What is a 2-link?

[jgbjgb]

I have been reading and looking at pictures.

What is the difference between a 2 link and ladder/traction bars? They seem to look the same and do the same job. Or am I missing something?

[Shred918]

You are right on track. A 2 link is a track bar.

[steveG]

The difference between traditional ladder/traction bars and 2-link kit as most here know it is geometry. Most ladder/traction bar designers (I use that term loosely) don't take leaf spring geometry into account and the bars leaves move in completely different arcs causing bind. They work OK for street vehicle that only see a few inches of wheel travel, but they really inhibit good clean wheel travel.

While I was cycling for shock mounts I decided to check the geometry of the 2-link kit on my truck. I was able to install both bars with the suspension at full bump and full droop with very little work.

A quoted post from Class3racing.com:

http://www.class3racing.com/showthread.php?t=40



it made my F-150 grab hold and take off like it was a new truck. No more spring flex, WAY less shaking and vibrating in the sand washes

That's a great description of what it does for you. I did some testing with and without the bars because I was curious about the difference. Without the bars the rear would still go over everything, but it felt like it was skipping over bumps and was quick to buck and swap side to side. With the bars installed it's like a different truck. The rear stays planted and very controllable. It felt like the wheels were actually rolling over the bumps and dropping into holes instead of the bouncing feeling. Now, the rear actually lifts under hard acceleration like a linked rear suspension instead of wrapping the leaves and hopping up to speed.

I've always been surprised that there aren't more trucks using a similar system. I've seen some damn fast leaf spring trucks with a ton of wheel hop and wonder if they would be faster or at least smoother if they eliminated all the hop and chatter.

[jgbjgb]

Steve,

Read the linked post and also read the links in that post.
According to this link: www.4x4wire.com/jeep/tech/susp/axlewrap/
The best set up would be mounting points on top and below the axle with a front pivot point on the frame, a triangulated ladder bar.

Or something like this: www.truckblog.com/story-1304-howto_install_four_real_steel_traction_bars

[steveG]

Steve,

Read the linked post and also read the links in that post.

Admittedly I only skimmed both. :D

I've read parts of the 4x4wire.com article before and it has a lot of good tech info and from what I can see it is fairly accurate.

As for the "Four Real Steel traction bars". They probably did work great on the Superduty test truck. I'd love to see how they'd hold up in the rough continually cycling 12-18". I'd also like to see what they would do to a long travel leaf spring. Because of the two attaching points at the axle, the traction bar will dictate the pinion angle and not the leaf spring. In other words it's controlled axle-wrap. It doesn't eliminate it. Kind of defeats the purpose. The spring will still fatigue.

The ideal traction-aid would be a triangluated 4-link with floating leaf springs. This way the links will eliminate axle-wrap and help locate the axle laterally. At that point, though, unless your truck is restriced by class regulations, you might as well build a traditional 4-link.

Oddly enough, the only people that I've seen knock the 2-link kit like I have on my truck are those that have never used one. Every person I've ever talked to that has driven a 2-link equiped truck has raved about their merit and durability.

[X9 Racer]

Don't know if this is what you call a 2-link, but this set-up allows the rear to travel +24 inches with the limit straps removed. And it doesn't bog down in the silt beds of Laguna Salada.

[Bulldozer]

Don't know if this is what you call a 2-link, but this set-up allows the rear to travel +24 inches with the limit straps removed. And it doesn't bog down in the silt beds of Laguna Salada.

I don't believe it.

[X9 Racer]

I don't believe it.

I didn't either. I was looking into buying this homemade 7 and got into an argument with the owner, so he took the shocks and straps off to prove it.

Of course it's not all useable travel, part of it is from the shackle swinging from the straight up position to almost pointing down but still I was impressed.

My point however was that a well designed 2-link won't bind, which is what most people that haven't seen them at work seem to think.

[Bulldozer]

I didn't either. I was looking into buying this homemade 7 and got into an argument with the owner, so he took the shocks and straps off to prove it.

Of course it's not all useable travel, part of it is from the shackle swinging from the straight up position to almost pointing down but still I was impressed.

My point however was that a well designed 2-link won't bind, which is what most people that haven't seen them at work seem to think.

Huh... Do you know how long the leaves and shackles were?

[X9 Racer]

I couldn't take all the measurements, the front of the torque arm was 7-1/2" straight up above the front spring eye. The rear of the torque arm was 6" above the top leaf. Didn't have a chance to measure the leaves or shackles. I eyed the shackles at 6" based on the two measurements I did take.