Alignment specs after SPC UCA install (1 Viewer)

[ga12r1]

I took my 2000 LX to a Firestone alignment shop yesterday after I installed SPC UCAs last week. . After talking with the tech and showing him the SPC adjustment instructions I decided to let them go ahead with the alignment.
15 minutes later the tech came out and said they were done. He showed me the printout of measurements and said that the alignment is "right for your truck with the tires and wheels you have".
It looks to me that caster is still out of spec (1.4 left and 1.8 right) and they didn't touch a thing on the UCAs. They only adjusted toe.
I had the ball joint set in position D and I explained that more caster could be brought in by moving the ball joint to position C shown in the instructions. The tech said that would be a bad idea and again said "its right for your truck"
I am running a sensor lift and 295/16 KO2s on SCS wheels.
Question is should I move the ball joint to position C and take it back for another try or should I try to get a refund and find another shop? The shop knew I had adjustable UCAs when I made the appointment. I feel like if they didn't understand how to adjust them they shouldn't have done the alignment and charged me for it? What does mud think?

 

[ga12r1]

Position C adds an additional 1* of caster BTW.

 

[KINGER]

How does it handle at highway speeds? Does it feel like something needs to be adjusted?

I'll be installing these soon so I'm curious why you think the shop failed to align properly.

 

[abuck99]

The fsm "range" is 1.8 to 3.4 so you are not in spec on one side and just at the bottom end of spec on the other.

The more you lift & adding oversize tires you'll want to shoot for more caster towards the upper end of factory spec to find a good return to center and straight tracking. If you can get there with out a rub.

The SPC UCA is probably a new thing for the alignment tech, which requires a little more than average thinking,attention and input to get things adj. where you want them. To be fair, expecting the alignment tech to adjust the ball joint position is probably expecting too much. You'll need to do that, and have it ready for them to simply adjust the cams for caster on the UCAs, and loosen the ball joint for toe. Keep it simple for them to get the best result. I took mine to a very good alignment shop who said they were familiar with the SPC UCA(not), and they needed a little help to figure it out. Which is why it's good to stand by and make sure you get it where you want it.

On setting D you should be able to get close to 2.4 +\- degrees of caster, with UCA adjustment cams in the full postitive position. Look in and check to see where they are set.

I'm running setting C and have 2.8. & 3.2 respectively, with the UCA cam in the center of its adjustment range.

Go back and have them adj where you want it.

 

[LandCruiserPhil]

▲this▲ the main reason IMO to use SPC over any other arm available is the ability to have the most control of your caster. Getting your caster at the top of the range will make driving at speed much more enjoyable. You need to find a place that understands SPC control arm. I recently had the same set up discussion with our local dealership that has installed tons of SPC arms along with a couple of the tech also running them.

 

[ga12r1]

Thanks: that's exactly what I was thinking. The entire reason to install the SPCs is to get back towards the upper end of the caster spectrum. Not just barely there.
I think I will m0ve the BJ to position c and take it back to them.

 

[LandCruiserPhil]

Thanks: that's exactly what I was thinking. The entire reason to install the SPCs is to get back towards the upper end of the caster spectrum. Not just barely there.
I think I will m0ve the BJ to position c and take it back to them.

Not your job IMO thats what you are paying for but thats just me

 

[abuck99]

If they installed the UCA, it's on them to correct the ball joint setting. But since OP installed the UCAs and and took it for alignment I think he would take charge of it. It's not a typical adjustment with a standard alignment.

 

[ga12r1]

Well second try was better...
I moved the ball joint to position C. It only took about 15 minutes and I trust myself to do it more then the shop.
Caster is better. Would have liked to have everything in green but I don't think it's in the cards with these guys.
I was under the impression that the broad strokes are done with the ball joint position and then fine tuning was done with the cam bolts. My cam bolts are still in neutral position. They have only adjusted toe. The tech now tells me if any more caster is introduced toe cannnot be corrected. So that's that.

 

[abuck99]

Not sure about the toe being limited by the degree of caster- that's a new one for me.

The tech should be able
tweak the alignment to how you intend to use it. More or less toe and camber set up for street vs off-road use.

You're pretty close- but there's still room for improvement if you want more adjustment.

Here are my current numbers based on ball joint setting "C" and the adj cam in the center position.

Atlanta is a long way to come for an alignment but there are a few knowledgeable shops here that understand how to set these up.

Good luck.
Before SPC install

After SPC Install

 

[Kofoed]

That first caster measurement was out. My FSM says 2-4 degrees caster and zero camber. Mine was at 2 degrees caster. It is really twitchy on the highway, with the more weight I'm carrying, the worse. I will be switching the SPC nut to the "E" position and going back. I want my vehicles to cruise down the highway without vibration or shimmy.

 

[jLB]

That first caster measurement was out. My FSM says 2-4 degrees caster and zero camber. Mine was at 2 degrees caster. It is really twitchy on the highway, with the more weight I'm carrying, the worse. I will be switching the SPC nut to the "E" position and going back. I want my vehicles to cruise down the highway without vibration or shimmy.

Wouldn't "E" be the wrong direction? ("E"=stock caster, "D" adds 1* over stock, "C" adds 2* over stock)

 

[Kofoed]

I don't remember off-hand. I'll have to look under there. I'll do the reset myself, then take it in. Who knows, the guy may have moved it from my setting....

 

[jLB]

 

[abuck99]

FSM specs you want to shoot for.

 

[KINGER]

Thought I would post these specs and results for the benefit of those with stock AHC suspensions looking to install SPC UCAs.

Installed SPC UCAs (caster nut in position "D") and brought to my favorite Mavis for alignment. Below are the final specs. When I asked about the nearly 1 degree delta between the left and right caster values they said that this is normal and compensates for the crown of the road. Okay. It drives great going down the road, so I'll monitor and consider feedback from here...

I'm incredibly happy with these arms. I was hoping to solve a number of problems with them: worn upper BJs, squeaky cycling of the suspension up and down, loose steering and twitchy highway manners, loud noises over potholes, phantom shimmy and vibration above 65 mph, floaty scary feelings over expansion joints. Upon first test drive these arms appear to have solved them all. I'm sure OEM arms would have solved the squeaking and banging but the extra caster the SPCs dialed in has greatly improved the highway manners.

AHC note: even with the height position sensor placed in the bottom of the SPC arm brackets I had trouble lowering the front to get rake. Right now I only have about 0.5 inch rake (20.5" front, 21" rear, hub center to fender).

 

[Terra Dactyl]

I have a 2003 100 with a 2.5 inch lift. I recently put SPC greasable upper ball joints in. I putt it in position D as recommended. It now seems a little squirrelly on the highway at speed. Do y’all recommend that I move it to position C? Where does the ball joint need to be positioned in the UCA slot? I have not found a shop in the Phoenix area to do the alignment.

 

[AlpineAccess]

Hey Gents, quick question on this.

I've got my SPC arms at 3.5* caster on both sides right now based on most recent alignment. I need to go back today, am thinking about having them the first rail road crossing I bombed over my steering wheel shifted. I checked and they didn't crank down my front left eccentric so it spun.

Thinking about having them back it off to 2.5* - 3* and curious where others found a sweet spot.

I'm at 21.25 in front and 22.5 in the rear.

 

[AlpineAccess]

Bump

 

[ga12r1]

Hey Gents, quick question on this.

I've got my SPC arms at 3.5* caster on both sides right now based on most recent alignment. I need to go back today, am thinking about having them the first rail road crossing I bombed over my steering wheel shifted. I checked and they didn't crank down my front left eccentric so it spun.

Thinking about having them back it off to 2.5* - 3* and curious where others found a sweet spot.

I'm at 21.25 in front and 22.5 in the rear.

The more caster the better IMO. Unless it’s causing tire rub issues, why do you feel like you should run less?