I've been reading mixed responses on this.

Trying to determine are aftermarket UCAs needed to run 285s on a 3" lift without rubbing. Not just on road but offroad as well?

This will be with stock 2015 trail edition rims.

Thanks in advance! Try to resist flaming! I've searched. Google searched. I'm getting results. Just mixed.

Longer UCA's are needed for 3" "extended travel" lifts not so much the tires. A 2" lift typically does not require UCA's and should still fit 285's with proper alignment. I have a 3" lift with UCA's and haven't eliminated my rubbing issues, but that's because I have 9" wide wheels. When it comes to rubbing, the main advantage of aftermarket UCA's is that all of the ones I'm aware of give at least a few degrees of positive caster. This moves the entire wheel forward in the wheel well and prevents rubbing on the body mount. Caster adjustments can only do so much, which is why you can't go bigger than 285's without doing a "body mount chop."

I have 285s KO2 on trail wheels with a 3in OME lift with no issues.
But remember, not all tires are made equal. MT tires might need a UCA/body mount chop

Short answer... it depends.

I ran stock UCAs with a 3" lift and 285s for a while with no major issues, but my truck was twitchy on the hwy due to not having enough caster in the alignment. I had no rubbing issues after pushing the fender liner forward... I was running stock SR5 wheels with BFG KOs and an OEM lift.

In the long run, you will most likely want aftermarket UCAs to compensate for the lift and get better caster angles. One odd thing about alignment on these trucks is that they are all very different. Some are easy and can drive OK with stock UCAs, others are a PITA. It is a bit of a roll of the dice if you are one of the lucky ones or not.

I have total chaos UCAs and like @4Rager said it moves the wheel forward allowing more clearance away from the rear portion of the wheel well. The only rubbing I have is BARELY on the thin plastic from the mud flaps. However, I still had to trim a 1"x4" (4" diagonally from the 1" cut) piece of fender from the front bumper and then heat gun mold the fender liner away so it looks cleaner and prevents rubbing on that too.


Basically, UCAs give you stock suspension geometry but still requires some fender work. Its very light so a dremel and heat gun are your best friends. Remember, not all tires are created equally so your results may vary from mine. But expect trimming regardless... minor trimming with aftermarket UCAs and probably slightly more in-depth trimming without.

I am lifted Icon stage 1.

On stock wheels, no. But you will probably end up with aftermarket wheels at some point, so spend the extra couple bucks on control arms now.

Thanks for all the feedback everyone. Seems like i dont "need" it but i "should" buy it.

Anyone running 285 mud terrains on trail rims with 3" lift?

@awpsome , Just buy em already.. You know you'll end up buying more stuff if you stay on this forum.

HAHA very true, but i am unfortunately not made of money.

Only wanting to buy what i absolutely "need"

So hard to sift through all the forum threads and posts because there is never a clear answer. some say one way and some say the other.

Money not having to spend on UCA can go into other important "needed" items haha

yeah, there's always a need :P. Black Friday Sales soon!

I'm installing Bilstein 5100's on my 15' Trail. I'm going to set them at 1.75" and add a 1" cornfed spacer to the rear. Looking for a level ride with a small bit of lift. I would like to put 285/70/17 General Grabber AT2's on it, but don't want to do a BMC. Anyone ever run these before with a small lift?? Not doing UCA's either.

I just don't want any rubbing.

I have 285s, trail edition, trail wheels, no spacers, and stock UCAs. I have a very slight lift with fox 2.5s on the front adjusted about as low as possible. Stock UCAs work fine for me. No rub other than slight on the front bumper cover in reverse on one side. Moving the tire forward with aftermarket UCAs would do more harm than good on my setup. It's a '15 TEP, not sure if there's any difference with other years. I also have no interference at full droop with the stock UCA.

So far as I'm concerned with my particular geometry on my sample, I have no reason to go with an aftermarket UCA unless i go long travel or eventually move up to 34"+ tires. If I do that - I'll be building my own custom setup with a-arms, lower and upper, to relocate the entire spindle forward about 1" and probably outboard by 1.25" with new shafts so it matches a rear spacer but has a better scrub radius to avoid rubbing. That combination should fit 35's with front bumper trim only and 1.5-2" lift. But that's down the road and likely not ever going to happen unless I sell my FJ40 and buy a commuter car. I love the look of @marshal 's but it's not really practical for me on my daily driver. For now - the stock uppers work fine for me and my 285's. I understand that they don't for some others. Maybe it's just luck of the draw on the little manufacturing variances that add up to needing or not needing UCAs.

Im on Radflo 2.5 Suspension setup with 285 on TRD Pro Rims and Spider Trax 1.25 Spacers. No issues here ;-)

its not really practical at all tbh. 35's are kind of a waste without long travel front and rear. 285s are plenty of tire

I'm on a 2015 Trail. But I think there's a small difference between a 2.5" fox lift and a 1.75" Bilstein 5100. What's the lift height on the lowest setting??