Cal Trac Bar Installation In Tarrant
Description
Form popularity
FAQ
Either way, you are ultimately looking for pinion angles of 1-2 degrees above the drive shaft angle in the front and 1-2 below drive shaft angle in the back. Theoretically zero is perfect, but the offset allows for axle wrap (twist) under power.
We suggest a pinion angle to be between -2 to -4 degrees when used with CalTracs.
Pinion angle is the key. Once you have the traction bars installed you'll want you pinion angle to be negative 2.5 to negative 3-5 degrees.
The pivot at the front leaf eyelet then forces the pin riding on top of the springs downward into the spring pack itself. This downward force of the pin on the leaf springs causes down force on the entire axle assembly and pushes your tires down onto the pavement/dirt.
Ideally, both driveshaft-operating angles will be 1 to 3 degrees. Anything over 3 degrees at the rear axle will shorten your universal joint's life and could create vibration. If your angle is larger than 3 degrees, you must make sure not to exceed the max driveshaft RPM as shown on this Spicer table.
Most driveline companies recommend operating angles of 3° or less for maximum u-joint life. There should be a minimum of ½° to allow the needles to rotate. The higher the operating angle, the more likely your vehicle will develop a vibration at high driveshaft speeds.
