What to change on a 2025–2026 Ram 1500 RHO, in the order we would do it: lift, billet front end, bump stops and limit straps, rear suspension, then armor and bed storage.
The Short Answer
Start with ride height: a front leveling collar with a rear spring spacer, or Geiser springs front and rear. Then the front end: billet upper control arms, billet tie rods and billet top hats. Then control: rear hydraulic bump stops, followed by the front limit strap and bump stop kit. Then the rear: billet or fabricated rear arms and an adjustable panhard bar. Then protect it: underbody skid, rear diff skid, shock skids and shock guard mud flaps. Every FMI part here is built for the 2025 and newer Ram 1500 RHO.
The Ram RHO Build Path
Ride Height
A front leveling collar plus a rear spring spacer, or Geiser springs front and rear. This sets the stance and how much of the shock you use.
Billet Front End
Upper control arms, tie rods and top hats. Serviceable joints replace the factory rubber and the parts most likely to wear or bend.
Bump Stops and Limit Straps
Rear hydraulic bump stops first, then the front limit strap and bump stop kit. They protect everything from steps one and two.
Rear Suspension
Billet or fabricated rear arms and an adjustable panhard bar, plus fabricated front lower arms.
Armor and Bed
Underbody skid, rear diff skid, rear shock skids, shock guard mud flaps and bed organizer panels.
Ram RHO Lift and Leveling
Front Leveling Collars
Want to keep the factory springs and shocks? An FMI collar installs under the factory spring and adds preload to raise the front. It comes in 1.5", 2" and 2.5". The 2" and 2.5" kits include the adjustable ride height sensor connector rods the RHO needs above 1.5". Machined in-house in raw billet or black anodized. For how collars work, see Lift and Leveling Collars: How They Work.
Rear Spring Spacer Lift
The billet rear spring spacer plates sit above the factory rear spring and add ride height and preload. It is about getting the rear height back, especially with a loaded bed. A spacer does not add wheel travel. Anything thicker than 3/4" requires the FMI rear bump stop kit, and do not go past 1.75" total or the rear springs can bind.
Geiser Front and Rear Springs
Want more lift, or new springs instead of preload? The Geiser spring kit gives the RHO about 3" of front lift and 1.5" in the rear with progressive-rate springs. The front goes from 920 lb rising to 1,000 lb after the first 2" of travel; the rear from 240 lb rising to 310 lb.
| Option | Lift | Good to know |
|---|---|---|
| 1.5" front leveling collar | 1.5" front | Keeps factory springs and shocks. No sensor rods needed. |
| 2" front collar kit | About 2" front | Includes ride height sensor connector rods. |
| 2.5" front collar kit | About 2.5" front | Includes ride height sensor connector rods. |
| Rear spring spacer kit | 3/4" to 1.75" rear | Over 3/4" requires the FMI rear bump stop kit. |
| Geiser front & rear springs | About 3" front, 1.5" rear | Replaces the factory springs front and rear. |
Billet Upper Arms, Tie Rods and Top Hats
Billet Upper Control Arms
The FMI RHO upper arms are CNC machined in-house with 7/8" FK rod ends at the frame and a 1.25" FK uniball at the spindle. Replacing the factory rubber bushings tightens up the handling, and the rod ends adjust for caster and camber. When a joint wears, you replace the rod end or uniball, not the whole arm. They bolt to the stock spindle and include wheel position sensor mount plates. Raw, black, FOX orange or blue. More on why in Upper Control Arms: Caster After a Level.
Billet Tie Rods: Half Kit or Full Kit
The half kit moves the outer joint to a 7/8" FK rod end and keeps the factory inner tie rod. That keeps load out of the steering rack, leaves a field-serviceable link, and clears any front shock. It is shared with the TRX, since they use the same steering parts. The full billet kit replaces the whole assembly for maximum strength; it is designed around the stock front shock, so check clearance if you run aftermarket shocks. See Why Off-Road Tie Rods Bend.
Billet Top Hats
The factory top hat supports the shock shaft with a rubber bushing, a known weak point, especially with aftermarket springs. If it fails, the shock can drop out of the spring bucket. The FMI billet top hat uses a serviceable FK uniball and installs at stock ride height.
RHO Bump Stops and Limit Straps
Rear first. The RHO rear hydraulic bump stop kit uses a 2.5" diameter bump stop with 2.5" of travel and installs in the factory spring buckets with minimal modifications. It also works with the rear spring spacers.
Then the front. The front limit strap and bump stop kit works with the factory lower arm. The 12" limit straps stop the shock from being the thing that stops droop, and the bracket has a bump pad built in for a 2.5" front bump stop. It is a must if you run aftermarket springs. The front bump stop mount welds to the frame, so have a qualified fabricator install it. Background: What Is a Bump Stop? and What Do Limit Straps Do?
RHO Rear Suspension and Front Lower Arms
Rear Arms
Two ways to go. The billet aluminum rear arm kit replaces the upper and lower arms with billet arms on 1" FK uniballs, with a 17-4 stainless post on the upper arm for the suspension travel sensor. Uppers and lowers are also sold separately. The adjustable fabricated rear kit replaces the upper and lower arms and the panhard bar in 4130 chromoly. Getting rid of the rubber bushings makes the truck more predictable and limits the flex that turns into wheel hop. It works with stock shocks and springs.
Adjustable Panhard Bar
Change the rear ride height and the axle shifts sideways. An adjustable panhard bar re-centers it, in heim joint or Johnny Joint. The billet arm kit does not include one, so add it if you lift the rear. See Adjustable Panhard Bars.
Fabricated Front Lower Arms
The RHO fabricated lower arms are 4130 with a 1.5" uniball at the spindle and 1" uniballs at the frame, built-in steering stops, and mounts for a 3" bypass shock. They work with the factory coil over. The upper bypass shock mount for the RHO is still in development, and the arms need added parts to connect to the factory sway bar.
RHO Skid Plates and Protection
Underbody Skid Kit
Four pieces of 3/16" aluminum covering the front diff and steering area, transmission and transfer case, plus a transmission cross member support.
Rear Diff Skid
Covers and supports the lower back plate so rocks cannot catch the diff cover and pull the seal loose.
Rear Shock Skids
3/16" steel guards that protect the bottom of the shock and the rear axle mounts from rocks.
Shock Guard Mud Flaps
18" by 7" flaps that shield the rear shocks from front tire roost. A popular pair with the shock skids.
Bed storage: the RHO bed organizer panel kit covers the bed wall, including the cleat area, with steel grid panels for power tanks, jacks and other gear.
RHO Parts From the Build
Built for the 2025 and newer Ram 1500 RHO.
Every RHO Part, by Step
| Step | Parts |
|---|---|
| 1. Ride height | 1.5" collar, 2" collar kit, 2.5" collar kit, sensor connector rods, rear spring spacers, Geiser springs |
| 2. Billet front end | Billet upper control arms, half tie rod kit, full billet tie rod kit, billet top hats |
| 3. Bump stops and straps | Rear hydraulic bump stops, front limit strap and bump stop kit |
| 4. Rear suspension and lower arms | Billet rear arm kit, billet uppers, billet lowers, adjustable fabricated rear kit, panhard bar, heim, panhard bar, Johnny Joint, fabricated lower arms |
| 5. Armor and bed | Underbody skid kit, rear diff skid, rear shock skids, shock guard mud flaps, bed organizer panels |
Building a TRX instead? See The Best Ram TRX Upgrades.
Ram RHO Upgrade FAQ
What is the best first upgrade for a Ram RHO?
Ride height. A front leveling collar with a rear spring spacer keeps the factory springs and shocks. For more lift, Geiser springs give about 3" front and 1.5" rear.
Why does a RHO lift over 1.5" need sensor rods?
The RHO's electronics do not tolerate more than 1.5" of front lift unless the ride height sensor location is corrected. The FMI 2" and 2.5" collar kits include adjustable connector rods for that.
Does a rear spring spacer add wheel travel?
No. It adds ride height and preload, not travel. Over 3/4" requires the FMI rear bump stop kit, and do not go past 1.75" total.
Half tie rod kit or full kit on a RHO?
The half kit clears any front shock and keeps load off the steering rack. The full kit is the strongest option and is designed around the stock front shock. The RHO and TRX share the half kit.
Do I need billet top hats?
If you run aftermarket springs, they are cheap insurance. The factory top hat's rubber bushing is a known weak point, and a failure can drop the shock out of the spring bucket.
Does the front bump stop kit bolt on?
No. The limit strap brackets clamp to the factory lower arm, but the front bump stop mount welds to the frame. Have a qualified fabricator install it.
What years does this cover?
FMI RHO parts are built for the 2025 and newer Ram 1500 RHO. The collar kits list 2025 and 2026.
Planning a RHO build? Call the shop and tell us how you use the truck.