Hey all,

This thread is really going to show my ingnorance on this but I had a question regarding SAS. What are the pros and cons of using a 4 link over a 2 link (I guess it called a 2 link?)? Seems that every coiled SAS done on a Toyota I've seen has been a 4 link. Now this link shows a Xterra coiled SAS kit for sale that has just 2 links:

http://www.xterraownersclub.com/revi...ini_sas01.html

Are there any benefits to using a 4 link over a 2 link? With the 2 link it seems that the front 3rd and driveshaft will remain at the same angle in relation to each other, no matter how much flex is being excerted on the rest of the suspension. Is this less stress on the u joint? Would the pinion get enough lubrication with this set up?

Would a 4 link provide better flex?

Sorry for the stupid question, but just something I was wondering about.

Thanks all.
Daniel

 

the "2 link" is more commonly refered to as radius arms

FJ80s, and the "long-arm" jeep lifts all use radius arms.

the difference isnt really in flex, its in the handling of the vehicle and suspension.

4links are generally better because of the way they handle and maintain the caster of the axle, as well as redundancy (if you trash one of the links, you still have a chance of driving out, whereas with radius arms, if you trash one, you are done)

in the front of a rig, with the engine and steering components, 4 links are hard to fit. most people go with a 3 link (2 lowers, one upper) and a panard. it has similar performance to a 4-link, but is much easier to fit

 

this is one of those things I never understood either. suspension can be so baffling. I still don't know what a panhard bar is.

 

Panhard bar's only job is to keep the axle centered under the vehicle.

The Calmini is a radius arm with panhard. In essence its a 3 link.

Most of these dual triangulated 4 link setups you see on the web don't need a panhard because the triangulation locates the axle.

Our 4Runners need the panhard because the rear links aren't triangulated (making it a 5 link).

 

I have a great article I found in JP about suspension systems. I'm planning to scan in the pics and article and post them up.

 

Thanks all! So, is a 3 or 4 link more durable? Seems like under extreme flex, radius arms would twist like a torsion bar. With links, a person could use those orbit eye type of mounts to keep this from happening, right?

Also, what's a heim?

 

Heim aka Rod End...

http://www.polyperformance.com/shop/home.php?cat=154

 

Oh, ok. Thanks!

When people are counting the number of links on a vehicle, do they usually include the panhard bar? Do they say 4 link, or 3 link and a panhard?

Thanks! Sorry for the stupid question.

 

Seems theres no set standard (not that I've seen anyway). Some folks say "# link with panhard", some call every rod that connects to the axle a link.

BTW, another name for a panhard bar is a trackbar (that's what they call them on Jeeps from what I've gathered)

 

Oh, I forgot about the trackbar! Now that you mention it, they talk a lot about trackbar adjustments on NASCAR.

 

Another question: Is a Johny joint pretty much the same thing as a Heim except that it is rebuildable?

Mods, if you want to move this to the newbie section, thats cool with me. These are newbie questions, I think.

 

yes its pretty much the same thing. The johnny joint is better for a number of reasons. Rebuildable, made for off-road, tougher races, and tougher material.

 

ah, ok thanks.