2F1.100A
 
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dustybronco

www.sextonoffroad.com
Location
Kamas, UT
thanks, I should return home soon. Me and Laura plan on a little vacation and then we will be ready to hit some trails. She is planning a big bash for the 3rd of May if anyone is interested in attending give us a call. Dustin
 

jsudar

Well-Known Member
Location
Cedar Hills
Realistically: how much travel?

So, I have decided to go with the radius arm setup, but I am wondering how much travel can I realistically expect to get? Or rather how much should I build for? Keep in mind this truck will be a daily driver.
I found a good deal on some 12" travel coilovers-- is it reasonable to get that much travel from a solid axle street driven truck? I was actually hoping for more (14-16), but most of the similar builds I have seen are only running 9 or 10 inches.

However, I think Rockmonkey was putting 14 inchers on the rear of his cherokee and most of the guys building buggies are running 16 and 18 inch air shocks.

Should I get the cheap 12 inchers or pay more for some 14 or 16's? Or is it unreasonable to get that much travel from a radius arm/panhard setup?

thanks in advance
 

dustybronco

www.sextonoffroad.com
Location
Kamas, UT
I hope this isn't Info overload?

If you are using a stock early bronco set up you will not get twelve inches of travel if you convert to a long arm set up with a heim at the frame and maintain a C bushing you will increase some but the axle will still bind up around 9 or 10 inches. if you convert to an after market arm that allows the proper twist for flexing you significantly increase the amount of travel. I would stick with the twelves and limit it to that. You are asking to shift alot of weight around.

CAGE radius arms are multi piece for improved articulation, ride quality and ease of installation. Included in the kit for the D60 is a weld on bracket that provides proper angles and is very easy to install. The brackets flat top allows for mounting 66-79 type Ford 4x4 coils, 80-96 TTB coils, coil over type shock or even air shocks. Holes shown in the brackets are for inserting polyurethane bushings (included in the radius arm kits). These bushings provide for greater axle articulation through the dissipation of axle torsional twist over a broad surface area.
1/4" laser cut side plates are designed to provide for a 7 degree angled mount which helps clear large tires during turning yet still bolts right up to our radius arms. The brackets are 1.5" wide to bolt to CAGE radius arms and to facilitate easily welding to short side axle tubes such as those found on many Dana 60 front axles. A left and a right tubular radius arm is then bolted to these units via a bushing set and four grade 8 5/8s bolts (two per side). At the rear of the arms is 1.75 thread x 1in. bore Teflon lined spherical rod end which is then bolted to .25in plate frame brackets with a grade 5 bolt. The frame brackets are attached to the frame with three bolts. We do highly recommend that these two brackets be welded to the frame as soon as possible for maximum strength.

Performance and technical overview: In regards to the added bushings between the cast head unit piece and the actual arm itself these are needed for two reasons: first they allow for additional isolation since the rear radius arm bushing was removed but the main reason is that they provide more surface area for the front axle to twist onto. This is necessary when articulating the front axle as the dropped axle side twists slightly different than the up axle side. This is what the wristed radius arms are trying to account for by letting the axle flop around on one side. By adding the additional bushings to the front of the radius arm near the axle, the axle is allowed to twist as needed for suspension articulation but does not allow the rapid flop or buckling type of twisting that results in rollovers (rapid weight transfer is normally the culprit here) associated with wristed types of arms. The CAGE design also allows for equal articulation side to side as opposed to the non equal wristed type of arms.
What longer radius arms do is to change the geometry of the front end. By extending the radius arms there is a greater potential for travel over stock arms. Also, because they are longer the angle that the arm is at when the tire is at full droop is less with a long arm than with a short arm. This means that the tire will roll over the obstacle easier rather than wanting to fold under the vehicle. Short arms actually have to move the axle forward slightly before going upward. The shorter the arm the more this is an issue. Longer arms lesson this issue a bunch resulting in easier movement over obstacles. For reference this can be seen very easily on Jeep XJ Cherokee vehicles lifted without going to longer arms due to their short stock arms.
This longer geometry also provides a much smoother ride. This is because the pivot point is farther back on the frame. This allows suspension jolts (think hitting a pot hole edge or speed bump at speed) are transmitted more in a horizontal movement along the frame as opposed to at an angle directed towards the frame. By directing this force along the frame the ride feels much smoother.
The arms have 4.25 degrees of castor built in to improve steering self centering properties and to help the vehicle track straight going down the road (less wander).
There are two main angles in the arms. The first is the most noticeable to people in that they are bent in to clear larger tires when turning. The second is the vertical clearance. The bottom of the plated area angles up heavily towards the top orientated 5/16 wall tubing. This upwards angle and top orientated radius arm tubing (in relation to the axle tube) allow for greater trail clearance at the arm than on stock arms. Stock arms are center orientated in relation to the axle tube.
CAGE Offroad arms are built entirely from raw steel. This means no worries of cracked welds from improperly welded and extended stock arms or worries of bent stock arms being fatigued. We use 1/4" steel plate combined with 2" x .313" wall tubing.
These features account for tremendous articulation, excellent on road driving manners and superior all around driving performance.
 

jsudar

Well-Known Member
Location
Cedar Hills
Ok, so I went ahead and bought the "cheap 12 inchers" which acutally ended up being 10 inch travel 2.5" Radflo shocks from Scott Creasey. See the classified section for that story. I was pretty upset, but I thought maybe I could make them work anyway.

I talked to Ben Hanks for a bit at the Offroad Expo and he said he would run at least 14's if not 16 inch shocks. He said that I would probably be disappointed in the 10 inchers.

After reading Dusty's doctoral thesis, I am leaning toward the Cage arms and have definitely ditched the stock arms/C bushing idea. (thanks DustyBronco)

I'm torn between trying the 2.5 "10" travel Radflo shocks I have or getting set of 14's. There are several racerunner 2" 14's in the classified section right now, but one shock would be as much as I have into both my Radflos.

Any input/trashtalk/or more laughing at my or Creasey's expense is welcome at this point, with the former being the most helpful.
 

Bucking Bronco

................
Location
Layton
When you see those cage arms in person you will want them. They are an awesome product and nearly indestructible. I was going to put them on my bronco but ended up selling it and building a buggy. They take all the work out of an SAS
 

I Lean

Mbryson's hairdresser
Vendor
Location
Utah
Not much input, but I know someone who might actually be interested in those 10" Radflo's. (for an A-arm setup, so the shorter travel is actually appropriate)

If I were going to the effort of what you're thinking about, I wouldn't bother with the 10's. Even though that can work just fine, you'll be the same amount of work to mount longer ones, and that'll give you more potential travel.....
 
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