Please note: Due to the huge popularity of this item, Depending on color these may be on a delayed shipment of 2-4 weeks. You will be emailed with an estimated ship date after your order is placed.Â
Product Update: June 2020 – We are now separating out our FSB and RBV long arm kits. Please see #5352 and #5353 for those systems. These are not compatible with the 5225 shock towers.
We originally designed this long arm for the ’78-’79 Big Bronco, Our proven Long Travel Extended Radius Arm is Designed for rugged off-road use while enhancing drivability. Fabricated out of 2″ diameter, heavy-wall DOM at a whopping 5/16″ thick! For strength and safety, we designed a separate cast steel head unit to mount to the C-wedges on the axle with your original C-cap or our new ones sold separately. These arms are 10 3/4″ longer than a ’66-’79 Bronco arm, moving the pivot point farther back. This vastly improves suspension travel & articulation but it doesn’t stop there. These arms also improve handling & control for on-road driving.
- Proven Design since 2001
- Bolt-in C-Channel Frame Mounts
- 10 3/4″ longer than stock
- Built-in 4.25 degrees of added caster
- Backed by the best customer service in the industry
- Big Tires? Due to the offset built into them, that’s what these arms are made for
- Needing more articulation, more flex? Our extended arms will give you the most of any arm on the market
- Strongest extended radius arms available
- Made from 100% brand new American Materials
- Comes powder coated with all necessary hardware
- Just say no to janky designs and core charges!
Fabricated from all new materials; no core charges, no cutting or welding to 40 to 50 year old cast arms. Built-in caster means better alignment and handling. A tight to the frame rear mount holds the arm with a high quality 1″ bore Teflon lined and lubricated Rod End, keeping it closer to the frame for improved ground clearance and break-over angle. Tons of travel, a tighter turning radius, better ground clearance and improved handling all in one product! Includes arms, head units, rod ends, frame mounts, bushings, and all necessary mounting hardware. Requires at least a 4″ suspension lift for ’78-’79 Ford Broncos. C-bushings are sold separately due to vehicle variations and lift height. This kit includes arms, cross member brackets, specially designed frame brackets with a backside reinforcement, and riser brackets for the brake lines. The arms are the same proven design that we’ve been selling for years! Combine with our Cast C-Wedges, C-Caps, and Spacers to swap in a new Dana 44 or Dana 60! Note that a High Pinion 44 or 60 needs about 8 degrees of caster, 5-6″ lift on this axle will utilize the 4-degree C-Bushings #6004. Any more lift then that use 7-degree Bushings #6007. The caster numbers can be adjusted on all axles depending on what angle the C-wedges are welded onto the axle. Please note these are heavy-duty, they come in two packages totaling 121lbs!
Want to know what’s involved for installation? Download instructions here.
FAQ:
Q: What is a radius arm and why should I upgrade to the James Duff Long Arm?
A: James Duff Inc. has been the leader in Bronco off-road suspension for over 20 years. Why you ask? Our Extended Long Travel radius arm matched with our long-travel suspension systems allow the Bronco to traverse over almost any terrain. Designed and manufactured by James Duff Inc. It is a tubular & plate steel design that utilizes a secondary cast steel component called a head unit to mount it to the Bronco. This two-piece design not only makes the install easier but also incorporates 4.25 degrees of added caster. When it comes to lifting Bronco front suspension, CASTER IS KING! This extended length radius arm is not only MASSIVELY stronger and offers MORE caster than the OEM design but it also allows up to 37″ tires to fit w/o sacrificing the Broncos tight turning radius. This arm is a direct fit for all dana 30 & 44 axles made from ’66-’79.Â
Q: What axles are these arms compatible with?
A: Our radius arms are designed and engineered to work the factory-equipped Dana 30 or Dana 44 front axle on the Early Bronco Platform. They will also work in the Full-Width High Pinion Dana 44 that comes installed in the ’76-’79 F-150 4×4 or ’78-’79 Big Bronco. If you are wanting to pair them with another axle such as a Dana 60 or Super-Duty 60 then you must ensure that the axle uses the ford style axle wedges or you must grind off any brackets that use a different style attachment point and weld on the wedges we sell.Â
Q: I ordered these but they are missing the part to bolt on the head unit to the axle!Â
A: Correct this kit doesn’t include new c-caps. You must select that option at check out or reuse your factory-equipped C-Cap. Keep in mind we offer the optional c-cap add-on in color-matched powder coat or bare if your C-Caps are in rough shape.Â
Justin Scoggin (verified owner) –
Excellent quality parts and fast shipping, even were able to answer all the questions I had for them
Greg McQuiston (verified owner) –
Put these radius arms on my 92 F150 Flareside SAS. Well made and heavy duty. Straight forward installation. Would have given 5 stars but the 1/2 inch wide spacers had large burrs in the inside and didn’t fit over the 1 inch bolts.
Chris Mann –
I ordered the extended radius arms for my ttb bronco. I was extremely please with them. so, now that I’m doing a sas to the same bronco it was a no brainer on getting these. shipping was fast.
Kevin Smith –
This is a very nice product! The quality of the materials, machining, welds, and shipping packaging are better than most other products. The paint application is a 9/10, but could there be a paint product that could be more durable? I could see it getting scratched up quickly on the trail.
best regards,
Kevin Smith
Dan Bastian –
Did a SAS on my Bronco II and James Duff in my mind is the only option and way to go. Super smooth and crazy amount of flex capability. I out wheel jeeps on a regular basis now. Quality and strength 2nd to none!
Karl Goulding –
Excellent product. Only thing i wish i would have seen was better packaging for the bolt/nut/washer bag/kit. as it popped opened during shipping ans was everywhere in the box. Will buy from again. next item will be coils and track bar mount and bar.
Rob Applegate –
Parts came in with a little bit of powder coat damage, but James Duff customer service was professional and very helpful in making everything right.
Daniel Travis –
Ordered a set of long travel radius arms for my 79 Bronco, haven’t installed yet but James Duff called me to go over my order before shipping to get everything right, they even recommended other parts that they offer that would make my Bronco the best it could be! Can’t wait to install everyrhing and represent a geat company!
Thank you for making a great buying experience and taking the time to get me what I need the first time!
Colin Odonnell –
Got my long arm kit for my 78 f150 i have yet to install it but i can already tell that these parts are nothing but quality thank you james duff
Richard Burr –
use caution when adding these to your bronco if you have a big block 429/460 with L&L fenderwell headers . mine do clear but with little to no room for the headers . i have a 4″ lift 2″ body lift they havent hit yet but i havent 4 wheeled it hard yet i only rated them as good till i find out if they will hit when it flexs other than that they are excellent !!!!
Masters –
The lady that called me about the shipping payment is a wealth of knowledge. She really impressed me. As far as the order goes, the boxes are junk. They were completely ripped to shreads when received. The contents were nicely wrapped and protected the hardware. I would definately order this again soon as matter a fact. We will be doing the same install on a Taco.
Preston Hicks –
This kit will not simply bolt up!!! I had to bend my radius arms in another 20 degrees to get it to lineup with the bracket!!! Don’t get me wrong this is great quality and very heavy duty I love the product and the quantity but make sure you talk to at least 3 people before they ship your order! I was supposed to get midnight black after we switched it from silver vein and I still ended up with silver and I literally went over the changes 3 times! I waited almost a month and a half for my shipment and still didn’t get the right powder coat color and literally almost had to sell my radius arms because the guy told me on the phone they would work and literally they didn’t until I put them on a pipe bender!
Francis Alvarado –
Product came when promised, parts are nice and beefy looking and instructions seem clear enough. Not sure why this can’t be packaged into a kit for IFS swaps. Will do business with you again in the future
Cody Bouma –
These arms surpassed my expectations, the powder coating is clean and durable and they are very heavy duty. You can really tell they put alot of time, money, and effort into making these work and last
Jeremy Wilkening –
What on-line seller these days says, “we will contact you to discuss your order and get shipping charges approved”? Duff Tech steered (no pun intended) me in the right direction, supplying the correct C bushings, despite how I mis-interpreted information on the website. Thanks Guys. My project Bronco Billy is going to be BadAss.
Ricki Young –
Matt Blazosky –
Tried using stock radius arms off a 78 truck didn’t work out and didn’t wanna half ass it. Bought these and worked perfectly thanks
Ryan Coltrane –
Purchased this long arm kit for my ranger and was amazed at how fast it got here. Also looks amazing. Highly recommended
Chad Roelo –
Looked great when received also answered all my questions Great Job Thanks !!!!!!
Kevin Driver –
Doing a SAS on a 95 ford bronco and everything came in great shape from James Duff. The directions were all right on point. The quality of parts is amazing. I would definitely suggest them to anyone trying to convert to straight axle from ifs.
richard wilson –
The extended radius arms fit perfectly….. Thanks for a good looking and super tuff product…..