Radius Arm Suspension - Mistake or A Move in the Right Direction?

So they ride and drive the same but a 4 link is better? If you can get the same ride quality with 4 moving parts as you can with 10, why wouldn't you go with the simplest setup?

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3 and 4 link have far more adjustability. Like it was said before, radius arms can be set up to provide a fine ride for the road, but the second you start taking performance 3 or 4 link suspensions are superior. This has been proven for decades in the offroad world.
 
But we're not talking performance, we're talking ride quality on an oem truck.

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Something must be wrong with the work truck I drive. 2008 F350 ECSB SRW had it since new now has 60k miles, rides worse than any dodge I have owned or ridden in. It does ok on new asphalt but on anything else (dirt roads, grassy fields, asphalt in rough shape) it spills whatever you have in the cup holders and bounces around the road bad enough that the ass end kicks out every few seconds. In the sand it is by far the worst axle hopping vehicle known to man, 2wd or 4wd.
 
But we're not talking performance, we're talking ride quality on an oem truck.

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As far as a stock truck's ride quality going down the road it's fine. Ideal? Absolutely not as radius arms cannot be engineered to handle and behave like a well setup 3 or 4 link. But radius arms are cheap to produce, simple, and easy to package. Hard to argue with that logic from a manufacturing standpoint.
 
Something must be wrong with the work truck I drive. 2008 F350 ECSB SRW had it since new now has 60k miles, rides worse than any dodge I have owned or ridden in. It does ok on new asphalt but on anything else (dirt roads, grassy fields, asphalt in rough shape) it spills whatever you have in the cup holders and bounces around the road bad enough that the ass end kicks out every few seconds. In the sand it is by far the worst axle hopping vehicle known to man, 2wd or 4wd.

Replace the shocks with a quality shock. Sounds like you don't have any rebound or dampening control with the current shocks.
 
As far as a stock truck's ride quality going down the road it's fine. Ideal? Absolutely not as radius arms cannot be engineered to handle and behave like a well setup 3 or 4 link. But radius arms are cheap to produce, simple, and easy to package. Hard to argue with that logic from a manufacturing standpoint.

Would you consider dodges 4 link well set up with such short links?


I agree with top post, I would rather have the radius arm in a truck because it will be much simpler to keep in alignment and change bushings down the road.

I always a fan of the 67-79 ford cast radius arm setup for off road, converted a few Dana 60's over to that with a wristed arm
 
I don't see much of an issue with the geometry/link length, but the links could be a good bit flatter which is where initial shock of hitting a bump comes from, but overall it's just a generic design meant to please the masses and not really dialed in for anything specific.

Ford's cast radius arms in stock form are absolutely terrible... extend them ~6" with at least a 1.25" heim at the end, triangulate them, plate the sides, and THEN you have something decent for off-road as long as you don't mind insane amounts of body roll.

I'm also curious how you used Ferd's cast radius arms on a D60. The tubes on a D60 are too big in diameter for the radius arm to fit over even without a bushing....
 
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They fit with different C's. We did a 79 f150 last year

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I don't see much of an issue with the geometry/link length, but the links could be a good bit flatter which is where initial shock of hitting a bump comes from, but overall it's just a generic design meant to please the masses and not really dialed in for anything specific.

Ford's cast radius arms in stock form are absolutely terrible... extend them ~6" with at least a 1.25" heim at the end, triangulate them, plate the sides, and THEN you have something decent for off-road as long as you don't mind insane amounts of body roll.

I'm also curious how you used Ferd's cast radius arms on a D60. The tubes on a D60 are too big in diameter for the radius arm to fit over even without a bushing....
That was what I was saying about the link length, being longer makes them stay flatter longer for a better ride, especially once someone puts a leveling spacer on hah

I wouldn't say terrible, they are great for budget minded wheelers who don't want to deal with the axle wrap of leaf springs or spend the $ to build a 4 link.

I always just plated the sides with 1/2" and extended with helms. Wrist one with a replaceable pin for slow off roading.

Fords cast arms onto a 60 is a very very common swap. People that sas a 78-79 60 under 87-96 f150's do it as well as rangers, explorers broncos etc.

Old school way was pre 78 cast wedge axle you grind the wedges off and grind them out to fit the slightly larger 3.125" tube and weld on, now you can buy them made to fit 60's tubes and what ever degree bushings you want.


Now that we are off on a tangent...

I think ford's radius arms provide a simple effective reliable suspension link, especially the new, since dodges "4 link" uses such short arms resulting in poor geometry through travel I don't see a loss here
 
Seems like a huge step in the right direction for durability. Damn frontend components are bigger than my f550 service truck.
 
That was what I was saying about the link length, being longer makes them stay flatter longer for a better ride, especially once someone puts a leveling spacer on hah

I wouldn't say terrible, they are great for budget minded wheelers who don't want to deal with the axle wrap of leaf springs or spend the $ to build a 4 link.

I always just plated the sides with 1/2" and extended with helms. Wrist one with a replaceable pin for slow off roading.

Fords cast arms onto a 60 is a very very common swap. People that sas a 78-79 60 under 87-96 f150's do it as well as rangers, explorers broncos etc.

Old school way was pre 78 cast wedge axle you grind the wedges off and grind them out to fit the slightly larger 3.125" tube and weld on, now you can buy them made to fit 60's tubes and what ever degree bushings you want.


Now that we are off on a tangent...

This guy knows what's up...but that's kindof not on topic
 
This guy knows what's up...but that's kindof not on topic

This isn't a wristed Ferd radius arm and flexed quite nicely. Wristed RA's make quick work of the bushing (which suck at controling axle wrap to begin with) as then the single bushing is what controls the axle wrap.

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The nice thing about building your own linked suspension (to include RA) is you can adjust the caster to get rid of the deathwobble brought on by leveling kits or lift kits.
 
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