Caster at 2.3, is it the cause of my DW?
JK Newbie
Joined: Mar 2012
Posts: 29
Likes: 0
From: San Antonio, TX
Exactly. 4.2-4.5 degrees is the range of caster you want with less than a 5" lift to save your front driveshaft.
Low caster would not be the source of DW, but it could definitely aggravate it.
In the near future, my Diagnosing Death Wobble write-up thread should be reinstated.
Here are the videos:
http://www.youtube.com/watch?v=9uQwlmlhiF4&list=UUKzIyplv3FIj1EXoFsRG0qg&index=5 http://www.youtube.com/watch?v=ii81V7XYr-k&list=UUKzIyplv3FIj1EXoFsRG0qg
Sent from my iPad using Tapatalk HD
Low caster would not be the source of DW, but it could definitely aggravate it.
In the near future, my Diagnosing Death Wobble write-up thread should be reinstated.
Here are the videos:
http://www.youtube.com/watch?v=9uQwlmlhiF4&list=UUKzIyplv3FIj1EXoFsRG0qg&index=5 http://www.youtube.com/watch?v=ii81V7XYr-k&list=UUKzIyplv3FIj1EXoFsRG0qg
Sent from my iPad using Tapatalk HD
Sorry for drifting a bit off topic here but I have a question with regard to your comment about 4.2-4.5 of caster. Would this be the same on a JKU with a ProRock 44 Unlimited since it has 10 degrees of seperation between pinion axis and ball joint axis? I will be setting mine up this weekend and was curious what I should set first, Pinion Angle or Caster? Which would you recommend more focus on and what should it be set too? The jeep will have a 4" lift with 37" Toyo tires and a 1310 front drive shaft.
Thanks, David M
JK Newbie
Joined: Apr 2011
Posts: 43
Likes: 0
From: Carlsbad, CA
We have a 3" Tereflex lift and are currently running 4.4 on the castor. We just installed an a Coast drive shaft and left the castor the same. We are now feeling a small vibration, is this normal or should we adjust the castor down?
Thread Starter
JK Enthusiast
Joined: Nov 2010
Posts: 312
Likes: 0
From: Prairieville, LA
Managed to get the jeep looked at and the front end squared up. The only things they noticed was the front lower control arms having a slight movement in the frame side. I talked with RK and they said more torque should stop the slight movement and/or a 9/16" bolt could remove the play. It is very slight.
Also the front axle was slightly off center so they re-centered the axle and torqued everything.
They saw little to no movement in any of the ball joints, but once I get it back in the morning I will go through the suspension and probably replace the frame side bolts on the lower control arms.
Also the front axle was slightly off center so they re-centered the axle and torqued everything.
They saw little to no movement in any of the ball joints, but once I get it back in the morning I will go through the suspension and probably replace the frame side bolts on the lower control arms.
Forum Tech Advisor
Joined: Jan 2008
Posts: 1,208
Likes: 11
From: Billings, MT
Planman,
Sorry for drifting a bit off topic here but I have a question with regard to your comment about 4.2-4.5 of caster. Would this be the same on a JKU with a ProRock 44 Unlimited since it has 10 degrees of seperation between pinion axis and ball joint axis? I will be setting mine up this weekend and was curious what I should set first, Pinion Angle or Caster? Which would you recommend more focus on and what should it be set too? The jeep will have a 4" lift with 37" Toyo tires and a 1310 front drive shaft.
Thanks, David M
Sorry for drifting a bit off topic here but I have a question with regard to your comment about 4.2-4.5 of caster. Would this be the same on a JKU with a ProRock 44 Unlimited since it has 10 degrees of seperation between pinion axis and ball joint axis? I will be setting mine up this weekend and was curious what I should set first, Pinion Angle or Caster? Which would you recommend more focus on and what should it be set too? The jeep will have a 4" lift with 37" Toyo tires and a 1310 front drive shaft.
Thanks, David M
JK Newbie
Joined: Jan 2008
Posts: 61
Likes: 0
From: 127.0.0.1
Also make sure it was greased. I've heard of some not being greased from the manufacturer.
JK Enthusiast
Joined: Dec 2012
Posts: 166
Likes: 0
From: Bakersfield, Ca.
Recently went to a 3.5" RK Mid-arm and in the process gave myself a case of death wobble.
Checked the trackbar since I have had trouble with it in the past, videoed it, eyeballed it, torqued it to 150lbs. Not the problem, I think.
JK Trackbar - YouTube (uploading video @ time of post, should be there by 12:30CST)
Loosened the control arms and re-torqued. Not the Problem, I think.
Tires Balanced.
Checked the toe-in and caster.
Didn't get them to adjust because I wanted to check the numbers and see exactly what I was dealing with.
Caster Left - 2.3
Right - 2.1
Toe Left - .12 (degrees)
Right - .11 (degrees)
Total - .23 (degrees)
Could the low Caster angle be to blame? I have read 200 different threads and I know it seems to be tons of guesses and theories on solving this. I battled it before and won, 9/16" bolt. It is currently sitting waiting to be aligned in the morning after I talk with the shop manager about some options. Upper and lower adjustable control arms and there is no drive shaft connected to the front end. Should I ask to go to 5 degrees caster just to be safe?
Checked the trackbar since I have had trouble with it in the past, videoed it, eyeballed it, torqued it to 150lbs. Not the problem, I think.
JK Trackbar - YouTube (uploading video @ time of post, should be there by 12:30CST)
Loosened the control arms and re-torqued. Not the Problem, I think.
Tires Balanced.
Checked the toe-in and caster.
Didn't get them to adjust because I wanted to check the numbers and see exactly what I was dealing with.
Caster Left - 2.3
Right - 2.1
Toe Left - .12 (degrees)
Right - .11 (degrees)
Total - .23 (degrees)
Could the low Caster angle be to blame? I have read 200 different threads and I know it seems to be tons of guesses and theories on solving this. I battled it before and won, 9/16" bolt. It is currently sitting waiting to be aligned in the morning after I talk with the shop manager about some options. Upper and lower adjustable control arms and there is no drive shaft connected to the front end. Should I ask to go to 5 degrees caster just to be safe?
Rich
Thread Starter
JK Enthusiast
Joined: Nov 2010
Posts: 312
Likes: 0
From: Prairieville, LA
I have a 3.5" RK mid arm system also. I had similar issues and mine was the upper front track bar bolt. I bought a hardware kit from Northridge 4x4 and changed out the track bar bolts along with the lower control arm bolts and my problems stopped. The OEM track bar bolt may be tight but there is slop. The hardware kit has a larger diameter bolt to take up the slop. The caster is not your issue and it should be between 6-7. Anything less will most likely give you flighty steering or bump steer. My caster is set at 6.5 and drives perfectly. Just my experience. Hope this helps.
Rich
I have the 9/16" bolt in the upper mount of the trackbar, torqued to 150lbs. The lower mount is the factory hardware, starting to wonder if this should be upgraded to a 9/16th bolt as well.
The bolts I have are shouldered grade 8 fine thread. Using a grade 8 nylock nut.
I also have washers (not welded) on both sides. Is this correct or a concern for slipping?
Last edited by jeepin_tiger; Jan 11, 2013 at 03:59 AM.
JK Super Freak
Joined: Oct 2009
Posts: 1,381
Likes: 1
From: East Bridgewater, MA
If you move to the 9/16 bolt on the RK joint ends you will need to drill out the joints. They are 14mm so the NR bolts won't fit. But honestly, I seriously doubt your DW is control arm related.
And don't run 6 to 7 degrees of caster. I said it earlier and Planman (the expert) agreed. Too much caster can be devastating to your driveshaft and transfer case. If you are at about 4.5 after alignment, and still have flighty steering, deal with it. Otherwise going to high on caster maybe cause some expensive repairs.
And caster is not going to be the source of DW either. It's got to be track bar, ball joint or some other issue that has been overlooked during your search.
And don't run 6 to 7 degrees of caster. I said it earlier and Planman (the expert) agreed. Too much caster can be devastating to your driveshaft and transfer case. If you are at about 4.5 after alignment, and still have flighty steering, deal with it. Otherwise going to high on caster maybe cause some expensive repairs.
And caster is not going to be the source of DW either. It's got to be track bar, ball joint or some other issue that has been overlooked during your search.
