Rednroll

Here's a complex problem for those that love doing some front end alignment math as it involves multiple stages of mods and alignment checks.

Phase 1: Pre-Lift height and alignment check (stock)

Height (measured from ground through center of wheel to bottom of fender/ measurements same on both sides)
Front = 35 3/8"
Rear= 35 3/8"

Alignment check:


Result: Toe is out.
Shop recommendation: Inner Tie rod end and drag link needs to be replaced for proper toe adjustment.

Rednroll

Phase 2: Lift additions

MODS:
- Mopar 2in Lift P/N: 77070089 (CAM Bolts not used for caster correction)
- TF Front HD adjustable Track Bar
- Spyder Trax 1.5in Wheel spacers
- RC X-Flex Front Lower Adjustable Control Arms (Used for caster correction in place of CAM bolts).

Front LCA length calculation and installed length: 22 13/16in


Height (measured from ground through center of wheel to bottom of fender/ measurements same on both sides, taken after 1K miles):
Front: 38 1/2in (3 1/8in Increase)
Rear: 38 1/4in (2 7/8in Increase)

Phase 3: Front Bumper, winch and replacement steering components

MODS:
- Synergy HD Drag Link (Adjusted to stock length 40 3/4")
- Ruff Stuff HD Tie Rod (Adjusted to stock length 58 3/8")
- Mopar Quick Disconnect front links
- AEV Front Bumper
- AEV Front Winch Plate and Tow loops
- AEV Front Skid Plate
- Badlands 12K Winch (No winch cable)

Pre-Alignment Check:


Shop Alignment adjustments:
- Tie rod adjusted for toe
- Drag link adjusted for steering wheel centering

Post-Alignment Check:


Result:
- Toe is properly aligned
- Left/Front Camber is slightly out by 3/10s of a Degree
- Caster is out on both sides

Shop recommendations:
- Camber: If pulling starts on Left, will need Camber Sleeve kit installed, adjustable ball joints.
- Caster: Increase Length of front adjustable LCA's, Adjust Right Front 1/2 turn more than Left Front LCA.

MOD
- Add 94' of synthetic rope to winch and winch fairlead.
- Remove HEAVY Speaker Box from Rear (40"x23"x19" MDF construction)
- (2) 12" Subs, 4 Amplifiers, (2) 6x9 speakers


Height Measurement: (Post bumper/winch install and Speaker box removal)
Front= 37 3/4" (2 3/8" increase)
Rear= 38 3/4" (3 3/8" increase)

Rednroll

Any thoughts on how much further I need to increase the length of my Front LCA's to correct my caster?

What am shooting for in regards to caster, isn't it 4-6 degrees for Caster?

kaptkrappy

Why is the shop recommending you replace the tie rod, it's adjustable ??


.

Rednroll

They couldn't get a good adjustment out of it, they said the inner tie rod end needed to be replaced. There was 117K miles on the stock tie rod, I could hear/feel popping sound. The inner tie rod end needed to be replaced, so instead of just doing the inner tie rod, I decided it was time to replace and upgrade to an HD tie rod.

I now edited my original post for further details in regards to their recommendation.

TheDirtman

You just have to settle on the caster as it becomes a balance of steering feel and driveline vibrations. You will likely never get back to factory caster spec lifted that high unless you go to a caster corrected axle.

Rednroll

Honestly, with the alignment currently where it is, I'm not really noticing any pull and it feels fine. I took a road trip to Northern Michigan and back this weekend right after the alignment was done, clocked about 500 highway miles round trip and it seemed fine. I was just worried that maybe with the caster where it is, if it might eventually cause front drive-shaft or any other problems where I could benefit by extending the length of the lower control arms a tad to put the caster closer to that 4-6 deg area.

I was thinking of dropping the LCA's increasing the length of the passenger side by 2.5 turns and the driver side by 2 turns, take it for a spin for a week to see how it feels and then take it back in for another alignment check to see where it's at. The shop provides free alignment checks, so it wouldn't cost me anything except for my time dropping and adjusting the LCA's.

TheDirtman

I guess you don't understand what I am talking about.

larry0071

What Dirtman is saying is that as you chase caster, you go bad on pinion angle and move closer and closer to driveline related vibration and transfer case housing failure/damage. As you go after proper driveshaft/yoke alignment to save the transfer case and driveshaft, you go further and further away from "nice driving" caster. The only way to have both is to have a caster corrected housing. So you can get your longer lower arms or you can use geometry correction brackets to flatten out and push forward the lower control arms.... but you do so while compromising the driveshaft to pinion yoke angle. Ideally, you want your 5 degrees of caster and you want your pinion yoke to driveshaft angle as close to aligned straight as possible. The more angle you add to that front U-Joint, the more U-joint whip you have feeding back as vibration and also causing stress on the transfer case housing around the area of the front output bearing.

Everyone is between a rock and a hard place in respect to that situation. I would leave your stuff alone and not chase caster if your finding the steering to be acceptable. No reason to push the issue in search of a number on an alignment machine and cause yourself heartache and pain elsewhere.

Rednroll

Absolutely NOT!!!


But now I do!!!

I guess I just always read that 5-6 deg of caster was best for lifted JK's, so that's the magic bullet I was chasing after. I wasn't sure of any associated problems of being below that where I'm currently at. It sounds like my thinking was totally backwards, where I had thought the further away from the 4-6 degree of caster you were, the more angle there was on the drive shaft/yoke alignment. So that's why I thought it would be better if I extended the arms some.

See my thinking was backwards from what you outlined?