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I picked up some nice plated Rancho radius arms from a member here. These are the older straight versions. I have previously installed 2.5" Eibach coils on my Bronco, had it aligned, and it was decent. I installed the Rancho arms today, using the 15" back number for the radius arm mounts. Now that it is all done, it appears the tires are further back in the wheel well, and the front shocks are angling rearward as well. I was very careful with my measurements, is this normal? Could this be from the 2.5" lift and eccentrics while the Rancho arms are built for 4" of lift? I am not looking forward to removing and reinstalling the brackets in a more forward position, and am not really interested in lifting it higher. What happened here?

My tire and shocks also share a similar angle......it's slight. I've been running it like this for a year with no problems as a daily driver and weekend wheeler. Also when the axle uptravels it moves forward in the wheelwell slightly

The tire will travel closer to the firewall (inwards) as it travels towards bump. I would take the coil out and cycle suspension. Look for critical clearance issues, such as the Blower box. If possible move the axle and radius arm bracket further frontwards. If you are using stock fenders and fenderwells, turn your tires left to right when at full bump, you more than likely if you are too far back it will contact the lower fender at the bottom of the door jam if you're running 35" tires.

I am running worn down 35" BFG at's now, it does not seem to rub anywhere (except on the radius arms). With new tires, it will probably hit. With only 2.5" of lift, the radius arms are level at ride height. I think having it aligned will move the tires slightly forward, as the eccentrics were rotated to restore caster with the stock radius arms and lift. With the castor correction built into the rancho radius arms, the current caster is certainly far too much. The shock angle thing is still weird though, but does not seem to affect anything. That said, I think I would still like to have the whole assembly 1" further foward, as that would put it back to "stock". I think 14" would have been much better for this truck rather than the 15" back I used.

Get the tire as far forward as you can if your going to move the radius arms.

How much caster is "way too much caster"???

I actually just installed my rancho straight arms about two weeks ago. I tried cycling numerous times with the 15" measurement and I could never make it work. I settled on 14.5" and it worked perfect. I'll get you some pictures if you think it would help.

I ended up moving the brackets to the forward bottom hole I drilled. This is 1.5" closer to the front of the Bronco. The tires are now slightly ahead of "center", and there is a little more clearance for the tire's now. So instead of the radius arms being mounted 15" back, they are now set 13.5" inches back. It looks good, and seems to work well too. I don't plan on doing a lot of high speed off roading with the hubs locked, so I hope the slight push forward will not hurt the u-joints.

You could call (maybe it's on their website) Rancho and get the installation instructions. I'm sure they have a specific measurement for you.

FYI: Here are the downloaded instructions. Step 12..... move 15" from original location.

http://www.gorancho.com/assets/instruct ... 88023b.pdf

Thank you for all the help. Yes, it looks like 15" is the standard for the Rancho arms. I'm not sure if it is due to my 2.5" of lift, or what, but that was too far back. I like the 13.5" back that I ended up using. I just had it aligned today, and it rides SO much better than it did with the stock radius arms.

I used the 15" measurment with my 4" lift.

Wishing I had done 14 inches now, as I rub the back of the fenders a bit at bump, but have clearance up front.

Glad you got it figured out and it works well for you.



although it looks pretty decently centered when stuffed and drooped

Mine is set at 15'' amd it works bitchin..