Beating a dead horse. Traction bar idea.

[6.9poweredscout]

Ok I love simple. I have had great luck with the simple 1 bar on each side design, from bottom of axle, couple foot of round bar, tied to frame, bushings on the ends. Seen this numerous times on tow rigs and competitive pullers. On the travelette I've lost sleep over several designs, but I think I know what i'd like to do. I plan on using this bushing (http://autofab.com/i-9903085-2-tube-bushing-assembly.html) on the frame end and a heim joint on the axle. That busing is HUGE and should provide ample movement as the axle moves up and down. Anyone see a problem with this? remember going SIMPLEEEEEEEEE!

 

[FarmerFrank]

Looks like it ought to work. If your after more travel on traction bars weld a piece vertical off the axel and put the cross bar horizontal to the frame/crossmember. keeps all your free travel and wont let the axel wrap.

 

[franklin2]

I have looked into this a little bit, since I have blocks for the lift on my truck, and do get some axle wrap when towing. I like my ride and the flexibility of the rear suspension. I can't see how you can tie the rearend directly to the frame without it binding the leaf spring when it moves.

The spring grows in length when it flattens out. Of course that is what the shackle is for in the rear. But it also grows from the front spring eye to the u-bolt/axle mounting point. This means the axle actually moves back ever so slightly when the spring flattens out. And then you have the solid bar when it moves up and down, the end attached to the axle is moving in a arc since you have it tied solid to the frame. Too much going on, too much bind. That's why a lot of people install a shackle at the front instead of a solid mount to the front of the bar.

 

[franklin2]

What I am thinking about doing on my truck is making a custom lift block. Make it the same height as the block I have now, but instead of just being a block, I was going to make it into a arm extending forward under the spring with a rubber bumper mounted on the top that would hit underneath the spring, exactly like the old school hotrod traction bars. When the axle tries to twist up, it will a small amount till the rubber bumper hits the bottom of the spring.

 

[racin460]

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
what he said has always been the best findings I've had.

 

[laserjock]

What are you trying to accomplish? If all you want to do is stop axle wrap then yes what you've got here will probably do that. If you are trying to maximize traction for a racing pulling scenario without going to a full on 3 or four link system, you probably should think about doing a top and bottom bar off the housing and bring it to to the frame right behind the cab. It puts the force in the middle of the truck in stead of out where the frame is lighter. If you are thinking about pulling on track with this rig the bars are real important as they can really cause the frame to flex and cause all sorts of problems if you do it wrong. The worst thing you can have happen is the bars load up tension in the frame and it cause the thing to bunny hop down the track because when the tires break loose it lets the chassis unload and it will just keep doing that until you power through it or break something.


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[HiHorse]

I have built a lot of traction bars, and personally like a single link above the axle. It provides the best articulation and you won't lose ground clearance.

 

[franklin2]

I have built a lot of traction bars, and personally like a single link above the axle. It provides the best articulation and you won't lose ground clearance.

I can't find it again, but when I was reading up on it, there was a good article against that type of top mount bar.

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They said the setup above just aggravates the problem. A good way to picture it in your mind is to imagine the truck body and frame not moving, but the tire rolling forward. This makes the leaf spring look like a "S" from the side view, the front of the leaf spring bows up, the rear part bows down, extending the rear shackle. They demonstrated the above bar in the picture does not prevent this from happening. I will keep looking and see if I can find it.

 

[franklin2]

I found the article.

http://www.4x4wire.com/jeep/tech/susp/axlewrap/

 

[HiHorse]

Sorry, I meant a single link, above the center section. I can see why the ones in the photo don't work on some applications.

 

[6.9poweredscout]

What are you trying to accomplish? If all you want to do is stop axle wrap then yes what you've got here will probably do that. If you are trying to maximize traction for a racing pulling scenario without going to a full on 3 or four link system, you probably should think about doing a top and bottom bar off the housing and bring it to to the frame right behind the cab. It puts the force in the middle of the truck in stead of out where the frame is lighter. If you are thinking about pulling on track with this rig the bars are real important as they can really cause the frame to flex and cause all sorts of problems if you do it wrong. The worst thing you can have happen is the bars load up tension in the frame and it cause the thing to bunny hop down the track because when the tires break loose it lets the chassis unload and it will just keep doing that until you power through it or break something.


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yeah I like the "ladder bar" idea with the 2 points at the axle, one at the frame on each side. i'm just worried if it'll bind up when i'm towing the trailer. I plan on towing and sled pulling with the truck. i'll never go off road with the truck (maybe field to drag out a truck) but no serous articulation. then that raises the question, how to tie it in? solid at axle, bushings at frame? I don't like heim joints, they always rattle and clunk when i've used them! open to opinions and ideas.

 

[laserjock]

I have typically done them with heim joints but you are right, they tend to rattle. Don't usually care for the few seconds on the track. That brings me to the next point. With the springs you are running, do you really think you will need them for daily driving? It doesn't take too long to install them if you use pins to hold them in. Could even carry them around with you if it is that common you need them. I'm really not sure why you are worried about them rattling when you've got that DT sitting in your lap.




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[laserjock]

As far as binding, how much travel are you going to have to the bump stops. The way the racing guys would take care of the would be a slider kit on the springs. Not something I ever dealt with but check out the guys that mud race.


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[6.9poweredscout]

Well with the 63" chevy springs and possibly 1300 ft lbs I think they'll want to twist up towing and accelerating hard (who wouldn't mash the skinny pedal with all that torque!). not sure on how much the axle will move, I plan on airbags to assist towing. i'm planning on insulating the firewall and cab pretty good. hopefully the DT will be a dull roar.

 

[binderbound]

If you run good heims they wont rattle or loosen up for a very long time. Try FK or even the cryo treated ones from Ruffstuff specialties. Shock placement will help keep mild wrap to a minimum as well. The 74-75 IH's had the staggered shocks and I notice a big difference in the axle wrap between my 71 1210 and 74 D200. But.... if this is a highway rig that tows and wont wont be twisted up a lot, a single bar on each side would keep things under control. You will want the bar as level as possible though, so that when the axle does swing slightly front to back, the bar can travel. BTW, swinging a 6.9 into my 75 scout now...