2016 4Runner SR5
Senior Member
I don't love that the Dobinson arms don't have grease zerks though.........
... It's a real tough decision for me between the Dirt King arms and the JBA arms.
Has anyone had issues with the ball joints on the JBA arms coming loose? They use a nylock but it's pretty useless considering the bolt is so short. Nylocks require 2 threads minimum protruding past the nylon section to work the way they should. This is one of my only concerns with the JBA arms. It's a real tough decision for me between the Dirt King arms and the JBA arms.
Has anyone had issues with the ball joints on the JBA arms coming loose? They use a nylock but it's pretty useless considering the bolt is so short. Nylocks require 2 threads minimum protruding past the nylon section to work the way they should. This is one of my only concerns with the JBA arms. It's a real tough decision for me between the Dirt King arms and the JBA arms.
No issues with mine and I have over 4000 miles on them. I have 5-6 threads showing with mine all tightened down. I was weary about it at first, not using a cotter pin or anything. It's all held up great though.
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Damn man, the DK's are nearly twice the cost of the JBA's.
I'm talking about the 4 bolts that hold the ball joint to the arm, not the single nut that holds the ball joint to the spindle.
Difference between the 2 is 100 bucks
What is the value of a heavy duty UCA? Are people bending or breaking their UCAs that aren't made of boxed 1/4" plate?
I'm aware of only one OEM UCA ever having a failure and it was the result of something like 10,000 race miles on a Land Cruiser 200 with 37" tires in the 2016 Baja 1000. It's the closest analog I know of. Has anyone ever bent or broken one on a 5th gen? Is there a reason for wanting something stronger?
From the folks at JBA below:
Whats the difference between the JBA STD and JBA HD Toyota UCAs - JBA Offroad
Went Dobinson as they were virtually maint free (sealed ball joint) and rubber bushings.
Install was pretty easy with a BJ press and all. At the end of the day, if a new BJ is needed its easy enough to do.
Also helps that I got a great deal on them too!
My bad, was looking at the standard JBA's.
:doh:
Looks like mostly marketing to me. The loads on the UCA are small by design. But I guess that's why I'm asking. If no one has ever bent or broken one - maybe it's not necessary to reinforce them?
Edit: after some searching - it looks like there was a series of the Light Racing UCA's that were prone to failure in the same way. The failure mode seems to be limited in examples I can find to the heat affected area of the bushing sleeve flexing and ultimately fracturing.
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Though I would agree that JBA has their fair share of marketing (as does everyone else), I have seen a far higher ratio of SPC issues as apposed to JBA A-arms/UCA's issues... in fact I have yet to see a JBA A-arm major failure yet on this forum. With regards to the picture you referenced, how is heat a factor in the failure of that UCA? Can a rubber bushing cause enough "heat" to cause this type of failure?? This doesn't add up....
New to the 4Runner world but not Toyota. Just bought a new 2018 TRD Off-road that the dealer had installed a spacer lift on with 285/75s on aftermarket wheels.
It still has the stock UCAs on it so I had them put on the alignment rack to double check the alignment. Best caster they could get is 2 degrees.
Will any of these fixed UCAs (Icon, JBA, etc.) get me to 3.8 - 4.0 degrees or do I need to go for SPC arms with the adjustable ball joint to get 3.8 - 4.0 degrees of caster?
Thanks,
Mitzer