fj80 RADIUS ARMS (2 Viewers)
- Thread starter lacresta
- Start date
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Your getting there, looks like you need caster bushings, caster plates, or caster correction trunnion bearings.
Personally I would recommend the trunnion bearings 1st and plates 2nd.
- Joined
- Sep 9, 2004
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- Boise - Idaho
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- www.snlandcruisers.com
Just got these in today from Australia.
People have asked in build threads or on IG why use something other than Delta?
I have ran;
Delta
Blackhawk
JMacX
Superior
To reply to the Delta question, #1 I like trying different products and #2 we have been able to get Aussie radius arms in 1-2 weeks landed at the shop. Not much wait.
Cheers
People have asked in build threads or on IG why use something other than Delta?
I have ran;
Delta
Blackhawk
JMacX
Superior
To reply to the Delta question, #1 I like trying different products and #2 we have been able to get Aussie radius arms in 1-2 weeks landed at the shop. Not much wait.
Cheers
- Thread starter
- #84
great looking arm, how much are they shipped her to US? what deg of correction do they offer? I went with the superior standard arms and have had great results. got them in 1 week no excuses and great CS. just could not wait on Delta, I have had my share of problems getting Delta products.Just got these in today from Australia.
View attachment 3062802View attachment 3062808
People have asked in build threads or on IG why use something other than Delta?
I have ran;
Delta
Blackhawk
JMacX
Superior
To reply to the Delta question, #1 I like trying different products and #2 we have been able to get Aussie radius arms in 1-2 weeks landed at the shop. Not much wait.
Cheers
They offer a set for a 2" lift and a set for a 3"-4" lift.
I like the looks of these arms. I am putting them on my list for when I re do the suspension and go for 37"s.
I really like how this company states that the optimum caster for non oem vehicles is 4-6 degrees. It drives me nuts how everyone seems to think that oem factory specs are adequate for a rig with larger than oem tires.
This makes me think you would get slightly more caster correction out of the jmacx 2" arms than other companies 2" arms or caster correction methods for 2" lifts.
I'm by no means an expert on suspension--but isn't the idea to bring it back to stock caster (3-4 degrees IIRC) after the sprung weight is lifted? Again no expert here, but I'm having a tough time seeing how taller tires affect caster, when all they do is raise the axles. Or is that not what you're saying?
Somewhere on Mud there are photos of said failure. Ah--post #41.
The taller tires don't change caster, but the bigger tires create more force on the steering than oem tires so oem caster specs are not adequate.
Think of it like this. Proper caster helps keep your tire from wandering and following when your tire hits something like a bump, ridge, or rut in the road.
Toyota called for the 3 degree spec to keep an OEM size tire tracking straight.
When you have taller heavier tires than oem the tires have more contact on the road and they impart more force on the steering components at the same time they also have more grip that wants to follow the imperfections in the road more than an oem size tire.
So when your driving down a dirt road and your 35" tires hits the edge of a rut you have more force acting on the tire and the tire wants to follow the rut more so than an oem size tire would.
So because a larger tire creates more force on the steering than an oem tire than a rig with larger heavier tires needs more positive caster than oem specs.
When I lifted my first cruiser and got the caster spec to 2 degrees along with installing heavy duty steering linkage, replacing all the bushings, and a new steering stabilizer the rig was way worse at trying to drive itself into ruts or drifting on the highway if I hit a bump or the ridges in the highway.
Than I installed trunnion bearings for more caster correction, got the caster to 4.5 degrees and it drove like it did with oem size tires. The extra caster kept the rig from trying to steer itself into ruts. When I would drive down the highway I could shift in the lane and ride on top of the ridges in the pavement and the rig would still track straight instead of trying to drive back down into the low spots of the pavement.
I don't know if my explanation helps but it makes sense to me. Plus I have verified this theory with a few experts on lifting 4x4 vehicles and doing custom suspension stuff.
The oem caster spec was engineered for an oem size tire. Bigger tires create more steering forces because they weigh more, they are taller and input more leverage forces on the steering, and they have more contact/ grip with the road. Therefore they need more caster than OEM specs.
The only photos I have ever seen of this failure is where the guy actually notched the arms, he didn't gracefully clearance the arms with smooth lines and skillful grinding lol.
That would be post #41 et seq?
It's more of an across the board, any and all solid axle vehicles behave the same with regard to caster. Most have 4 degrees stock. 4-6 is pretty standard for anything with bigger tires. I would imagine this has been hashed to death over time here with all the caster/lift issues. The only real concern is balancing enough caster with not going too far and needing a DC front shaft with a <3" lift.
So don't rely on damper alone to address this? Also--what kind of tires and lift were you running? I'm planning 2" 33-35s.
I was running a 2" old man emu lift with 35"s on that rig. Plenty of people run 35"'s with 2-3 degrees with no issues. It's definitely do able especially if everything else is up to par.
But 4 - 6 degrees will make a noticeable difference. Especially on high speed gravel roads with ruts from other people driving when the road was muddy.
yep, I totally forgot that was already covered in this thread lmao.
Yes, very true. I should have mentioned this. This is why I am a big fan of trunnion bearings for caster correction because they don't affect driveline angle. A combination of the trunnion bearings and caster plates, drop brackets, or custom arms is the way to go.
Other than that the best solution is a part time kit.
Was thinking of picking up a set of these or the Blackhawks since they resemble the factory arms.Just got these in today from Australia.
View attachment 3062802View attachment 3062808
People have asked in build threads or on IG why use something other than Delta?
I have ran;
Delta
Blackhawk
JMacX
Superior
To reply to the Delta question, #1 I like trying different products and #2 we have been able to get Aussie radius arms in 1-2 weeks landed at the shop. Not much wait.
Cheers
Last edited:
Check @SNLC's odd caster results with those...
Just read that, interesting. Also seen that they don’t offer factory bushings just there own version on the Blackhawks
Box Rocket
SILVER Star
The "lifetime" bushings in the Blackhawk arms look pretty good IMO. But you could always put factory rubber bushings in the arms. They are made to accept factory bushes.
How much were the JMACX shipped to your location and any results and impressions you can share after install?Just got these in today from Australia.
View attachment 3062802View attachment 3062808
People have asked in build threads or on IG why use something other than Delta?
I have ran;
Delta
Blackhawk
JMacX
Superior
To reply to the Delta question, #1 I like trying different products and #2 we have been able to get Aussie radius arms in 1-2 weeks landed at the shop. Not much wait.
Cheers
