Caster help ASAP please. Headed out in the morning.

RUBEERCON

New member
Thanks in advance!

I'm googled out and vids are not helping much either.

2015 JKU auto
Used to perform without issues, now, flighty and vibrates at 60mph

4" Rancho sport
Tossed correction brackets and added Rancho Adj front lowers only. Rear control arms stock for now.

Set lowers at 23" and the pinion flange shows zero deg. Instantly acquired bump steer that I did not have. Correction brackets were doing the job but I bent a control arm and it sent me on a path.

I Just added Olivers 1310 driveshafts front and rear.

What deg should the pinion flange read with my current set up?

7deg to equal 4.5 caster? I just can't comprehend where to find the 2 readings that equal the final goal.

Thanks for any help, I know the info is out there but I just can't simplify it. I need to be loading the jeep for the SMORR turkey run.

Steve
 
J

JKDream

Guest
Stock or aftermarket housing? They are measures in seperation; meaning if you have two degrees of pinion angle upwards, you have four degrees of caster on a stock housing.

Sent from my ONEPLUS A3000 using WAYALIFE mobile app
 

RUBEERCON

New member
Shortened lower arms to 22-5/8 from 23". Pinion flange shows 4deg and front Diff housing round flat spot shows 92deg.

Lower arms are maxed out will not get any shorter. Bump steer is a lot better but the vibration at 60-80 is still there. May vibrate at lower speeds but it's hard to tell with my rock trashed tires.

If I trailer will it hurt anything to low speed off road? I don't think I can get this vibration out on my own.

Steve
 

RUBEERCON

New member
Measured rear axle with socket setting under u joint cap. It reads 10deg and Carden driveshaft reads 9 deg
 
Last edited:

Speedy_RCW

Hooked
Shortened lower arms to 22-5/8 from 23". Pinion flange shows 4deg and front Diff housing round flat spot shows 92deg.

Lower arms are maxed out will not get any shorter. Bump steer is a lot better but the vibration at 60-80 is still there. May vibrate at lower speeds but it's hard to tell with my rock trashed tires.

If I trailer will it hurt anything to low speed off road? I don't think I can get this vibration out on my own.

Steve

If your pinion is pointing up 4 degrees that only gives you 2 degrees caster. You need to extend your lowers to increase caster. That should help with the flighty steering. You may need to find a happy medium between caster and pinion angle. When I had a stock housing I was running 3 degrees but it was manageable.


Sent from my iPhone using WAYALIFE mobile app
 

RUBEERCON

New member
Doesn't extending out the arms lower the pinion back towards zero on degree finder? If so that takes me back to the 23" range where the steering seemed worse. Am I going the wrong way, does the pinion snout need to go towards the ground? I would think that it needs to align with driveshaft angle. I'm out of arm adjustment with only having adjustable lowers and stock uppers.

Sorry guys this is a head banger for me. I'm going to learn from trial and error until I get this vibration gone!
 

BaddestCross

Active Member
Aside from caster, you have to get the pinion aimed at the transfer case as much as possible since you've got the new 1310 driveshaft. A happy medium needs to be found. If it's angled down from the pinion too much that may be the cause of the vibration.

--
Build Thread - Adventures of Fiona - https://wayalife.com/showthread.php?t=47407
 

jeeeep

Hooked
Shortened lower arms to 22-5/8 from 23". Pinion flange shows 4deg and front Diff housing round flat spot shows 92deg.

Lower arms are maxed out will not get any shorter. Bump steer is a lot better but the vibration at 60-80 is still there. May vibrate at lower speeds but it's hard to tell with my rock trashed tires.

If I trailer will it hurt anything to low speed off road? I don't think I can get this vibration out on my own.

Steve

set your caster as close to stock and call it good - round flat spot at 92*

may want to extend the arms a degree a hair and see if it improves. getting somewhere between 88 and 92 should help the vibration so long as it isn't your tires causing it.

you took into account the levelness of the surface the Jeep is sitting on?

With that much lift you are going to have bump steer unless you added a drag link flip kit
 

WJCO

Meme King
set your caster as close to stock and call it good - round flat spot at 92*

may want to extend the arms a degree a hair and see if it improves. getting somewhere between 88 and 92 should help the vibration so long as it isn't your tires causing it.

you took into account the levelness of the surface the Jeep is sitting on?

With that much lift you are going to have bump steer unless you added a drag link flip kit

Bingo to all. ^

Drag link flip will likely cure your bump steer. Post pictures of your axle, your steering, and the control arms. If you're using correction brackets and adjustable arms, you may have too much caster which will definitely cause a driveline vibration.
 

JKbrick

Active Member
I thought on the front you need to worry about your caster not your pinion angle, but on the rear just point your pinion straight in line with your driveshaft. Don’t forget if you do a flip drag link to have 3” of bump stop


Sent from my iPad using WAYALIFE mobile app
 

RUBEERCON

New member
Thanks all!

Doing the work on my garage floor, it's nice and level.

Correction brackets were removed when I installed lower arms. Lower front adj arms only. Arms are maxed out, pinion is pointed at transfer case. I can lengthen them and go back towards 88deg just to see if it helps any.

Currently at 92 deg and the vibration is the major issue. Bump steer is tolerable right now.

I have a stinky fab AL tie rod, steer smart no drill top mount drag link with attenuater and steer smart track bar and raised bracket all in boxes. Waiting to install, planning on welding my gussets, truss and adding ball joints soon., the adding the steering upgrades.

Looks like I'll be buying 3 more pairs of adj control arms to complete the lift. Maybe some shorter springs...

I bought the Rubicon and chose the 4" lift based off of a rebate before I did any research. Honestly it was a great lift overall for 2 years but the front driveshaft started failing and sent me chasing parts and solutions.

I took my time installing the driveshafts but I can't help to wonder if the vibration is from the new shafts. Installing the rear yoke was nerve racking after reading about the crush sleeve issues. I ran the nut on with an impact until the yoke quit moving around and then finished off with a torque wrench to 160ft pounds.
 

jeeeep

Hooked
Thanks all!

Doing the work on my garage floor, it's nice and level.

Correction brackets were removed when I installed lower arms. Lower front adj arms only. Arms are maxed out, pinion is pointed at transfer case. I can lengthen them and go back towards 88deg just to see if it helps any.

Currently at 92 deg and the vibration is the major issue. Bump steer is tolerable right now.

I have a stinky fab AL tie rod, steer smart no drill top mount drag link with attenuater and steer smart track bar and raised bracket all in boxes. Waiting to install, planning on welding my gussets, truss and adding ball joints soon., the adding the steering upgrades.

Looks like I'll be buying 3 more pairs of adj control arms to complete the lift. Maybe some shorter springs...

I bought the Rubicon and chose the 4" lift based off of a rebate before I did any research. Honestly it was a great lift overall for 2 years but the front driveshaft started failing and sent me chasing parts and solutions.

I took my time installing the driveshafts but I can't help to wonder if the vibration is from the new shafts. Installing the rear yoke was nerve racking after reading about the crush sleeve issues. I ran the nut on with an impact until the yoke quit moving around and then finished off with a torque wrench to 160ft pounds.

did either drive shaft separate before you installed them? they are indexed when balanced.

if they separate and not put back together on the index marks it will throw them out of balance
 

RUBEERCON

New member
Good point. Yes they were.

I read that step after the fact and called the dealer, they said the yokes could go either way. Every part was color coded except for the yokes and mating pieces.
 
Top Bottom