Most UCA's Have a huge design FLAW!

UCA are built to correct alignment issue due to lifting your truck to fit 33" tires.
The Design "Flaw" is the addition of CASTER!
Most UCA companies build their UCA with additional CASTER.
This is WRONG!!!!!
When you lift your truck you loose your CAMBER.
When a Manufacture adds CASTER, they are Creating a new issue that will need to be fixed. The tire will be moved rewards to increase CASTER and amplify the rubbing issues on the pinch welds and the Cab Mounts.
This is why everyone does the CMC to fit 33" tires. Which if done correctly is NOT necessary!!
((It is necessary for 35" Tire on a 3" lift!))

This is why Stock UCA can clear 33" tires easier than aftermarket UCAs.
However for years the industry has been chasing this "FALSE Ghost" of Caster!
The stock UCA can get the CASTER in to spec. But your Camber will be bad!
When you lift your Tacoma you need to correct the CAMBER! Not the CASTER. (Both go hand in hand) But correcting the Caster Causes additional Problems.
Correcting the CAMBER is the correct way to do it!


(I am in no way affiliated with SPC)
SPC UCAs can do this for you at the most economical way possible.
Icon UCA's can also do it but you need an alignment guy that is a Jedi Master to set them up correctly!

SPC took out the guess work! (I really don't think they knew it at the time) When they built these UCA's. But it actually solved the issues when lifting your truck 2"-3".


My recommendation when lifting your truck is to get a set of SPC and set them to "F" or "G" setting and move your LCA alignment Cams so your tire is optimal as forward as it can be set. Use the UCA sliding feature to correct the Camber! You will need to make clearance up front and move the fender liner forward and trim thee lower bumper plastic. But that is very Simple compared to relocating you cab mount or a cab mount chop, and cutting and hammering back you pinch welds.

So Please take what I say here with a grain of salt.

Please think about what you just read before posting a shit storm of how you think I'm wrong.
If you have data and facts (Not Opinion or Hear-say) I'd love to have a civil discussion on this subject! Who knows?? I may be wrong. I'm open minded to that possibility!

But From my R&D this is currently what I have found!
If you'd like to read about lifts and alignment I made stickies in my Sig. which are over 10 years old but still has information that can be useful.

I don't get paid for this. I do it because I'm O.C.D. and when I identify a problem I need to resolve it.
And when I find a Solution I like to help people out.


Hope this helps! Good Luck!

Have a Great Day!!

 

And this is why I run SPC arms!

 

Caster is also reduced when you lift. This is due to the anti dive geometry of the upper arm pushing the top of the spindle forward as the arms are rotated down.

 

Yes! You are correct!
But by making UCA's with higher Caster they cause additional issues that now need to be resolved. e.g. CMC or Cab Mount relocation Pinch weld cutting and bending.
Moving up to 33" tires doesn't need to be so difficult. And actually can be really easy.

((This is not addressing wheel offset and width.)) Which causes it's own set of issues.

 

https://www.youtube.com/watch?v=d4A3QGLEpTQ

 

Exactly! Always think its funny when people try to shoot for 4-5 degrees of castor, when in turn its making everything worse. I have my stuff "pushed" as far forward as I can with the Spcs, and run around 2 degrees of castor. Then just dial in the camber to what I want (been running -1.5 degrees with good luck). Clear 35s with the standard cmc and basically don't hit the firewall with them either.

 

@toku58 Do you think Scotty's can do alignment right? Or is there another Jedi Master?

 

Are you asking about the Icon UCA's??

 

Thank you for being very loud, and not wrong. Your empirical data is much appreciated

 

SPC’s over here

 

UCA companies design for additional caster with the lift with driveability in mind. I think that your main concern is fitting the tires without having to do a cab mount chop or pinch weld trim. Yes it can fit and not rub, and run on road with normal driving. Just your driving characteristics won’t be the same with less caster. But its not a myth. And I wouldn’t run SPC arms again. I don’t trust that company. I had their UCAs and they cracked off at the weld. Street and mild trail driving only. When I contacted them, they knew of the issue, but did nothing to notify those who already bought them. They sent me their new updated one and it went straight to Craigslist. I’m better off with Camburg UCAs and peace of mind.

 

Apparently their first gens had some bad welds and were revised. I have their newer versions and they've gone through some hard hits and are completely fine. But that being said I do slow technical trail rather than sending it through the whoops. I highly recommend them to anyone who isn't building a prerunner style truck.

 

What caster are you running?

 

I have my LCAs pushed all the way forward, I think I'm at 4'? Can't find my alignment sheet. I'm going to push the tires forward even more by reducing castor down to 3' or maybe 2' of castor. Probably set it at F. @Buttskevin21 what did you set yours at?

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No. About a shop called Scotty's Alignment & Brake Services in Pearl City. They have been the go to for modified trucks.

 

I know where Scotty's is. I've been to him for my alignment. (Unfortunately his Customer Service isn't very good.) He doesn't take appointments. So you just need to go down and it's a hit or miss on when your truck can get aligned. Could be on the spot or it could be hours???

If you use the SPC UCA's? I gave you the optimum settings. So you wouldn't need a "Jedi Masster"
But if you go with adjustable heim joint UCA's like Icon or Camberg than you would need a "Jedi Master"
I take my truck to Kapolei Good Year their tech Mark is a cool guy and has a decent understanding of Toyota alignment.

 

This is not the correct image for the SPC 3rd gen Tacoma UCAs.

 

Updated.

 

My main concern is Drivability and fitting the tires "correctly". On setting "F" My Caster is set at 2.5*, Camber is set at 0*, and my truck drive perfect!

No rub No CMC. with only 2" lift. On 285/70R17 General Grabbers on 17x8.5" Icon wheels, and Nitto Ridge Grapplers on 17x9" Procomp wheels. (Yes my truck is only 3 mo. old and I went through 2 sets of tires because I didn't like the look)

Never rubs off-roading full stuff!

Back in 06-07? I did test on Camburg UCA's and found design flaws that I notified them about and they did a redesign.
In 09'ish when SPC first released their Tacoma UCA's (It was called "Light Racing" back then) I did tests and found that they had a manufacturing flaw in their ball joints (assembly issue they were not aware of), notified them and they fixed the issue.
A lot of companies when first attempting to build products have issue that need to be resolved. Toyota is exactly the same. (Need the Bugs worked out)

 

You will rub your pinch mount regardless of the clearance at the back of your tire when completely stuffed on hard hits.