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  1. Vehicle Suspension
  2. RAS
  3. Leaf Springs and Helper Springs
  4. Towing/Load Leveling
  5. Rear Axle Suspension Enhancement
  6. Standard Duty
RoadActive Suspension Custom Leaf Spring Enhancement Kit
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RAS

RoadActive Suspension Custom Leaf Spring Enhancement Kit

Part Number: RAS29VR
In Stock
$539.00
Vehicle Suspension

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etrailer Installation
We'll connect you with nearby partnered installers who know this exact setup.
2,000-lb Capacity. Convert your vehicle's leaf springs into a mechanically active suspension system. RAS adjusts to your load to level your ride. The system also increases stability, handling, and control by improving traction and reducing sway. Great Prices for the best vehicle suspension from RAS. RoadActive Suspension Custom Leaf Spring Enhancement Kit part number RAS29VR can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.
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  • Reviews (542)
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RAS Vehicle Suspension - RAS29VR

Highlights

  • Custom Fit for Your Vehicle: Mounts to existing attachment points
  • 2,000-lb Load Support: Levels your ride under heavy towing or hauling for safer handling and braking.
  • Instant Stability Boost: Stops sway, squat, and body roll before they start for a more controlled drive.
  • No-Maintenance Design: Once installed, it requires no air checks or adjustments for worry-free use.
  • Stronger Suspension Life: Reduces stress on leaf springs, shocks, and tires to help them last longer.
  • Corrosion-Resistant Build: Epoxy e-coated steel and 800-hour salt spray rating stand up to tough conditions.
Made in USA

Features to know about

Stay Level and Confident: 2,000-lb Suspension Support

Heavy towing or hauling doesn’t have to mean rear-end sag or light steering. The RoadActive Suspension Custom Leaf Spring Enhancement Kit adds 2,000 lbs of support by turning your stock leaf springs into a mechanically active suspension system. It automatically adjusts to your load so your ride stays level whether you’re carrying gear in the bed or pulling a trailer. With the weight balanced front to back, traction and braking stay solid and your truck feels planted instead of wallowing under pressure.

RoadActive Suspension kit installed on rear axle illustrating how it levels the vehicle and improves traction when towing or hauling heavy loads.

Stop Squat and Wheel Hop Before They Start: Mechanically Active Coil Tension Springs

When weight hits the rear axle, this system reacts immediately—no waiting for air pressure or hydraulics to catch up. Variable-rated coil tension springs engage right away to absorb and support the added load, keeping the leaf pack from flattening out or twisting. That quick response stops axle wrap, eliminates wheel hop, and prevents bottoming out so your suspension keeps doing its job instead of fighting the load.

RoadActive Suspension system installed on leaf springs demonstrating prevention of axle wrap and wheel hop for smoother ride control.

Smooth Out Sway and Body Roll: Built-In Stability Under Load

Long highway hauls and mountain curves can make a rig sway or lean hard when the load shifts. This kit reinforces your factory springs to reduce sway, body roll, and that uneasy rocking when a semi passes by. The result is steadier cornering, surer control, and a calmer ride when towing campers, boats, or heavy trailers—without adding extra hardware or friction points.

Set It Once and Drive: Maintenance-Free Bolt-On Design

The RAS unit comes fully assembled and bolts under the leaf spring around the factory U-bolts—no drilling, cutting, or welding needed. Once installed, it’s maintenance-free with no air lines or adjustments to monitor. Durable epoxy e-coated steel construction and corrosion-resistant brackets rated for more than 800 hours of salt spray keep it working season after season without fussing over leaks or rust.

Specs

Weight and Capacity

  • Weight capacity: 2,000 lbs
  • Note: RoadActive Suspension will not increase your vehicle's weight-carrying capacity

Warranty

  • Warranty: 5-Year warranty
  • Money-back guarantee: 30-Day money-back guarantee

4515-R RAS Custom Active Suspension System for OEM Leaf Springs - Rear Axle

Installation Details RAS29VR Installation instructions

This Product Fits The Following Vehicles




Video of RoadActive Suspension Custom Leaf Spring Enhancement Kit
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Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.




Video Transcript for Review of RAS Vehicle Suspension - RoadActive Custom Leaf Spring Enhancement Kit - RAS29VR

Hi, everybody. Andy here with etrailer.com. Let's take a look at this RoadActive Suspension Custom Leaf Spring Enhancement Kit. Now this kit has been designed to fit your 2019 to 2023 Ford Ranger. And on custom fit parts such as this kit, I do recommend taking advantage of our vehicle fit guide here at etrailer.com. Simply input the year, make, and model of your vehicle, and our fit guide will confirm if this will work for you or if we have something comparable that will work for you.

Now, as you probably know, when towing or hauling a heavy load, you may encounter a number of problems that can make your driving experience difficult and even dangerous, such as sway, body roll, or bottoming out. When your truck is weighted down, your factory leaf springs can't counteract those problems to the extent that they are supposed to. The weight will overpower those leaf springs and cause them to twist and even flatten out. So when this happens, they can't support or level or stabilize your truck effectively. Additionally, because your factory leaf springs are passive, they won't begin to tackle the problems, such as sway, until those problems have already begun.

Now this kit is going to convert your truck's factory leaf springs into a mechanically active suspension system. It will actively strengthen your leaf springs for an improved ride quality with or without a load. And this all-in-one suspension system will improve stability, handling, and control. It's going to eliminate axle wrap, wheel hop, bottoming out. And it's gonna reduce dangerous sway and body roll when you're cornering.

This is even gonna help keep your ride level when you're towing or hauling a heavy load. It's gonna help improve traction while braking and accelerating. This does use the variable rated coil tension springs, which will automatically adjust to your vehicle's load. They're going to activate immediately to support extra weight, and then they'll disengage when unloaded, allowing your leaf springs to perform as intended. Now they can be adjusted during installation to help accommodate your towing or hauling needs, and they are independently adjustable for side to side leveling of any off-center loads.

These are gonna help extend the life of your truck's leaf springs, your truck shock absorbers, shackles, and even your tires. These are made here in the USA. They are constructed of a durable epoxy e-coated steel. The corrosion resistant brackets on the ends of each of these units here have a salt spray rating of more than 800 hours. And this is going to be an easy bolt-on installation. What's nice about this kit is there's no drilling, there's no cutting, there's no welding required. And this is going to secure under the leaf springs around the factory U-bolts. And actually I've got an image here that I'll just pop up on the screen there for you, just kind of give you an idea of how these install. So again, they're gonna secure under the leaf spring around the factory U-bolts. And they're going to arrive exactly as you see them here on my table. They're gonna be fully assembled, and the hardware's going to be included. So again, it's gonna be a relatively easy install. These are gonna be maintenance-free. Adjustments and monitoring aren't going to be needed once they're installed. And the weight capacity on these is 2000 pounds. However, I want to make an important note that these aren't going to actually increase your Ranger's load carrying capacity, so you wanna make sure that you don't exceed your manufacturer's weight capacity recommendations for your Ford Ranger. Well, I think that's gonna wrap up our look today. I do hope that it was helpful for you. Again, my name is Andy. Thank you for joining me.

Customer Satisfaction Score:

Ratings & Reviews

4.7

541 reviews
Review sort icon
2,000-lb Capacity. Convert your vehicle's leaf springs into a mechanically active suspension system. RAS adjusts to your load to level your ride. The system also increases stability, handling, and control by improving traction and reducing sway.

by:

I installed the Road Active suspension standard duty kit on my 2017 Tundra. I was hoping for a smoother ride with and without a load and I was not disappointed. I don’t do heavy hauling, just a center console boat that weighs about 3000 pounds with trailer. My truck definitely has a smoother ride. It is especially noticeable on rough spots like bridge crossings, etc. I set the springs somewhere in between the light and heavy settings. I used a quarter as a spacer. It raised the rear of my truck one inch. I definitely recommend the Road Active suspension and etrailer is the best place to buy it.



by:

Overall, very happy with the product. GMC didn't have any way to improve the truck from squatting when I hooked up my trailer. This kit didn't stop the squatting but significantly reduced the bounce on bad dips in roads, bridge/road transitions and bad railroad crossings.



by:

Hands down the engineering behind the product was well executed and would recommend it to anyone who's travels involve pulling any type of trailer. You will feel a much smoother ride even when not pulling a trailer at all.



by:

I received this kit in a very timely manner always do from etrailer have some issues with the instructions that come from roadmaster not a trailer the bump stop spacer didn’t say that you need to use the original bolt from the bump stop so it slowed me down greatly on the install however I took it out on a quick run without a load I do feel that this has made the unloaded ride smoother tomorrow I’ll be taking the trailer out for a bit and we’ll see how it works there and I’ll update this rating.



by:

Made all the difference in the world! Also, easy to install. Yes, the ride is stiffer, but when I'm dragging the 10K of weight in the trailer, it's worth it.



by:

I found this items cheaper on another site but etrailer match and then beat the price.
Item installed super easy, more work jacking up the truck and taking the tires off. Can be installed with out removing tires just make it easier to get it in. The item did lift the back of my truck 1 inch. See Pics.



by:

I Have had this suspension on multiple trucks and i love it . It takes the sway out of the truck when entering a exit ramp and taking sharp turns with a trailer or without, also reduces wheel hop and increases payload in the bed of the truck.I would recommend for all trucks pulling trailers.



by:

Easy install 2011 Tacoma crewcab long bed. Helped with sag when towing microlite travel trailer. Keeps the rear end raised in the rear a little when unloaded, but I like that look. Only complaint and its nothing big when truck is unhooked and empty when i get out I can hear alittle noise from RAS. Sort of like a bedspring coil. Night pic is with RAS installed daylight pic is with out installed



by:

I love the product since i have a 2021 toyota tacoma crew cab long bed with a campertop a robber mat and a jack thats around 450 pounds that a have at all times my truck was sittind low a lilbit plus it was swagging on the road i have summo spring to help my suspention but it was not enoght so i did my research but this was my better option i just installed it yerterday july-8-2021 and went for a ride where i ussually drive everyday and WOW now my truck rides very smood plus it lift my tryck 1 inch on the back now my tryck seats level it took me about 2 hrs but i did right i just follow the intructions and done i love the product the only thing that im concern is that the left side underneat the springleaft there is a breik line that is too close to the roadmaster suspention i hope that with the time dont hit that line because if it does thats the line for the breiks and i will be in trouble replacing it other wise evreything works great i recomend it 100% thanks guys i will buy it again?????best $500 that i spend on my truck



by:

I have a 2020 Silverado 1500 6 cyl Duramax with the Diesel Off Road package (3.73 diff). Travel trailer loaded is probably about 6,000 lb. I took several measurements during and after the spring kit installation. All measurements increased about an inch including the stock suspension with trailer and equalizer bars and with the spring kit installed at 1 mm spacing. A one inch improvement overall. I took the truck on a short drive and didn't notice any difference in ride (wasn't stiffer) which is what I wanted. Good to know that I can adjust the springs to the 2 mm spacing if I want to increase the suspension assist. Going camping next week and looking forward to see how it improves handling and porpoising.



by:

The bed of the truck measured 37.5" with a tool box weighing 200 lbs. The truck felt weighed down with passengers weighing 600lbs. Total weight 800lbs with a tank full of gas. After the install the truck rides smoother and certainly " like new". The stopping distance and acceleration distance have shortened drastically. I'm planning on loading up the bed and the Roadmaster Active Suspension RAS4611. My wife even drive it and she could feel the difference. "It drives like a muscle car." Buy it. Install time at a reputable mechanic shop was a 30 min. Install. I received them today at 1 pm and got it installed at 3:00 pm and finished the install at 3:30pm. It's an investment worth the price over traditional air bag system. Mechanic installed this on 2011 Nissan Titan SV.



by:

I have put these on every pickup that I have owned and not only does it assist with heavy loads, my tires have gone past 80,000 miles before needing replacement. All Chevy Duramax 2500's and 3500's!!



by:

Did not fit my 1995 F-150. ETrailer was very helpful in an effort to make any adjustments needed. We all decided that they were a "no go" for installation. Return was made easy. I have bought several other pieces of gear since. Thank Etrailer.



by:

i installed these on my 2001 ford f-250 4x4 and this is a huge upgrade whether your towing or empty.truck rides and handles better than it ever has. easy straight forward installation. you will need a t-55 for the front bolt and a 12mm ratchet wrench for the adjustable bolt that tightens the spring and a couple of 22mm and a 19mm wrench or crescent wrenches for the jam nuts. i took the weight off of the leaf springs for easy adjustment of the coil spring and used the thinner of the two disc that came with the kit and it raised the rear of the truck up exactly 1 inch empty without a trailer connected. if you use the thicker disc it will raise it more.



by:

I haven't hooked up my camper yet but set the springs up with the white wafer and it raised my truck 1 1/2 inches which is the amount it dropped after I put on a fiberglass topper. The ride is just a bit stiffer but a lot less body roll I noticed. Not impressed with the 25 Silverado suspension compared to my previous 2017 truck. If the squat is still there after I hook up the camper, there is plenty of adjustment left.



by:

Great product, helps with sway and when the truck has additional weight it progressively compensates. I would add this to any vehicle with leaf springs.



by:

Helps immensely, 12x6 inclosed trailer from NY to Florida and back up to NJ no problems



by:

Easy install when I rotated tires. Forgot to measure height difference, but it did raise a bit. I like the adjustability and not having to remove springs and shackles to add a leaf. Will be towing the camper with improved support.



by:

I don’t think they are really made for the old PU. 1997 k1500 8 ft bed with a 750 lbs camper tong weight I think I had to put to much pressure on the Kurt stabilizer chains to get level. It looked like the newer truck reviews on YouTube were great thanks Dingler.



by:

2023 F150. Install was fairly easy. Set at 25%. Ride unloaded a bit stiffer, but handling much better. Lifted rear of truck about an inch. Towing 7500 lb camper down NYS thruway which is crowded with much unforgiving bumps and pot holes the ride was more manageable. The 25+ mph cross winds did make for quite a bit of sway still, not as bad as before adding the RAS. Still felt passing trucks trying to suck me in, not as bad as before.
I plan on cranking the RAS to 40% on next camping trip and hopefully give the RAS 5 stars.



by:

I’ve bought a lot of products from etrailer and as always everyone I dealt with is professional and knowledgeable of the numerous products they sale. I used every resource they offer to help me decide what type of suspension upgrade I was going to use to improve the haul and tow ability of my 2017 diesel chevy Colorado 4x4 crew cab short bed. I chose the RAS system from Roadmaster. I also called them and ask some very detailed questions about using my OEM shackle instead of replacing with the plates in the kit and was told that was fine and that others had also. I got professional and knowledgeable info that helped make my decision. The product is exactly as promoted and every review out there on the internet about how good or unchanged the unloaded ride is after installing are true. My truck rides better now and it was already quieter and almost as smooth as my wife’s Cadillac. If your looking to improve the drive, tow and haul ability of your leaf spring vehicle, and I say vehicle instead of truck because I don’t know if they have them for other leaf spring vehicles, you are not going to find a better easier to install product that does that for your loaded or unloaded vehicle, IMHO. I will update in a year after next spring mulch haul. I don’t expect zero squat but hope to reduce and improve loaded steering performance. Took longer to jack up truck and remove tires than install kit.



by:

I purchased the RAS system 6 months ago to help with rear end sag & control while towing our 22 ft 4200lb camping trailer. It improved sag & helped handling even when not towing! I don't get the bounce when driving on bumpy uneven roads the wheels stay planted on the road. I recently purchased a 8000lb camping trailer & my 24 1500 Silverado handles it very well, I will adjust the RAS to the next step up for the extra weight when time permits.
The install took just over an hour with help from a friend & a car lift which is good since I'm 70 years old.
Great product!



by:

Just perfect to level the rear of my GMC 1500 Denali with the 29' Airstream (900 lb tongue wt). Preload is set at 1mm. I tried 2mm and it was overkill for this application. I was pleased with how easy the install was. I had to use a two jack hack to get the rear tires off since my 19" lift floor jack didn't quite have enough reach. You lower the differential after the tires are off so the rear axle is hanging free for the install. See photos



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by:

Balances ability to tow my 1800 squaredrop Hiker camper with 350 tongue weight as well as roof top tent on Leer 180 camper topper. Better handles load and side to side tipping on '21 Ranger. Keeps sage to a minimum.


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See what our Experts say about this RAS Vehicle Suspension

  • Will the RoadActive Suspension Custom Leaf Spring Enhancement Kit Fit My 2024 Ford Ranger Raptor?
    Hello Devon, Yes, the RoadActive Suspension Custom Leaf Spring Enhancement Kit # RAS29VR will fit your 2024 Ford Ranger Raptor. I see that there are air bag kits available for the 2024 Ford Ranger, but unfortunately none of them fit the Raptor model. We do have the Timbren Rear Suspension Enhancement System # TFRRGR. Timbrens are great if you’re carrying a constant load, but when you’re unloaded they can create a rougher ride, especially when you hit bumps in the road. Adding the #...
    view full answer...

Info for this part was:

Employee Daron K
Edited by:
Daron K
Employee Alex H
Written by:
Alex H
Employee Andy C
Installed by:
Andy C

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