Details on howto Adjust SPC Light Racing Upper Control Arms Yourself the Easy Way!

My normal alignment guy is on vacation so I am having to use someone else who has never messed with SPC UCA's so I did a little write up for him. I haven't seen anything like this posted before so I figured I would share. It might help some folks out so they don't resort to pry bars, etc...

My goal is:

Caster: between +3.60 and +3.80
Camber: -0.03
Toe: 0.00

If your is different the adjust the howto to your specs




- Take starting Camber, Caster, Toe measurements and write them down

- First set Caster using only the Lower Control Arm Cams to:

Left: +3.60 (no higher than +3.80)
Right: Match the left side


- If you can not get enough Positive Caster, set the Lower Control Arms Cams to Max Caster

- To adjust Caster using the Upper Control Arms...

- Place floor jack under the Front Lift Point in the center of the truck

- Raise the truck enough to take the load off of the Upper Control Arms

- Use a breaker bar and 32mm socket to remove the nut and washer on the top of Ball Joint

- Rotate Star Plate on the Ball Joint to Position “C” as shown on the included instruction sheet

- Use the floor jack to lift and lower the truck to get the Ball Joint back in place.

NOTE: the Ball Joint must be turned facing the right way so that it fits into the groove/track on the bottom of the Upper Control Arm

- Once the Ball Joint is in place, replace the washer on the Ball Joint

- Use a Torque Wrench and 32mm socket to tighten the nut on the top of Ball Joint to 150 lb-ft



- If you have too much positive Caster, set the Lower Control Arms Cams to Max Caster

- To adjust Caster using the Upper Control Arms...

- Place floor jack under the Front Lift Point in the center of the truck

- Raise the truck enough to take the load off of the Upper Control Arms

- Use a breaker bar and 32mm socket to remove the nut and washer on the top of Ball Joint

- Rotate Star Plate on the Ball Joint to Position “E” as shown on the included instruction sheet

- Use the floor jack to lift and lower the truck to get the Ball Joint back in place.

NOTE: the Ball Joint must be turned facing the right way so that it fits into the groove/track on the bottom of the Upper Control Arm

- Once the Ball Joint is in place, replace the washer on the Ball Joint

- Use a Torque Wrench and 32mm socket to tighten the nut on the top of Ball Joint to 150 lb-ft


- Fine tune Caster using Lower Control Arm Cams to:

Left: +3.60 (no higher than 3.8)

Right: Match the left side


- If Caster is set proceed to set Camber

- Measure Camber, Write down the Camber measurement

- We want Camber set at:

Left: -0.03
Right: -0.03

- If the Camber needs to be adjusted, Do Not Touch the Lower Control Arm Cams, only use the Upper Control Arm adjustments to set the Camber


- To set the Camber...

- Use a marker to mark the current position of the washer under the nut on the Ball Joint in relation to the Upper Control Arm

- Place floor jack under the Front Lift Point in the center of the truck

- Raise the truck enough to take the load off of the Upper Control Arms

- Use a breaker bar and 32mm socket to slightly loosen the nut on the top of Ball Joint just enough so it can slide back and forth, do not remove the nut


- To add more positive Camber while watching the ball joint, raise the truck using the floor jack, when the Ball Joint has slide the proper amount towards the outside of the truck tighten the top nut on the Ball Joint


- To add more negative Camber while watching the ball joint, lower the truck using the floor jack, when the Ball Joint has slide the proper amount towards the engine of the truck tighten the top nut on the Ball Joint

- Lower the truck

- Roll the truck to reset the suspension

- Measure the Camber

- If desired Camber has been achieved, use a Torque Wrench and 32mm socket to tighten the nut on the top of Ball Joint to 150 lb-ft


- If desired Camber has not achieved repeat the process above to add more negative or positive Camber


- Once Camber is set, set Toe to:

Left: 0.00
Right:0.00


- Once Toe is set, take measurements of Caster, Camber, Toe and write them down

- If only minor adjustments need to be made you can use the Lower Control Arm cams to make adjustments


- If major adjustments need to be made, make adjustments using the Upper Control Arm
Camber and Caster adjustments as detailed above


- Once Caster, Camber, and Toe are at the correct measurements, drive the truck

- Sometimes when the Caster is equal on both sides the truck pulls to the right. If this happens try slightly increasing the amount of positive Caster on the right side

- Drive the truck, if it tracks strait, drives good and does not rub at full tilt when turning or backing up we are all set!







If anyone has anything to add let me know

 

@toku58 I respect your opinion and advice on the advantages of the SPC UCAs over its competitors and I'm curious about your thoughts on the write-up above.

 

This write up is in regards to what the OP wants to achieve.
(Not what I would do, but it's his truck.)
The great thing about the SPC is that you can have a wide range of settings with very little effort.
If you set it as in the first video I posted then all you need to do is slide the UCA ball joints to achieve the correct Camber. But at setting "G" you would be able to get about 2-2.25* of Caster. At setting "F" you can get about 2.25-2.5* of Caster.

https://youtu.be/f2YhnldfI50
https://youtu.be/huMztKaHsUE

 

In the real world, with 100lbs of tire and wheel and 50lb spindles installed its not as easy as sliding things around like in that video so you have to use the flex of the suspension to slide the ball joints. If you know a better way please let me know, it would save me some time

FYI "G" with LCA cams centered would put you at approx. 0.00 Caster or OEM which equals tire rub
FYI "F" with LCA cams centered would put you at approx. +0.25 Caster which equals tire rub

on "D" with LCA Caster maxed out I get +3.6 on the Left and +3.9 on the right, not much room to work with the LCA cams for fine tuning to keep tires moved forward, hence possibly need to adjust ball joint settings.

 

Even if she's talking about a 3rd gen. We share the same cab and frame specs.

https://youtu.be/QqgIMEb705I

 

3rd gen have an inch more clearance

 

The additional inch comes from the Coils of the suspension. If you took the coils off of a 3rd gen and put it on a 2nd gen it would be an inch higher.

But we are not talking about lifts.
We are talking about alignment and the SPC's, and cab mount clearance.
Your understanding of the additional Caster is wrong.
Setting "D" adds Caster. (Which you Do NOT want)
The way it accomplishes this is by moving the Upper Ball joint towards the Cab Mount. Thus reducing the clearance of the tire and Cab Mount. (NOT GOOD!!)

To have maximum clearance from the Cab Mount. You want to move the LCA's as far forward as possible and use the SPC's to achieve the correct spec's of CASTER and CAMBER.
Specified CASTER on the 2nd gen is 1.3*-2.8* of caster.
To go above that will cause unnecessary strain to your steering components.

When you lift your truck the tires move elliptically and your stance viewed from the front looks like this \----/ because the Caster and Camber is a "balancing act". To properly fix this you need to add negative CAMBER. The SPC will do that.
The SPC Caster should be set to stock "G", or plus .25* "F" setting and that should be good! Your alignment should be at 2*-2.5* of Caster.

Any higher above 3* will start to add un-needed strain on your steering system. I've seen serval steering rack fail due to excessive CASTER.

 

I currently have 1.75 inches of lift up front. My wheels are - 10 offset with a 265/70 /17 tire. I mounted a 285/70 /17 on the drivers side last week and had a paper thin clearance from the cab mount at full lock when lowered to the floor. The video states that these uppers can push the wheel forward .5-.75 of an inch. So two questions. Is this a good strategy for me to clear a 285 without having to do a cmc? Has anyone done this successfully without a cmc and if so what was your wheel offset? Thanks!

 

I'm going back to the shop for the fourth time next week. The issue is not enough caster. We are at +3.6 and it's not close. This time for sure going for over +4. Sweet spot on camber I have found is -0.03 both sides. If your lifted with 35's anything under +3 caster will be horrible.

 

I a assuming you are running SPC's. Set them to neutral, Max out caster from the bottom. Turn the wheel back and forth. If it rubs on the front now you are going to have to trim or get a high take off bumper. If it does rub, see if it drives strait. If it does cool, if not adjust caster on each side until it tracks strait. Lock down the lower cams.

Now get a floor jack, put it under front jack point. Barely loosen the nuts on the UCAs and slowly raise/lower the jack to set camber.

 

I should have been more clear... no I am currently on my stock uppers. I wasn't really asking about how to adjust spc's, but more about if they can be a solution to attempt to clear the cab mount and not have to do a cmc. Has anyone been able to use spc's and eliminate the need for a cmc with a 285?

 

I see, well yes you should be able to get the caster high enough to move the tire far enough forward to not have to do the cab chop, BUT you will start rubbing on the front bumper. You will have to do a lot of trimming to the bumper or get a high take off style bumper. Hope that helps.