Ok so I'm upgrading my 2dr to the Teraflex 2.5" lift. I am planing on installing the AEV geomertry brackets to correct the front drive shaft. I've seen a few post talking about front uppers and rear lowers (I think) when installing a lift. What is the benifit and why not change all the arms?

 

You want the front lowers because it will allow you to rotate the front axle to correct caster all while pushing the axle slightly forward. The same goes for the rear uppers. It will push the rear axle further from the pinch seam while correcting the pinion angle. The front uppers and rear lowers will allow you to center the axles in the fenders and fine tune pinion and caster angles, but they are not 100% necessary.

The AEV geometry brackets will correct your angles just fine,but you will lose a little ground clearance. If you plan on going with a bigger lift, the adjustable control arms make more sense but if you plan on keeping the 2.5 lift, the geometry brackets are a great alternative.

 

Read Planman's signature. Outlines the control arms really well.

 

You might want to refer to the installation instructions before you purchase the brackets. Here is a link to the one on Quadratec site AEV Geometry Correction Front Control Arm Brackets and take a look at pages 5 and 6. All is explained there about the amount of lift need to use them and how to measure.