Quick caster question.

[2LO4ME]

Will be installling a 6" Pure Performance lift soon on a 2010 3500.

I've read on here multiple times that front driveshaft vibration is common. Some are fixing this by pointing the alignment cams on the lower control arms to the rear (if memory serves me). Others need to get the shaft re-balanced or lengthened.

But if you point the cams to the rear won't this throw the alignment/caster off? Which can cause wandering.

I'm assuming its more important to keep the cams in their proper location after an alignment, and address the driveshaft itself if I get vibration?

[strtlegal]

Yep I would keep your cams up or forward. On a 4 link this can cause the u-joints to bind, however a good setup should keep these angles in check. On my truck with Thuren arms I never got an vibration even all the way forward.

Good luck

[domedyou]

Originally Posted by 2LO4ME

Will be installling a 6" Pure Performance lift soon on a 2010 3500.

I've read on here multiple times that front driveshaft vibration is common. Some are fixing this by pointing the alignment cams on the lower control arms to the rear (if memory serves me). Others need to get the shaft re-balanced or lengthened.

But if you point the cams to the rear won't this throw the alignment/caster off? Which can cause wandering.

I'm assuming its more important to keep the cams in their proper location after an alignment, and address the driveshaft itself if I get vibration?

I have pure long arms and I have delt with the caster issues.

Are you getting long arms? I am not familiar with their short arms.

On the long arms the end that goes into the axle housing is threaded. So that kinda makes the cam bolt not really do what they are supposed to do until you get the arms the correct length.

I installed my arms and eyeballed the angle of the pinion yoke and drive line. I put it where I though was right. Took the truck to an alignment shop and the caster was set at 1.2. So I pulled the cam bolts out and unscrewed the bottom heim and I repeated till I was close to 4.5. (the cam bolts only change caster by 2 deg from forward to back) then I used the cam bolts to set it to 4.5. Went for a drive and I have driveline hum real bad when I was going over 60. So I adjusted the caster back to 3.5 and now I have no more hum.

I am going to install an index ring when I do my trans and set my caster back to 4.5 and see if my driveline hum is gone.

If you have any questions please feel free to pm me. I just went through all this very recently.

[Skyd Ram]

Originally Posted by 2LO4ME

Will be installling a 6" Pure Performance lift soon on a 2010 3500.

I've read on here multiple times that front driveshaft vibration is common. Some are fixing this by pointing the alignment cams on the lower control arms to the rear (if memory serves me). Others need to get the shaft re-balanced or lengthened.

But if you point the cams to the rear won't this throw the alignment/caster off? Which can cause wandering.

I'm assuming its more important to keep the cams in their proper location after an alignment, and address the driveshaft itself if I get vibration?

You are correct,
Pointing the cams toward the back of the truck will decrease the pinion angle (less driveshaft angle) but it will also decrease the caster. Once caster gets much below 3.5 the truck will tend to wander and not have a strong return to center feel. If the caster get too low it can also contribute to death wobble.

In your case you may want to do what Domedyou said and try to get the caster around 4 degrees with the cams straight up. That way you will have some adjustment in both directions to play with caster in the future if needed.

[2LO4ME]

Domedyou, I will be running the short arms, which have the threaded heim on one end of each arm.

Thanks for the input everyone, I really appreciate it. Just wanted to make sure I was thinking correctly.