Fitting 285 Tires with LR UCAs (Adjusting Caster)

[Bicepus Maximus]

OEM caster adjustment is done by off-setting the Lower Control Arm (see attached) by moving it forward toward the front, or back away from the front of the vehicle using cam bolts and nuts.

Light Racing Upper Control Arms have the ability to adjust caster by off-setting the UCA ball joint. So if you run LR UCAs, you have two areas where caster can be adjusted.

My LR UCA ball joint is in the D position on the installation diagram (see attached). Which is actually adding positive camber due to the geometry of the UCA. Now if you read step 8 in the installation diagram, you'll see that the LR UCA is designed to bring the caster back into spec in position D for most 2 - 3" lifts.

What this means:
- Installing a 2 - 3" lift with a stock UCA (before the alignment is done): caster is less positive than stock.
- In this scenario, when the alignment is done, the caster is adjusted back to more positive by moving the LCA more forward, toward the front of the vehicle.
- Now if the lift is installed along with a LR UCA, and the UCA's ball joint is set to the D position, the caster remains within (or close to) spec. The alignment will not require much of a caster adjustment.

What this means to people running 285 tires and 1.25" wheel spacers (my current situation):
- If you have LR UCAs set in position D and your caster is within spec, and your tire is rubbing on the mud flap or the body mount; you should be able set the UCA ball joint to position G (back to where the stock UCAs would have the ball joint), and have an alignment done to move the LCA forward (away from the body mount) to bring the caster back to spec.

My tire is much closer to the mud flap and the body mount than it is to the front fender lining. I won't be able to do this adjustment until after this weekend. I'll report back.

In the mean time, I'm curious if anyone running LR UCAs have them set to position G? What tires are you running? Do you have wheel spacers? Any rubbing?

Sorry for the novel. Hopefully it's more helpful than confusing.

The following are attached for reference:
Caster diagram (for reference)
OEM LCA caster adjustment
LR UCA installation diagram

 

[KodeRush]

I have LR UCA on D position. I also have 285/70/R17 on 9" wide rim(offset -12mm) and 1.25" spacer. The caster is around 3.5 degrees. I has chopped the body mount and taken the mud flaps off, so no rubbing at all.

You didn't mention your rim offset, but I think if you took off the mud flaps, you might be able to get rid of rubbing by just adjusting caster(up to 4.0) and with UCA in D position.

 

[Bicepus Maximus]

Thanks for the feedback, [MENTION=88849]KodeRush[/MENTION].

I'm on stock wheels. And I'd rather not remove the mud flap. We'll see.

I'll change the position of the UCA ball joint to bring it back to stock and then adjust camber as far forward as possible. Hoping the only thing I'll have to do after that is pull the fender lining forward.

 

[jbstrd]

You didn't mention your rim offset, but I think if you took off the mud flaps, you might be able to get rid of rubbing by just adjusting caster(up to 4.0) and with UCA in D position.

This is what I am doing. I have 17x9 wheels with -12mm offset with no spacers wrapped with 285/70/17. I have zero rubbing with the caster set to +4 degrees and the mud flap removed.

 

[barryhiram]

I too have LR UCA on D position with 285/70/17 on stock rims, and no spacers. Caster was set to +4 degrees. Had slight rub with front fender liner, did inner fender liner mod with a little heat gun action, no more rub. Have plenty of clearance to body mount and mud flap.

 

[Addicted]

Did the Light Racing UCAs come with the ball joint already installed or do you have to do that yourself?

 

[Bicepus Maximus]

Comes disassembled.

 

[Addicted]

Comes disassembled.

Thank you.

 

[Addicted]

I posted this in a different thread but Im hoping you guys could give me some advice. Yesterday I wrapped up putting a Toytec Boss lift on my wife's 2013 TE. I also installed LR UCAs on the "D" setting. she's running 285/70R 17s on TRD RW wheels. At the time I slid the camber adjustment all the way out and snugged it up just for the ride to the alignment shop. I dropped the truck off this morning and gave the tech the LR UCA instruction and told him I wanted +4 degrees of caster and +.1 of camber. I picked up a little while ago and he said he got it as close as he could. Here's my numbers. Camber = .3 degrees right and left. Caster = 2.7 Left and 3.1 Right. He said he maxed out the adjustment on the LCAs and that was the best he could do. I took his word for it and drove home. Im still rubbing in the rear a little bit but I figured I'll deal with it. But here's the thing. I just looked at the upper ball joint and the tech didn't touch it AT ALL. Both sides are slid all the way out just like I left them. So Im guessing he couldn't get any more caster because it was screwing with the camber. But he didn't even bother to adjust the camber by using the adjustment in the LR UCAs. WTF? Im pretty irritated and I don't want to even take it back there. So here's my question. Could I just move the ball joint to the "C" position? That should give me another + 1 degree which would give me +3.7 Left and 4.1 Right. By my thinking that should give me a little more clearance by moving the tire forward in the wheel well and help with the rubbing. Or am I wrong? Also, how would that effect my camber, if at all? And help or advice is appreciated. Thanks.

 

[Scott@Hightech]

%95 the ball joints should be left in the "D" position. this will give the best clearance while still being able to obtain +4 deg of caster. I have on a few trucks Maxed out caster via the LCA adjustments and ran the ball joint in the "E" position. basically this moved the entire assembly forward. Which creates more room in the back side but you would nbeed major trimming or an aftermarket front bumper. This also reduced the maximum caster to something closer to 3 degrees. which is less idea. but fi you need the room its an opition.

 

[Addicted]

Well that's the problem. He never used the upper ball joint to adjust the camber. So basically he got as much caster as he could using the cams on the LCAs but he got to the point where he couldn't get any more caster without starting to screw up the camber. Im pretty sure he could have gotten +4 if he would have used the adjustment of the Light Racing UCAs. In any case, the truck drives fine. I wanted as much caster as possible so I wouldn't have to remove the mud flaps but I just went ahead and trimmed them and moved the liner forward in the front. Its all good now. No rubbing front or rear. All I had to do with the mud flaps is cut out the hump in the center. Its barely even noticeable. Here's the flap with the "hump" removed.

Here's from the back side.

And here's with the wheels turned at its closest point.

 

[montana_jeepn]

OEM caster adjustment is done by off-setting the Lower Control Arm (see attached) by moving it forward toward the front, or back away from the front of the vehicle using cam bolts and nuts.

Light Racing Upper Control Arms have the ability to adjust caster by off-setting the UCA ball joint. So if you run LR UCAs, you have two areas where caster can be adjusted.

My LR UCA ball joint is in the D position on the installation diagram (see attached). Which is actually adding positive camber due to the geometry of the UCA. Now if you read step 8 in the installation diagram, you'll see that the LR UCA is designed to bring the caster back into spec in position D for most 2 - 3" lifts.

What this means:
- Installing a 2 - 3" lift with a stock UCA (before the alignment is done): caster is less positive than stock.
- In this scenario, when the alignment is done, the caster is adjusted back to more positive by moving the LCA more forward, toward the front of the vehicle.
- Now if the lift is installed along with a LR UCA, and the UCA's ball joint is set to the D position, the caster remains within (or close to) spec. The alignment will not require much of a caster adjustment.

What this means to people running 285 tires and 1.25" wheel spacers (my current situation):
- If you have LR UCAs set in position D and your caster is within spec, and your tire is rubbing on the mud flap or the body mount; you should be able set the UCA ball joint to position G (back to where the stock UCAs would have the ball joint), and have an alignment done to move the LCA forward (away from the body mount) to bring the caster back to spec.

My tire is much closer to the mud flap and the body mount than it is to the front fender lining. I won't be able to do this adjustment until after this weekend. I'll report back.

In the mean time, I'm curious if anyone running LR UCAs have them set to position G? What tires are you running? Do you have wheel spacers? Any rubbing?

Sorry for the novel. Hopefully it's more helpful than confusing.

The following are attached for reference:
Caster diagram (for reference)
OEM LCA caster adjustment
LR UCA installation diagram

How did you make out? I have been running position "D", but once I put my spacers on they are still extremely rubbing even after I took off the mud flaps. I currently have both sides set to "G" and will be taking it in for an alignment tomorrow. Anyone else use "G"? I can see I may have to do some trimming on the front bumper possibly after they adjust the LCAs.

 

[montana_jeepn]

Well, I took it to Firestone...they gave me a little flack for my "custom suspension" but ended up helping me out anyways. I took it in there on position "G" and they were able to get everything in spec except my castor. It doesn't really handle that bad, but it is just temporary until I upgrade the suspension so I am just a little higher to get rid of the rubbing. While I am still getting rubbing sometimes when I turn, I won't be tearing my flares off.

 

[jdtaylor42]

Reviving this thread because I installed Toytec Ultimate 3" lift with LR UCA, 285/70R17 Duratracs, stock wheels and wheel spacers. I was not able to get the alignment done immediately and it was rubbing bad against mud flap and body mount so I adjusted to setting "G" and removed the mud flaps.

I then took it to Toyota dealership for alignment and they were only able to get 2 degrees of caster out of LCA with UCA in "G" and the camber is still not great. With this setup it still rubs on body mount in reverse at full lock.

I plan to take it somewhere else for a second go at the alignment but I am wondering if I should swap back to "D" setting before I take it in? I plan to wheel pretty heavy with this rig and I don't want to worry about rubbing in reverse or when flexing. Any opinions or suggestions?

 

[montana_jeepn]

Reviving this thread because I installed Toytec Ultimate 3" lift with LR UCA, 285/70R17 Duratracs, stock wheels and wheel spacers. I was not able to get the alignment done immediately and it was rubbing bad against mud flap and body mount so I adjusted to setting "G" and removed the mud flaps.



I then took it to Toyota dealership for alignment and they were only able to get 2 degrees of caster out of LCA with UCA in "G" and the camber is still not great. With this setup it still rubs on body mount in reverse at full lock.



I plan to take it somewhere else for a second go at the alignment but I am wondering if I should swap back to "D" setting before I take it in? I plan to wheel pretty heavy with this rig and I don't want to worry about rubbing in reverse or when flexing. Any opinions or suggestions?

I put mine back to "D" and had a Firestone I trust do the alignment. It handles well for being lifted now, but I still rub occasionally......just on pavement. I'd say do a body lift or start trimming......maybe both. In "G" she handled pretty horrible.

That is one thing I really miss about my Jeep.....it was so much easier to put on larger tires.

Good luck!

 

[jdtaylor42]

I put mine back to "D" and had a Firestone I trust do the alignment. It handles well for being lifted now, but I still rub occasionally......just on pavement. I'd say do a body lift or start trimming......maybe both. In "G" she handled pretty horrible.

That is one thing I really miss about my Jeep.....it was so much easier to put on larger tires.

Good luck!

Thanks. I will move it back to "D" and take it in to see what they can do.

I may end up doing the body mount chop just so I don't have to worry about ever rubbing. Now I just need to find a thread about doing the chop...

 

[Scott@Hightech]

Thanks. I will move it back to "D" and take it in to see what they can do.

I may end up doing the body mount chop just so I don't have to worry about ever rubbing. Now I just need to find a thread about doing the chop...

Put it in the D position and slide it almost all the way out, this is a goo starting point. Also make sure that the flat side with the letters SPC is pointed outwards.

then let them align it and ask them for 4* of caster and around 0* camber