Caster and rubbing issues

So I have removed the mud flaps, chopped the cab mounts, folded the pinch weld, cut the fender metal, trimmed the fender plastic, and trimmed the fender liner. I still rub on compression with the wheel turned at various points, especially under full lock on the cab mount chop plate. Right now my lift and allignment stats are as follows.

American Racing Artillery 17x9 4.53" backspace -12mm offset
Nitto Trail Grappler 285/70R17 33.15" x 11.81"

OME 885x with trim packer below left coil
OME shocks
Desert Products Uniball UCA

TSB leaf with ICON 3 leaf add a leaf and overload removed
OME shocks

Caster 2.4 Left 2.6 Right
Camber 0.0 Left and Right
Tow .02 Left and Right

It seems to me the 2 degrees of posititve Caster from the Uniball UCA actually caused rubbing and that for the limited lift I have I did not really need it. Oh well... I'm not removing it.

To me this leaves only ONE thing I can do to move the wheel forward and stop rubbing. I have to add Caster to move the wheel forward in the wheel well.

My questions are these... how much does each degree of Caster move the wheel forward? How much Caster is too much? What happens as the wheel compresses if I add too much Caster?

I am estimating I need the front wheels about .25" more forward to get full clearance.

 

How much lift does that give and where exactly are you rubbing? Pinch weld area still or flares? I still rub slightly at the top above the pinch weld and flares (got longer bump stops to limit up travel) and have about 2.5-2.8 caster! I believe they need to add more caster from the bottom to bring it forward as the top (uca's) moves it back in the wheel well! Maybe try 3 on the caster? Worse thing is you have a little more bump steer or rub on the front bumper?

 

A mid travel lift has nothing to do with tire rub
(bump stops limit travel not lift)

Your issue is your caster, tire width, and wheels.

If you wheel hard with 285's your going to rub -- I rubbed with my 265/70/17's on stock wheels.

 

I was rubbing the pinch weld but hammered it even flatter. I can no longer stick my finger behind the pinch weld. I only did that this morning so I dot know if it clears now. It was rubbing about 1 inch up to about 4 inches up. I have cut back the flares so they dont rub. Same with the metal lower fender... I cut it and rolled the edge. I rub the cab mount mostly now. I used the cab mount chop plates from BAMF.

As far as my lift... heck if I know how much it gave... probably 2.25" if I had to guess and pull a number out my ass without measuring.

I just want to know how much caster is TOO much. Going to get a new alignment in the morning then on a road trip to Colorado once I pull out of the bay (will be pulling in loaded for the trip) and want to be able to wheel without ripping off my tread lol. I also do NOT want shitty road handling. I ususally drive fast on road trips over 1000 miles because it takes like a day and a half to get where I am going and I dont have an extra half day to burn up going 60 mph.

 

3.5*-4*

set it at 3.2* and see what happens IMO. it's not like you can do anything else besides buy new tires or new wheels at this point or chop more cab mount

 

I've never seen a formula for that.

I think I've heard that the 5 lug has like 5 or 6 degrees of caster from the factory.

Same problems as you're having now - wheel position within the wheel well.

 

What do you do when your suspension comes up and back and you are THIS close. Im worried that more caster might not move it forward enough... that it might take like 5 degrees or something ridiculous. Anyone made caster adjustments to gain clearance?

And to those guys who think you are gonna clear 33.5" or larger tires or 12" or wider tires without MAJOR MAJOR reconstruction or a drop bracket lift... you are crazy!

Here it is under compression



And how high the lift is

 

Everything I know about caster, rubbing, and adjustable UCAs is in this thread:

http://www.tacomaworld.com/forum/suspension/158795-alignment-caster-clearance-driving-report-light-racing-ucas.html

 

I also had over 3 degrees before correcting... and am rubbing after getting to factory max. I dont have any ability to adjust with my UCA set up other than perhaps making custom washers to reposition my UCA like 1/16" forward, which seems trivial. How much space did you gain with just a couple degrees of changing caster? It sounds significant.

 

A few degrees can make all the difference.

I'd just push it as far forward as you can, I don't think you'll get to the point you have too much caster. I know some people seem to think that too much caster can attribute to bump steer but I've never seen any definitive proof.

This is in regards to the LR UCAs but...

 

I made multiple changes. But I was rubbing before the cab mount chop, not after it. So I changed alignment, trimmed more plastic, and did a pretty agressive CMC.

But I didn't measure before/after. Sorry.

 

My alignment guy pushed the caster forward till I lost camber. Camver went from 0.0 to 0.3 left and 0.1 right. Caster is 3.5 left 3.6 right. It moved my wheel forard exactly 1 finger width... so 1 degree = roughly 1 finger width for future reference lol. My wheel is centered in the wheel well and I cannot make it rub anywhete now..
Clearance is 3 red cunr hairs... but I dont rub and I am approaching Amarillo on my way toDenver and handling is great.

 

Good deal

 

I could fit 34" pizza cutters no problem with no can mount chop. Right now I'm running a tall 33" with zero clearance issues. All I did was remove my mud flaps.

X2

 

Cool man.....glad you got it squared away!

 

Removed wheel spacer and it worked amazingly!!! No more rubbing. Thanks guys

 

Im at 5+ degrees of caster to get good clearance on pavement. Full speed turns and bumps no rubbing issues. Drives great.