UCA's and Alignment

I was wondering if anybody could help me understand the issue I am having with the rear toe and -.15 thrust angle. Also any other information is helpful. Here is my spec sheet. I have a 3 in lift and aftermarket ucas.

 

The rear is not adjustable.

 

It can be adjusted.

 

Keep in mind, the caster angles change when lifting the front end of the trucks *higher than the back*. With the factory rake you want your caster angles to be within factory limits, but when lifting the front you change the angle of the entire truck in relation to the road. So a lower-than-ideal caster number may be ok in this scenario. I think that is why me and others have had good alignment with stock UCAs.

 

It's not so much the changing the "entire angle of the truck", as it is changing how the wheel cambers as it is turned; thus affecting measured caster against what the alignment software is computing for stock geometry.

 

proper caster numbers are easier to obtain on a truck that has been leveled as the suspenion / frame as a whole has been tilted back (what positive caster is). This does not make it so that lower caster numbers work better it simply allows one to get okish within spec caster numbers easier.

Lifting your truck does not effect how caster is computed. A standard 40 degree caster sweep is going to yeild the same caster on a truck set to X deg on a 3in lift vs stock height.

 

Edit: Found what I am looking for in the first gen section...thanks for the info in this thread though. It helped my search! Keep on keepin on

 

What a great THREAD!! After reading through, I have learned more than I ever thought possible. That being said.....HELP!

I recently acquired my dream truck. A 2012 Toyota Tacoma TRD OFF-ROAD. The problem? I bought it used and the knuckle heads who had it before me did some "less than stellar" modifications.

The 16'' wheels are wrapped with some (absolutely stellar, and darn near new) 265/75/R16 GOODYEAR WRANGLER Duratracs. The problem? She's got a case of the "pigeon toes" due to a lift/leveling kit which was applied by the previous owner. ALL I want (well, maybe not ALL I want) is to save my GOODYEAR meats from wearing inappropriately due to a case of pigeon toe.

NOW, I am aware that lifting the truck (especially with a cheap leveling kit) will change the alignment of the front end. I understand there are "limits" as to just how "perfect" you can get the alignment with stock UCA's (as I have.)

But I was told today by "the best alignment man in town" that he "will not touch" my truck, because he feels he would not be able to produce satisfactory results.

All I want......is for my steering wheel to be straight, and a little bit of confidence knowing my front tires won't wear like and Arkansas citizen's sneakers. (No offense, go pigs.)

It should be noted, at this time my truck does not pinch, pull, itch, swing, vibrate or veer. It's just a tilted steering wheel.....and a case of expected pigeon toe. SO IF YOU WERE ME, what would you do? Can this be fixed?

Pics or it didn't happen

HER

The Problem

The reason (told from the rear, at least.)





Hands off the wheel, driving straight on flat surface.


*front shock/struts are original....and equipped with a similar billet spacer (on the top of the coilover, of course)

 

My 15 OR has a loose steering feel at high speed after alignment with a 2.5" lift. Wondering if it's the added toe the alignment shop did might be why.

Current alignment
Camber .05 .03
Caster 2.8 3.0
Toe .13

I used to be at 2.4 caster and 0 toe and camber but the truck was pulling right a bit and felt wandery. The shop added the extra toe saying that there would be no adverse effects to tire wear and it would help keep it tracking like stock and it was common to add a bit of toe. It did fix the pulling and the truck drives great now below 60 mph. The loose feel over 60mph started after the last alignment. Is a toe of .13 acceptable? Could this cause the loose feel? Or is it something else. Im on 275/70/17s. Wonder if tires are contributing.

 

A better camber setting would be +.02 -.03 left, and 0.0 right. The offset is for road crown. They may have left it with more to keep the caster high. You shouldn't need that much toe. It will likely cause some tire wear, but shouldn't cause wandering. I would start by getting the camber down, and recheck the caster. Even caster of 3 should be good. What suspension mods do you have?

 

Just a icon stage 1 with icon rear aal and LR UCAs. I was really excited about the feel of the alignment until I went on the highway yesterday. Feels like 2 inches of play in the steering over 60 mph.

 

That feeling is usually lack of caster, but could be from the camber settings. Is the higher camber right or left? You should never have higher camber on the right. Did you get a print out?/

 

Higher camber is on the left.

My old specs that was pulling right had a 0.08 toe 0.6 - 0.5 camber and a 2.7 caster. Not that far off from my current except the toe now is .13. The old alignment was pulling right and felt really wandery. The new one feels solid, like stock except at high speed

 

If that's 1.3 degrees of toe in per side, that's an insane amount of toe in. About 1.4 INCHES of total toe in.

 

OMG I'm an idiot. It's .13

 

OK, much better. that works out to a hair over 1/8" of toe in.

 

Revival! This thread should never die- too much useful info here.
Thought I would post my numbers since so many struggle with stock uca vs aftermarket.

Toytec adjustable coilovers for 2 5/8" lift, toytec aal for 1 7/8" lift. (yeah..I was super OCD on my measuring, flat ground, took mult measurements, half tank only, etc) Stock uca, sway bar relocate.
Caster is 2.3 and 2.5 (done via lca), camber 0.2 and 0.3, toe 0.1 and 0.1 and the truck drives great, felt like stock to me.
OF NOTE: I have an awesome alignment guy here in Tucson and he knows 4x4s and lifts. He balanced everything just right so I would get good caster and camber and used every adjustment available. He also did my alignment on my 1st gen with a nearly identical lift and stock uca and I had that truck for 12 years on 2-3 sets of tires. Nearly 70,000 miles on one set. So the wear was great.

I think people are not always measuring accurately and probably have more lift then they think. My totyec said it came preset at 2.5, but it was closer to 3. I had to dial it down. I think you definitely can get a good alignment with stock uca on 2.5 lift.

 

Ditch the terrible spacer lift up front and the block from the rear. You'll clear those 265/75 Duratracs just fine at stock height and will be able to get the alignment to spec.

 

I’m going to an alignment shop Tomorrow sooo explain to me like I’m a 3 year old? What should I ask them to do? I have 285/70/R17 w/ Camburg UCA and king shock:

PS does it make a difference if I have a sso slim bumper with a winch?:

 

Anyone??