I need help with pinion angles

[EnlistedManche]

Hey all, Currently i am having a buddy weld up my truss and my leaf spring brackets on my 8.8. But i've reached a delma. When i put the 8.8 in i will be lifting the truck to about 6.5 inchs from the 4.5 I'm at now with SOA and stock springs and will be adding a SYE. so i have no idea what angle my pinion yoke should be does any one have a rough estimate of what it should be or any one with 6.5 inchs know what their pinion angle is? thanks

[Tj1]

Cherokees and Wranglers with SYE typically shoot for 1-3 degrees under 0, maybe more to help with small amounts of spring wrap.  Maybe someone can confirm this.

[Eagle]

When you add the SYE, will you be adding a double cardan joint at the transfer carse output (like the front driveshaft), or are you going to stay with a single u-joint at each end of the driveshaft?

[EnlistedManche]

yes double cardan

[EnlistedManche]

trying to guesstimate my pinion angle and was curious to what people around 6.5-8 inchs of lift have their angles at. i will be running a slip yoke eliminator and a double cardan driveshaft.

[Rockfrog]

Pinion angle will be dependent on how it all goes together, kinda something that needs to be measured at the time of install.

You want the pinion to point directly at the transfer case out put with a drop of 2 degrees max for pinion rise under power.

If you measure the expected axle position you should be able to estimate approximate angles from there.

It should give you enough ballpark to have the truss tacked on. Or hold off until the axle is actually mounted to be sure.

 

Sent from my SGH-I337M using Tapatalk

[Eagle]

trying to guesstimate my pinion angle and was curious to what people around 6.5-8 inchs of lift have their angles at. i will be running a slip yoke eliminator and a double cardan driveshaft.

 

With a double cardan at the transfer case end, the pinion angle should be zero at the differential yoke.

[Rockfrog]

You need to correct for pinion climb under power ... Generally this will be 1-2 degrees down from zero in the rear, and 1-2 degrees up in the front. It is less important to correct for it in the front with a link suspension, but in the rear, a leaf suspension will always have a little climb under load.

 

 

Sent from my SGH-I337M using Tapatalk

[Eagle]

You need to correct for pinion climb under power ... Generally this will be 1-2 degrees down from zero in the rear, and 1-2 degrees up in the front. It is less important to correct for it in the front with a link suspension, but in the rear, a leaf suspension will always have a little climb under load.

 

How do you define "up" with a double cardan joint?

[Rockfrog]

You don't do anything at the DC joint. You rotate the pinion, at the other end of the driveshaft ... down for the rear, up for the front. As in up, and down according to the laws of gravity.

If you set pinion angle at exactly zero degrees (pointing straight at the transfer case outputs) ... The rear pinion (at the axle) will climb, go up, from the ground ... a couple degrees due to spring wrap. As a result you will still get vibrations thinking you did it all right. General rule is to correct by adjusting 1-2 degrees. So since the rear pinion climbs (goes up, from the ground, towards the sky) under load, and the front pinion dives (goes down, towards the ground, away from the sky) we add a slight offset accordingly eliminating the cause of the vibration where it's actually needed. Under load, when the driveshaft is spinning.

 

 

Sent from my SGH-I337M using Tapatalk

[Jackrabbit41]

My Long bed pinion angle on my 8.8 is likr 8 or 9

[A-man930]

Subscribing