Another 2wd Extended Radius Arm Question

[Hardwareman]

I know some of you guys have made your own extended radius arms and wondered how you actually determined how long to make them.

Can I go buy a cheap set of stockers at my local pick-n-pull and take those to my welder?

Also, I no longer have my stock radius arm brackets. I have a 4" drop down bracket kit there. Can I still use them and just move them back?

What kind of material should I use? Thanks guys.




Allen

 

[Hardwareman]

I really want to do this guys.

How do I know I'm putting the brackets in the right spot on the frame because I'm sure it matters for alignment reasons. Thanks.

Would it better to buy an aftermarket set of extended ones rather then try to make my own?




Allen

 

[4x4junkie]

You'll need to take a measurement of where the wheel hub is.

Maybe hang a plum-bob from the top of the fender directly over the wheel hub, locate your radius arm brackets where you want them on the frame, then assemble the arms so that the axle is maintained in the same position.

In some cases it may be possible to move the axle forward slightly, too (make sure everything clears by cycling the suspension if you do this though).

You should still have your stock RA brackets, they're probably just attached to drop-down extensions.
Stock RA brackets can be used, but the angle on them won't let the bushing sit "neutral" at ride height, it'll be contorted at an angle. This can restrict it's movement and/or shorten the bushing's lifespan.

 

[Hardwareman]

Ok, that makes sense. Like take my wheel off and plumb a center line on the hub?

What can I do about the radius arm brackets then?



Allen

 

[4x4junkie]

I built mine from scratch

(more pics are on my BII Cardomain page)

You might also be able to use the ones from a '73-'77 F-150 4WD. IIRC these put the arm (bushing) right under the framerail also.

 

[Hardwareman]

I know I know, you've got fab skillz though, I don't.......lol.

Can I ask what you made yours out of and are they straight or angled like the originals?

I'm thinking of getting some bent beams soon to install for a little more lift and was'nt sure how much longer then stock to make them. What do you recommend?

Thanks, Junkie.




Allen

 

[4x4junkie]

The "donut" for the bushing is angled downward very slightly on mine (to match the RA's angle).

I used 2" wide CR steel strip (3/16" thick) to make them. The "donut" I made using some of the leftover DOM tube from the arms.

If you're not sure on fabbing them, then I'd probably look at the '73-'77 mounts. IIRC, they can be bolted on.

12-15" over stock length is a good range to shoot for (mine are 12" extended)

 

[spdcrazy]

not to thread jack here. but i will be in his shoes very soon. and i like to think i have some fabbing skillz.. haha. but when you extend ur radius arms, should the drop brackets be used or just the stockers? i'll be fabbing my own brackets for the bushings.

 

[Hardwareman]

Hey Junkie,

So I went to my pick-n-pull today for other parts and started looking at a 72 and a 74 Fullsize Ford Customs. Are these the trucks you are talking about? The brackeets look rather small and have an eyelet that attaches to the crossmember. Will these work. I'm going to need to grind them off. Thanks.




Allen

 

[4x4junkie]

Pretty sure, yes (I'm not sure the lower end of the year range, but the latest Ford would be 1977 ('78-'79 ones hang down much lower, which will eat up some of your ground clearance). The bracket should be bolted (riveted?) to both the side & bottom of the frame. There may be bolts attaching it to the crossmember too, you won't be reusing those bolts (no crossmember on yours lol, although you could probably make one for it)

As for having the brackets dropped, it will depend on how tall your lift is.
2.5-3" lift: you shouldn't need the bracket dropped.
4-6" lift: I would add 3-5° caster correction to the arms instead of dropping the bracket.
Above 6" lift, you'll want the bracket down an inch for each inch above 6" lift (5° caster on the arms).
(this is for 4WDs, not sure how much is needed on the 2WD)

 

[Hardwareman]

See, that's what I don't/can't understand. How do I measure caster and all that. Do I need to buy one of those angle measuring devices?




Allen

 

[4x4junkie]

Having one would certainly make it easier.
Try to find one like this that has magnetic sides on it so you can just stick it to the knuckle, beam, wherever and leave it.

Measure where it is now, and then just match it up when you build the arms.
(this provided your trucks handling (and steering return-to-center) is good currently)

 

[Hardwareman]

Hey man, I really appreciate the time showing me a "how to" first of all..........second of all:

Where can I buy something like that? AND

How would I measure from a 2wd point of view?

Sorry Junkie for all the questions, but I love these "I-Beam" Rangers (would'nt mind owning a mid-80's 4x4 myself) and would love to know how to properly set-up the front ends. I know they give "shops" A LOT of trouble. I'm sure you know what I mean...haha.

EDIT: Is this measured with weight on the suspension? Again, sorry for being so dumb about these supensions.



Allen

 

[Mutant Pony]

I used the TTB 1/2 ton radius arm mounts. I made them the right length to pivot in the general location of the rear of the front drive shaft. That put it right behing the cab mount. I had to notch the 1/2 ton mount just a little so that it formed around the back side of the cab mount. You can still buy these mounts new from Ford.
I started building a 2wd offroad truck but, it is on hold for now.

 

[Hardwareman]

Well I have a 4" RC lift on my Ranger now with 6" SJ coils. I want more lift and plan on running an 8.8 with 5.13's so I can comfortably run 33's or 35's. I'm currently looking at getting some 4" bent beams (AutoFab) at a good price, so I'm trying to figure out how long and how to measure for extended radius arms.

I already have the dropped pitman arm, and according to "AutoFabs" website I will not need any dropped pitman arm to correct caster or toe because it's already close enough to spec.

That's what's fueling this recent desire to figure out how to do this. Please help me guys. I KNOW YOU KNOW HOW TO DO IT! I've been on here too long to think otherwise. I'm NOT trying to be sarcastic either. Thanks.



Allen