4 link??

[FnLow69]

vibration happens with bad pinion angles. most people use four links(parallel or triangulated) for better traction/ handling, when properly set-up. In either Air ride or coil-over applications.

[PrerunnerRob]

A 4 link allows for superior axle locating, reduces unwanted movement from a suspension system, and allows for alot of adjustability. You can 4 link almost anything with a solid(one piece) axle, and also can control the characteristics of what it does upon movement.

Excellent explanation here
http://www.muddtanks.com/4LinkSuspArticle.htm

[XXL]

Originally Posted by Jcentsr6

What is the worst that can happen with bad pinon angle?

Originally Posted by FnLow69

vibration happens with bad pinion angles.

Which can lead to transmission seal failure and/or u-joint failure. "Worst case..." well, I'm picturing a dropped front u-joint that knocks out the trans seal, which leaks dry and burns up the trans, and the driveshaft drops down and bangs the hell out of the underside of the truck as it bends itself on the trailing arm xmember, then falls out in the street because the rear u-joint shatters and you have to hitchhike home But mostly like FnLow69 said... vibration.

[jlaird]

Originally Posted by XXL

Which can lead to transmission seal failure and/or u-joint failure. "Worst case..." well, I'm picturing a dropped front u-joint that knocks out the trans seal, which leaks dry and burns up the trans, and the driveshaft drops down and bangs the hell out of the underside of the truck as it bends itself on the trailing arm xmember, then falls out in the street because the rear u-joint shatters and you have to hitchhike home But mostly like FnLow69 said... vibration.

so dramatic