Alignment, Caster, Clearance, and Driving Report with Light Racing UCAs

I'm running E, lowers maxed out, no trimming and still have my mud flaps on, slight rubbing

 

Not to try and confuse anyone but here are my settings. I'm currently on 285/75 R17 (33.9") and almost have all my rubbing gone at full stuff. I also have a a Cab mount relocation, bashed over the cab seam and trim trim trim. I walked into Firestone and asked who has dealt with adjustable UCAs, luckily there was a tech there that understood what I wanted. I told him to max out the caster and that he did! Unless he just fudged the numbers to get me out of there. The truck handles fine on the freeway, steering was a little heavier around town. No complaints. IDK maybe I'm just driving a death machine with this much caster.

 

Wow, that's a ton of caster. Looks like the arms are in position A which would give you a lot of extra caster.

 

i ran my SPC's up to 6.1 & 5.9 once just to try it since it worked with fitment. but it didn't drive so great. the caster was there but steering feel and weight shifting was inconsistent across the front. i am a caster whore, but that was too much for my truck at the time, so we reduced it to its comfort zone, which was 5.2 at the time. since then I've installed Marlin frame braces that have further reduced its natural position to 4.1 on both sides. how is your steering on the highway, when you're actually steering?

 

Initially, when I had the Mickey MTZ P3s on, there were no issues. It seems to wander a little at speed now after putting on the ridge grapplers. I'm assuming it's because my new tires are E load? I may back the caster off a smidge on my next alignment after I install my new coilovers, not sure yet.

 

my experience on this truck, about 3 years of trial/error and experimentation, is that for driveability this chassis is good into the 4-5deg range, but not higher without side effects. of course every truck is totally different. as I've modified the front here & there it's homed to 4.1 both sides. i run everything even: 0 camber and 0.05 toe-in, and 4.1 caster both sides. about to add adjustable sway bar links and gusset the steering knuckle and that may change things a tenth in caster, not sure yet.

i prefer the drive at 5 degrees but the truck doesn't like it anymore, so I'm a little more active on the steering wheel at speed with 4.1.

 

Just installed today along with bp51 coilovers. Should be about 2.5” lift on a 2019 Tacoma. I maxed out the LCA eccentrics for max caster and set spc to position D. What’s your guys guesses for my caster? I’m shooting for about 3, think I’m over?

 

My guess is 4+

 

We’ll find out. I’m hoping for about 3, think I should try position E instead of D? Gonna mount up tires today and take it for a test drive once I finish up on the rear end lift. I’m running -25mm offset so I need all the clearance I can get off the cab mount.

 

With the -25 offset, you might need to go to E to get the wheel farther forward, it depends on the width/height of your tire. I would see if they rub at D before getting an alignment done, and if they do rub go to E.

 

right on, thanks for the info. I’m running 16x8 scs f5’s -25mm offset, tire is 285/75/16 cooper st maxx. I’ll see how it looks today when I mount em up.

 

My truck had 16x8 with 0 offset wheels and 285/75/16 tires and with 1-1/4" spacers, they rubbed slightly with the SPC at position C. I removed the spacer and moved to position D and it was fine, so you might be real close.

 

no rubbing so far on the cab mount at full lock, but it’s real close. I got about 2.5” of lift in front. I’m maxed out at caster on LCA and at position D on uppers. Been fine tuning my alignment myself for a couple hours and got it pretty close. I Deff have some trimming on the front fender area and need to test the cab mount area at flex.

 

Update. Stress tested and been fine tuning alignment using good ol fashioned level and fishing line. Got er driving real nice and after flexing and testing just the most minuscule amount of rub at full flex it’s not work worrying about. I’m running 285/75/16 st maxx on 16x8 -25mm offset scs f5’s. No cmc but did have to do some trimming.

 

Anyone have pictures of their cam bolts with the LCA at max +caster?

 

So the furthest ticks on the cam bolt will be matched up with the middle marker on the cam guides?

 

you want the fronts “in” all the way and rears “out” all the way for max caster adjustment on lca.

 

Lol all good

 

So front is short and rear is long..That makes sense if the goal is to max +caster or push them forward. I'm clear on that part.
Looking at the eccentrics from pictures tho, It seems like the center is the longest edge. Is that what is lining up on the center of the tabs?

 

That's exactly what I needed. Thank-you so much!