Should i get new UCAs

micahgeorge

Test Drive
Location
jacksonville
Im about to do the PML and have rear adjustable shackles but would like to get as much lift in the front as possible. Should I get new UCAs so I have more bump stop clearance? If so what are some good after market ones?
 

robcarync

Sliders
Location
Raleigh, NC
I reccommend it! I pioneered that combination several years ago! I did a PML with the shackles a little lower at first, then saved up for UCAs a few months later. When I installed the UCAs, I bumped up the shackle to match.

The adjustable shackles in the rear, maxed out on the highest setting goes great paired with the UCAs in the front!

Looks even cooler with a 2" body lift :)


Just for the sake of being thorough for anyone else whom may be interested:


2 1/8" Suspension Lift


7860524158_312ed86464_z.jpg



Note: I have a larger than average bump stop gap at the front UCA. The height can be increased another 0.25" at the front.


Quick Description
Moderate suspension lift for people that want more than a PML, but don't want to stiffen the rear suspension by adding leaves. By using a 2 1/8" lift shackle and 3" lift UCAs, you also have more control of your vehicle rake by being able to lift the front 7/8" higher than the rear, allowing you to obtain a more leveled ride height and more moderate bump stop gaps.


Materials
AC Adjustable Shackles (2 1/8" maximum lift)
3" AC Adjustable Upper Control Arms
Upper Control Arm Cam Bolts


Concerns or Notes
You must get an alignment afterwards using the specs for any Suspension Lift


1. Set the Camber to 0°, or as close to it as
possible.


2. Try for getting the Caster to be between 0.3° and
0.6°, set differently between the right and left
side, with the left side being less than the right.


It doesn't matter what the Caster is, just as long as
you get the most Caster you can on the right
side, then set it so the left side is less by 0.3°
to 0.6°


Camber = 0.0°L.....0.0°R
Caster = 0.9°L.....1.2°R
Toe in = 0.08"L...0.08"R
Total toe = ...0.16"


You must maintain a 0.5" bump stop gap between the stock bump stop and the aftermarket UCA


Nice To Have
Idler Arm Brace
3" Lift shocks
Remove rear sway bar


DIY
Shackles and adjusting the torsion bar height (PML):

http://xterranation.org/showthread.php?2812-How-To-PML-Fully-Explained!&p=77851&viewfull=1#post77851


UCAs:
http://www.clubxterra.org/forums/showthread.php?t=11604
http://www.clubxterra.org/forums/showthread.php?t=38113


You may need to Re-Index torsion bars:

http://xterranation.org/showthread.php?2813-How-To-Re-Index-Your-Torsion-Bars


Links to Purchase
AC UCAs:


6cyl 4wd: https://www.4x4parts.com/nissan/xterra-front-suspension-lift-p-79.html
6cyl 2wd: https://www.4x4parts.com/nissan/xterra-front-suspension-lift-p-85.html
4cyl 2wd: https://www.4x4parts.com/nissan/xterra-front-suspension-lift-p-86.html


AC Adjustable Shackles:


https://www.4x4parts.com/nissan/xterra-adjustable-lift-shackles-p-5612.html


Cam Bolts:


https://www.4x4parts.com/nissan/cam-bolts-p-6123.html


Idler Arm Brace:


AC: https://www.4x4parts.com/nissan/idler-arm-brace-p-59.html


TC: http://www.polyperformance.com/shop...Frontier-Xterra-Idler-Arm-Gusset-p-17297.html
 
Last edited:

TJTJ

Skid Plates
Founding Member
Location
NJ
The aftermarket UCA have one primary purpose, to allow alignment at 3" lift height.

If using them for a lower than 3" lift height, but higher than ~ 1.5", they work fine, and do add about 2" of down travel, which is nice.

If you add the new UCA, and crank them up to ~ 1/2" upper stop clearance, you essentially have a FRONT ~ 3" or more lift.

You want the nose to be about 1.5" lower than your butt for the truck to work best, and that's pretty much the OEM rake....so when people do a 3" SL, they raise both ends 3", so the front is still lower by the same amount relative to the rear.

Newbs who want the truck "Level", in addition to bringing joy to those who sell newbs "Leveling Kits", simply lift the front ~ 1.5" more than the rear, eliminating the rake.

So, if you use new UCA, after maxing up your butt, just raise the front until you have it ~ 1.5" lower than the rear, and you're good to go.


Remember, the "Perfect Suspension" allows the tires to go up/down with the undulations in terrain, while the truck stays dead level and stable. Too little up travel left means that corner of the truck is tipped up instead of just the tire. Too little down travel left means the truck tips over, down into the hole, instead of just the tire going down but the truck remaining stable, etc.


With the new UCA, you get ~ 2" added wheel travel. If you use it all to make the front higher (Uses "pre-drooping" to raise ride height), that leaves too little DOWN TRAVEL left to follow uneven terrain....so that front corner of the truck will be tipped down at depressions/holes, instead of just the TIRE drooping down while the truck stays level. If you use the total wheel travel more proportionally, you get enough up/down travel to allow the truck to glide along in a more stable fashion.

:D

AC's UCA are what I'd get if I needed new UCA at this point.
 

robcarync

Sliders
Location
Raleigh, NC
Note that the adjustable shackles lift 2 1/8"...so you will reduce your rake by about an inch if you max the front lift. You will still have a nose down rake slightly, which of course is desirable, as TJTJ mentions.

My stock rake was exactly 2", and it is now right around 3/4 of an inch. I don't think the rake had much of an impact on handling and mileage, etc, but of course is hard to tell now since I have no sway bars, 2" body lift, heavy steel armor, etc. I never noticed a difference before all the extras either, though.

Also, I only got 1" of front lift from my PML, so I wanted to get the UCAs to make sure I had good alignment and wouldn't chew up tires and to make up for my lackluster PML in the front end.
 
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