Lowered, 2wd, radius arm rear???

strange1

strange1

Well-Known Member
Joined
Mar 31, 2005
Location
Elkin
I’ve been looking for a cheaper way to eliminate axle wrap on my s15 street truck. I have been hearing that caltracs are the best, but at $400 a set plus shipping I figure me and a buddy could link it for the same. While googling others setups, I found this pic of where a guy was starting a 4-link by mounting his lower to the factory spring hanger. Since I will have a gas tank in the way, 4-link is most likely out. My question for the guru’s is: can I start with this lower link, add an upper in a radius arm configuration, a panhard bar, and make it all work?

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I don't see why not... It sounds like a pretty good idea. Should be fairly easy, inexpensive, and would eliminate any axle wrap issues. I may do the same once I start on my S10 project. It'll definitely need something to kill axle wrap with a Duramax in it... :D
 
Croatan_Kid said:
I don't see why not... It sounds like a pretty good idea. Should be fairly easy, inexpensive, and would eliminate any axle wrap issues. I may do the same once I start on my S10 project. It'll definitely need something to kill axle wrap with a Duramax in it... :D
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Duramax? Absolutely. I’m afraid I’m about to break a spring trying to take off quickly with the old iron Duke. I’m planning on a turbo 4.3, so I want to get ahead of it this winter. My truck.....

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I've got an 85 rclb 2wd Iron Duke 4spd and a 93 rcsb 2wd 2.5 5spd. Probably do either a 9" or narrow a 14 bolt or AAM 11.5 for some weight in the back. Stock bottom end LB7, 100-200% over injectors, 10mm stroker CP3, and a biiig single turbo. Something like an S475 or S480. That'll move the peak torque up well over 2000 rpm, keep the bottom end alive, and help get the truck moving before it just melts the tires. Built trans too, obviously.

Should be a fun sleeper, get stupid awesome mileage, and be pretty freaking quick. Aside from the transmission build, injection pump, and injectors, it should be fairly "cheap" to put together. Just need a shop and some time and some money and...
 
I always wanted to build a set up for a diesel truck like the big road tractors have. Cut the leafspring a little behind the axle, mount the air bag behind the axle on the leafspring with square u bolt brackets. Then the only fab is a track bar. Sounds like it would work, but never got around to trying it.
 
NCJeeplover said:
I always wanted to build a set up for a diesel truck like the big road tractors have. Cut the leafspring a little behind the axle, mount the air bag behind the axle on the leafspring with square u bolt brackets. Then the only fab is a track bar. Sounds like it would work, but never got around to trying it.
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I’ve thought about that as well, only replace the leaf-spring completely with a piece of 2-1/2” tube.....
 
NCJeeplover said:
I always wanted to build a set up for a diesel truck like the big road tractors have. Cut the leafspring a little behind the axle, mount the air bag behind the axle on the leafspring with square u bolt brackets. Then the only fab is a track bar. Sounds like it would work, but never got around to trying it.
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Don't forget truck rears have a stuby torque arm on top of the pumpkin to a frame cross member to arrest the axle wrap. Usually on tandem axles they both point to the same member in the middle.
Had to replace this type of frame on several Ladder Trucks for fire service. Not a bad design at all, those where heavily abused and over loaded. A short panhard type bar and your done. Keep everything flat add ride height. Limit the travel for a very predictable arc of motion and let er eat.
With the right spring rate, she'll squat, plant and launch.....or roast the tires!

Edit.....after researching, what I described above was with leaf packs......I just found the set up I think your refering too.
Lower link, trailing bag, with an upper half pack that appears to arrest the axle torq. I'd reall want to see it work, looks more complicated.
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My experience in larger trucks was more the Hendricks style walking beam. Certainly not a single axle configuration.
 
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The radius arm will give you pretty high anti-squat, esp compared to a 4 link. You can use a 4 link or 3 link calculator to run the numbers. The antisquat line will go directly through the spring hanger, so the lower the truck is, the better you will be.

I am not familar with s10 suspension. Where is the gas tank at, in your frame? Could you put a single upper in the center or run uppers directly next to the frame rail, with a panhard?
 
Not much to add other than the Heidts 4 link conversion for 60s Ford cars like my Fairlane and mustangs mount the lowers to the stock front leaf spring mount, then they add a small cross member to attach short uppers and a second cross member to mount the coilovers. Google Heidts 4 link 67 mustang for example pics. The cross members bolt or weld to the stock Ford unibody frame rails. There are guys autocrossing and road racing with these setups.
 
It looks like the rear shackle hanger isnt there anymore, but it could be possible to use that as the frame mount for an upper. As I mentioned before, you could take some measurements and stick those in the 4link calc and see what you come up with. My bet, if you couple that with an upper mount with as much height and adjustment as that lower one, you will find a setup that works.

If you arent sure about the calc, you can post here or PM me, and Im sure one of us can give you the measurements needed and run it for you.
 
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