Just installed new Camburg UCA's

[lewisp]

The camburg ucas are now installed on my runner. I have a 2.5" lift up front and never really had any tire rub unless flexed before installing the camburgs. Now, after having them installed, my tires rub on the inner fender when backing out of a flat parking spot! Why is this?

Thanks

 

[txbonds]

Not sure on the why but mine started doing that when I put on light racing UCAs. But mine happens when backing and turning.

 

[Xinirgi]

Did you get your truck re-aligned?

 

[AZ_Trails]

Could be the additional caster that you got with the new arms. If I'm not mistaken, adding caster with the UCA pushes the tire further to the rear in the wheel well.

 

[Mike&Ike]

Could be the additional caster that you got with the new arms. If I'm not mistaken, adding caster with the UCA pushes the tire further to the rear in the wheel well.

This is true, if you have not done so you need a new alignment.

 

[FROGrunner]

Could be the additional caster that you got with the new arms. If I'm not mistaken, adding caster with the UCA pushes the tire further to the rear in the wheel well.

Yes increasing caster will help with steering "wandering" but will also move the wheel more rearward upon compression.

 

[BrianSD_42]

I thought these aftermarket UCAs were supposed to increase the space between the tire and the UCA?

With my factory UCA I have about 3/4" from the 285 tire.

 

[AZ_Trails]

I thought these aftermarket UCAs were supposed to increase the space between the tire and the UCA?



With my factory UCA I have about 3/4" from the 285 tire.

The aftermarket UCAs will generally put more space between the UCA and the sidewall of the tire. What the OP is talking about is rubbing between the tread of the tire and the rear of the wheel well, usually caused by additional positive caster.

 

[BrianSD_42]

OK thanks!

 

[smkd13]

Could be the additional caster that you got with the new arms. If I'm not mistaken, adding caster with the UCA pushes the tire further to the rear in the wheel well.

You a little backwards. Wen you add caster it will move the tire forward as it is positive caster. Here is a drawing to explain:

Think of a front wheel on a shopping car. The wheels trail behind the top picot point and this they are trailing and give stability as there is no wandering. If if you turn the wheels around then they become erratic and go where they want because they have nothing guiding them. Make sense???

I don't know how much castor is built into the Camburg arms but I thought they where suppose to add some castor to being back into stock spec.

Get an alignment and smash those pinch welds lol btw make sure you go to a good shop as a lot of The time they have the green horns doing alignments. Ask for the experienced guys to do it

 

[AZ_Trails]

You a little backwards. Wen you add caster it will move the tire forward as it is positive caster. Here is a drawing to explain:

Think of a front wheel on a shopping car. The wheels trail behind the top picot point and this they are trailing and give stability as there is no wandering. If if you turn the wheels around then they become erratic and go where they want because they have nothing guiding them. Make sense???

I appreciate your drawing, but you have it backwards. The front wheels of a shopping cart have negative caster, not positive. The front wheel of a motor cycle has positive caster - the steering axis of a motor cycle points toward the rear. If it was as you describe, you would never be able to take your hands off the bars and would always have to "hold" the wheel straight.

Do a google search for "caster angle" and you'll soon realize that you are the one that had it wrong.

My original post stands as is. Adding aftermarket UCAs moves the upper ball joint to the rear of the vehicle. From what I remember, most of the unadjustable UCAs provide an additional 2* of caster.

 

[EatonKyleH]

Tis a case of everyone is a tad bit right and a tad bit wrong. It depends on if caster is being adjusted from the top or bottom of the spindle.

Quote from SPC and the light racing install guide.

"If Caster is set for max position by the OEM lower cams, and final alignment achieved with via the SPC upper balljoint setting, more tire clearance may be obtained at the rear of the wheel opening"


And a wonderful explanation found here at this link on Tacoma world that explains adding caster at the lower OEM eccentrics vs. an aftermarket upper joint.

Alignment, Caster, Clearance, and Driving Report with Light Racing UCAs - Tacoma World Forums

Sum up from it:

* If you increase caster AT THE TOP of the spindle, you decrease clearance, because that moves the spindle hub back.
* If you increase caster AT THE BOTTOM of the spindle, you increase clearance, because that moves the spindle hub forward.
* On the stock truck, caster and camber must be played off against each other, because the combination of eccentric cams on the lower-control-arm affects both caster and camber.


So, to maximize clearance:

1. First, Maximize caster using the eccentrics on the lower control arm. Do not worry about camber at this time.
2. Reset the caster cams on the UCAs to the minimum value to bring Caster to an acceptable value. I decided to trade off a little less caster for a little more clearance here, and moved the UCA cams to the "+1" position (One degree LESS than neutral, and two degrees less than I started)
3. Set the camber using the UCA adjustment slide.