RPM Arrma Kraton 8S Rear Suspension Arms (2)
About this part
RPM Arrma Kraton 8S Rear Suspension Arms are a heavy duty upgrade for the Arrma Kraton 8S & Outcast 8S models. These 26 lbs, high-flying, dirt shredding, jump-killing machines are true monsters. If your A-arms aren’t up to the abuse this massive rig can dish out, look no further than RPM. These replacement rear A-arms are designed with the backyard basher in mind and can handle some serious abuse and come back for more.
RPM rear A-arms have a triple beam style construction designed to spread impact energy across all three beams. Each beam’s cross-section is a whopping 5/8” (15.8mm) tall x 3/8” (9.5mm) wide. These massive beams reduce unwanted flex during normal suspension movement, yet allow impact-absorption during those not-so-perfect landings and crashes. RPM also moved the inner cross brace away from the chassis, eliminating the droop stop entirely. While this may seem counter-intuitive, the RPM test truck chassis was bent at the droop stops, clearly illustrating that extreme impacts were too much for the chassis plate to handle. After all, there’s nothing worse than a bent chassis.
Made in the USA from RPM's trademark blend of ultra durable materials, you can’t go wrong with RPM!
- Sold in pairs
- Replaces stock ARRMA ARA330590
- Optional Mud Guards also available (RPM80642)
Reviews2.8 · 4 reviews
I have used rpm arms for years, and never had any real issues. The rpm arms for the kraton 8s do not fit properly. The shock ends do not fit into the arm unless you shave some plastic off the arm. You have to drill out the hole for the sway bar screw, because the hole is to small. Good luck getting the screw back out in the future,because the back side of the screw bottoms out before the threads can grab. A 20 minute job took me 2 hours, because of the fitment issues. Save yourself time and money, and just buy stock arms.
Arms are better then stock but RPM WILL NOT honor their so called “lifetime warranty“ if the wheels ever leave the ground.
I bought these after shattering a stock front arm from a fairly minor impact. Definitely follow RPM's suggestion to use a thread cutting tap to start the threads for the pivot balls. It will make your life so much easier. As another review suggested, I also needed to use a knife to trim down the inside contact area of the arm hinges where they mount to the hinge pins. Doing this allows them to fit easily and operate smoothly without binding. Also you will need to purchase or fabricate some sort of suspension limit straps as these arms do away with the stock droop points on the chassis. I made my own limiting straps, but there are some options out there for sale. Installing limiting straps with these arms will help your driveshafts and shocks live a longer life. So far I haven't had any issues with these arms other than the minor trimming during install.
Buy these immediately for your Arrma 8s truck! The factory arms are brittle and weak. These also remove a lot of the slop in the suspension.
Reviewers are divided. Two reviewers praise the arms as stronger than stock and as reducing suspension slop, though one says they need fitting work. Fitment is the main complaint: one owner reports the shock ends and sway bar hole required shaving and drilling, adding significant install time. Another reports the arms need hinge trimming, a thread-cutting tap for the pivot balls, and separate suspension limit straps because the stock droop points are removed. One reviewer reports the manufacturer declined a lifetime warranty claim after the wheels left the ground. All reviews concern the rear arms for the Kraton 8S; the sample is small.
- + Stronger than stock arms
- + Reduces suspension slop
- + Fitting issues resolved with trimming
- − Poor fitment out of the box
- − Requires drilling, shaving or trimming
- − Needs separate droop limit straps
- − Warranty claim denied after air time