I'm looking at giving my 03 6.0 x a 6" lift. I know that lifting can result in stability issues. What is the difference between traction bars, radius arms, ladder bars, 4 link....I'm sure the list goes on?

 

I know that if your track bar bushings go bad you'll hate driving your truck. Get one that's adjustable and make it suit your lift, trust me.

 

Most of that won't apply here. You will need an adjustable track bar and maybe a drop for the pitman.

 

I'm pretty sure any (quality) 6" lift will come with the correct linkage parts for your front axle like the folks above mentioned. However your question was about rear axle setups, so here goes. I'll grab some Bing image search finds to help show examples.

Traction bars: Attach at the axle to spring mounting point and extend forward with a rubber bumper that will come into contact with the forward part of the spring or front mount as the axle rotates or wraps up under hard acceleration. Your factory stock springs came with a traction bar, that thick bottom half leaf with the little snubber on it, it was needed due to the weak springs Ford gave us.
I used to run a set of traction bars like these on my old Camaro. These work by transfering the axle rotaional forces into frontend lifting forces that drive weight transfer onto the rear axle. Cheap, easy and simple.


Radius Arms: Typically mount at the axle to spring mount and extend forward to the front spring mount where they are solidly connected. Most commonly mount under the spring but some designs do mount above the spring. Being the same length as the spring from axle to front mount they allow for smooth up and down spring and axle movement but they eliminate axle wrap by locking the axle in with a solid link. This also transfers the axle rotaional forces into frontend lifting energy to force weight transfer onto the rear axle. Simple and effective, more control of axle movement than traction bars.


Ladder Bars: When used with leaf springs you can have a either a single ladder bar like this.


Or a set of ladder bars like this.


Ladder bars can also be part of a leaf spring replacement when used with coilover shocks like this.


Very similar to the radius arms they are solidly connected to the rear axle and mount forward with a rotating joint to transfer that axle rotation into lifting force to plant the rear. Typically stronger than radius arms and can be a foundation for more evolved suspension setups. And they look cool too!

4 Link: Very sophisticated system that postions and controls rear axle movement via 4 links. Various different designs catering to a wide variety of motorsports. Dragsters, circle track cars, road racers and off roaders have all used 4 links of many designs to allow for great adjustability and control. Off roaders typically run a triangulated setup similar to this, it can allow for extreme articulation.


Popular with dragsters for their light weight and adjustability are setups like this.

Again solid links from axle to frame transfer rotational force into front lifting force directing weight transfer onto the rear. The 4 link setup allows for a wide range of adjustability via the multiple adjustable rod ends to change the geometry of the suspension to achieve a desired action. Very high end equipment that offers the most adjustability.

 

Thanks for the explanation. What I'm taking away here is that they all control axel wrap. The real difference is how much they allow and their affect on driveline geometry as the rear springs flex.

 

traction bars are for axle wrap - we can use them with 99-04 style suspension, but you'll get more benefit out of using a ladder bar

radius arms are utilized in the front to maintain axle position. We cannot use them. they are for the 05+ front suspensions that use coil springs vice leafs.

4 links are awesome...but expensive and you loose the load carrying capability due to using coils out back vice leafs. very articulated though offroad

ladder bars are basically glorified traction bars. there are several styles to each. depending on where you are in the country, you'll hear the terms used interchangeably and it will mean the same thing. I grew up calling them slapper bars (1st pic above) for cars, and ladder bars for trucks


basically, the only thing you can EASILY use of the bunch for your Excursion is the ladder bar to help prevent rear axle wrap. just be aware that they limit articulation offroad

 

Thank You WE3ZS/Tom for the pictures and explaination. Now I can understand those terminaogy and the setup I see on vehicles

 

Traction bars are easily used for our Excursions too.

I have a set of OUO traction bars I bought for my 2-wheel drive F250 that I never put on, so they'll be going on the Excursion instead, since the 4x4 F250 that replaced my 2-wheel drive rig already had a set of OUO bars on 'em.

Stewart

 

OUO bolt on traction bar:



Stewart

 

The OUO stuff is very nice!!

 

I have a set of bars on my truck. They are very heavy, use 2" heavy wall tubing and 3/4" heim joints. The bracket is built in to my rear lift block. I got them from Newton Lifts. He is on eBay. I think they call them Fat Boy traction bars? I'll have to see if I can get a pic on here from my iPad. They are also very long. They go from my rear axle up to the middle of my front doors. I get absolutely no axle wrap and I'm using a custom 8 1/2" rear block that he made and it has the bump stop and traction bar bracket built in. As well as the lift block actually slides over the perch mount on the axle. I also had 3/4" u bolts made. THERE AIN'T NO WAY THESE BLOCKS ARE COMIN OUT. I would recommend Newton Lifts to anyone who wants a set. And his prices are great too.

 

Laugh but I invented those traction masters (in my mind and on paper) in the early sixties and then I was as the speed shop one day and saw them in the showcase.

 

WOW Tom. I feel like I've just watched an Episode of Extreme4x4 and had Ian go through one of his training sessions - except I liked your pictures better

 

sorry man, but he is no Jessie!

 

True, I have a great face for radio..................