Rear axle angles

[MidwayJeremy]

Putting a 14 bolt under my xj this weekend....what's the proper angle it has to be keep in mind I'm welding new brackets on and won't be able to sit it down with weight on axle....

 

[GotWood]

Put jack stands under the springs and then set the angle.

 

[mcutler]

I have always set the weight on the new perches without mishap. Once all the weight is on, I use a floor jack under the pinion snout to move it to the desired angle, then weld it up.

Sent from my PB99400 using Tapatalk

 

[MidwayJeremy]

So when it sitting normal ready to drive the angle of the pinion should be straight with driveshaft?

Also my jeep doesn't have a front axle so its on that jack stand lift.
I need to see what the angle would be if ya jacked up rear of Cherokee with 14 bolt under it and took a pic

 

[MidwayJeremy]

Also I'm sure it matters but I will have a flipped Dana 300 under it as well

 

[GotWood]

You need to set the drive train first then get your angles.

 

[getstucksome]

So when it sitting normal ready to drive the angle of the pinion should be straight with driveshaft?

Also my jeep doesn't have a front axle so its on that jack stand lift.
I need to see what the angle would be if ya jacked up rear of Cherokee with 14 bolt under it and took a pic

That depends on what style driveshaft you have.

http://www.pirate4x4.com/tech/billavista/PR-shaft/index2.html

That article should explain which angles for which driveshafts to use.

edit: just reread first post, I'd say you need the weight on the rear axle to get it all setup correctly

 

[Tom@Hilltop_Machine]

If your using new springs then they will settle in a few months and your angle will change. I usually find the angle I need then drop it about 2 degrees to compensate for the upcoming drop.

 

[MidwayJeremy]

If its off a couple degrees will that matter?

 

[OnlyOneDR]

If its off a couple degrees will that matter?

At running height, yes. The angles must match and the yokes in-phase to cancel out the oscillations that occur when it rotates. Best to use an angle finder or a bevel square and a plumb bob to do this.

 

[GCncsuHD]

So when it sitting normal ready to drive the angle of the pinion should be straight with driveshaft?
That depends...If you have a regular driveshaft with a u-joint at the transfer case, and a u-joint at the axle, you want the angles to match, so that it will cancel the vibrations out. Your pinion should be parallel to the transfercase output, not pointing at it.

If its off a couple degrees will that matter?

A couple degrees isn't much, but if you can, err on the low side on the pinion. It is desirable to set the pinion up to a couple degrees lower than the transfer case angle, that way when you accelerate, it will twist the pinion upwards into the correct angle. If you had it too high, when you accelerate it would twist too high and cause vibrations then.