Toytec Ultimate Lift Kit: UCAs or not to UCAs...
- Thread starter W8kbrder
- Start date
Canazes9
New member
I've got +2 on my wife's 4 runner with stock UCA's. 2.125" lift on the front of hers and it drives quite nicely, no wandering.
David
ColoradoFrosty
New member
On my stock UCA's and a 3" lift they were able to get the caster at 2. (I know you guys are discussing a 2.5" lift here...)
When Slee did my lift I asked about going with some LR UCA's. At the time they weren't recommending or saw the need, however after more experience with the 5th Gen, they do now.
So I drove around for a year with the stock UCA's and was never really happy with the nervous and wandering behavior at highway speeds and windy roads. It tracked fine, but steering was just twitchy and you had to always be very attentive. I have driven lifted CJ5's in the past which were much worse... this wasn't as bad so I figured it was just something to deal with.
I don't drive the 4Runner much in winter, I use my old Tundra. But with the nervous behavior on the 4Runner I would have been sketched out on icy mountain roads here in Colorado.
So then here in August on the way home from a friends after a couple beers, at 2:30am I got pulled over by the local sheriff that said I was weaving. Please note that I was not under the influence and passed all the roadside tests. However the officer was not very understanding on my explanation on the 4Runners handling performance. It was an eye opening and scary event that made me realize it was time to get it done and fork out the additional $800 for the parts/install/alignment.... that I should have done along with the lift.
So sunk the money and just got the LR UCA's installed on Wednesday. Slee balked at putting the caster up to 4 and recommended to not go that high. Specs are 2.0-4.0 and they just didn't want to go to 4 like I was asking. I trust the guys at Slee and went with ahead with their setting at 3.5 caster.
The truck drives much better now but I am wondering if I should go back and get them to do the 4 caster. Like I said it's much better now... but from everything I see if I go to 4 things will be dialed.(?)
I don't mean to hijack here but it's pertinent when installing aftermarket UCA's. And since I find the T4R 5th Gen knowledge base is higher here on the forum than at many good shops, should we go to 4 caster despite warnings from what well respected off-road shops might tell us?
So the question: For LR UCA's on a lifted 5th Gen is 3.5 caster good, or will 4/4+ be optimal?
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Jeremy556
New member
4, or more is better.
It will push the front tires into the front of the wheel well, which can easily be fixed by moving the fender liner forward and/or modifying the fender liner. Conversely, it will help to keep your tire off the body mount. The only real negative you might encounter with higher caster is slightly increased steering effort at higher speeds.
Mine was on the low end of specs when stock and it drove like crap. I had it aligned and they got it to about 3.5 and it was much better. After lifting, it took a few shops to do the job properly. Initially around 2 degrees, it again drove like crap. Once it was finally done to a little over 4, it drove great again.
Lots of people have gone through this and I have never seen anyone on these forums (or Taco forums before this) who had any problems, or regretted pushing castor to the high end, or beyond spec. A few guys here are running considerably above 4 and have no issues.
It will push the front tires into the front of the wheel well, which can easily be fixed by moving the fender liner forward and/or modifying the fender liner. Conversely, it will help to keep your tire off the body mount. The only real negative you might encounter with higher caster is slightly increased steering effort at higher speeds.
Mine was on the low end of specs when stock and it drove like crap. I had it aligned and they got it to about 3.5 and it was much better. After lifting, it took a few shops to do the job properly. Initially around 2 degrees, it again drove like crap. Once it was finally done to a little over 4, it drove great again.
Lots of people have gone through this and I have never seen anyone on these forums (or Taco forums before this) who had any problems, or regretted pushing castor to the high end, or beyond spec. A few guys here are running considerably above 4 and have no issues.
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ColoradoFrosty
New member
Thanks Jeremy... just what I was looking for.
I was however a little perplexed as after the install and alignment, I am now having rubbing issues at the rear wheel well and had to take off the faux mudlaps to prevent a problem. And I am worried about when off-road I'll now have an issue hitting the body mount.
Going from 2.0 with the stock UCA's there was no rub on the body mount... now I am getting it with the LR UCA's at 3.5 caster.
Jeremy556
New member
That is strange. All things being equal it should have moved the center of your wheels forward. Did you put on wheel spacers, or wheels with different back spacing at or about the same time?
I run the same tires on ATX Mojave's which are 8" wide with 4.5" of back spacing. I lost my little mudflaps to rocks before lifting, so can't comment there, but with 4 degrees of caster, the only place I rub at full stuff/full lock is the front wheel liner. There is one little bump in it that I have been meaning to cut or heatgun, but never remember to.
I run the same tires on ATX Mojave's which are 8" wide with 4.5" of back spacing. I lost my little mudflaps to rocks before lifting, so can't comment there, but with 4 degrees of caster, the only place I rub at full stuff/full lock is the front wheel liner. There is one little bump in it that I have been meaning to cut or heatgun, but never remember to.
ColoradoFrosty
New member
Nope. No other changes. No spacers. One thing at a time with this stuff, eh?
And that the wheel center would have been farther forward, that was my understanding as well.
I'll need to discuss with the shop... I am spoke with them this afternoon and am going back next week to go to 4+.
Thanks Jeremy
Scott@Hightech
New member
I think whe i tried to max a truck out it was around 6.5 deg, which is way excessive. We set 4runners to around 4 deg. caster and they Drive great.
Likely what they did was adjust the upper control arm back to get the increase in caster which moved your wheel back in the wheel well,
What i like to so is set the upper joint one notch forward and try to get my alignment within specs that way you have a lot more clearance in the back. the fender liner mod is easy and rather harmless so its much less painful if trimming is required
Ducmonsta
New member
[MENTION=65614]Antman[/MENTION] what Scott means to say is around +2* WITHOUT UCAs.
Good thing he's a good tech because his reading skills are lacking.
Scott@Hightech
New member
Oh wow, yeah totally missed that, WITHOUT UCAs you can get +2 maybe +2.2 But camber is usually around +.5 positive, which technically is acceptable but with larger tires you want it close to 0.
ColoradoFrosty
New member
Scott you mentioned to "set the upper joint one notch forward". So I get this dialed on my next attempt this week, are the notches numbered or is there a desired notch setting to initially work from?
Scott@Hightech
New member
They aren't numbered and its not really "notches" its a octoganal opening and you can set it which ever direction you want. If looking at the control arm installed from the wheel opening. The Flat edge should be facing outwards which puts the ball joint on the inside(its offset). Then rotate it one notch so that the ball joint is closer to the front of the truck. This is where i START!!! Then i attempt to Dial the caster in with the LCA cams. THIS doesnt work on every truck, they are all different. some have it one notch forward on one side and centered on the other side. It all depends on the truck.
That sounds right. This paragraph from a racing book I have should explain why you are experience this:
Adjusting Caster
To adjust the amount of caster in each wheel, you will need to move the upper ball joints fore or aft. To increase the amount of positive caster, move the top ball joint toward the rear of the car. Some cars have slots cut into the upper chassis mounts for this purpose.
So, you've moved the upper ball joint toward the rear of the vehicle to gain more caster. If the lower control arms are maxed out, the only way to gain caster is to add new upper control arms that move the ball joint back toward the rear of the vehicle. Moving this pivot point (upper ball joint) toward the rear of the vehicle will bring your tire closer to the body mount. I have 285/70's as well and have struck the body mount maybe 2 times while off-roading in the past. I'm not concerned, but would do a BMC if I was to go with bigger tires.
Ducmonsta
New member
While this is true, the point of adj cont arms for our trucks is to max out the lower control arms forward. Many shops don't bother with doing this first. Adjustments should now be made with only adjusting the uppers. Fine tuning is all that should be done with the lowers.
