Questioning UCA install.

Hey guys.
2nd Gen Trd off road
2" lift front and rear. there about.
JBA HD UCA.

so i was lifted 3" before on stock UCA arms and i got my alignment within spec. Found a deal on some JBA HD high caster arms and got them installed. ever since them, the caster is at 3 or 4 degrees. all other adjustments are in spec.

But now that moved my 265/70/R17 wheel back and its slightly rubbing on my mud flap. If i had 285/70/17 i would maybe be ok with stock uca but the JBA UCA i would rub my cab mount for sure.

i thought the UCA was supposed to move the wheel forward, away from the cab mount.

 

Howza bout a visual? (Pics)

 

Rubbing the mudflap.

 

Help me understand what's going on here on your UCA? Looks like they've been ground on and paint removed?

 

I can assure you that alignment does not have 3-4* of caster in the second pic.

 

the way I understand it, increasing the caster moves the wheel rearward to create more tracking stability that's lost with a suspension lift.

 

Positive caster moves the top back and the bottom forward in simple terms since the axis pivots thru the center. Positive caster improves tracking and stability.

 

Hers a simple pic of caster angles.

 

sorry, I wasn't clear. High caster UCA's move the wheel rearward, all other things being equal.

 

In essence yes. Since the caster line is no longer perpendicular that’s correct.

 

i bought these used. that is just paint chipping.

that picture is what my current suspension is at. same as the alignment sheet.

ok. sure. my question is.....a lot of people say you need to run a high caster UCA to fit bigger wheels. but this is the opposite. if i put on 33" tires, that will cause it to rub even more then stock caster with a stock UCA. I was getting good caster numbers with a 3" lift on a stock UCA. The only positive that i experienced is that the ball join allows for more downtravel.

 

I understand you bought them used but it looks like somebody took a grinder to them. That's why I asked.