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  1. Vehicle Suspension
  2. RAS
  3. Leaf Springs
  4. Rear Axle Suspension Enhancement
  5. Standard Duty
RoadActive Suspension Custom Leaf Spring Enhancement Kit
RAS

RoadActive Suspension Custom Leaf Spring Enhancement Kit

Part Number: RAS4514-SAT
In Stock
$539.00
Vehicle Suspension

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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 RAS4514-SAT can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.
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RAS Vehicle Suspension - RAS4514-SAT

  • Leaf Springs
  • Rear Axle Suspension Enhancement
  • RAS
  • Standard Duty

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.


Features:

  • Custom kit converts your vehicle's factory leaf springs into a mechanically active suspension system
    • Actively strengthens leaf springs for improved ride quality with or without a load
  • All-in-one suspension system improves stability, handling, and control
    • Eliminates axle wrap, wheel hop, and bottoming out
    • Reduces dangerous sway and body roll while cornering
    • Keeps your ride level when towing or hauling a heavy load
    • Improves traction while breaking and accelerating
  • Variable-rated coil tension springs automatically adjust to your vehicle's load
    • Activate immediately to support the extra weight
    • Disengage when unloaded, allowing your leaf springs to perform as intended
  • Customizable coil springs can be adjusted during installation to accommodate your towing or hauling needs
    • Independently adjustable for side-to-side leveling of off-center loads
  • Helps extend the life of leaf springs, shock absorbers, shackles, and even tires
  • Durable, epoxy e-coated steel construction
    • Corrosion-resistant brackets on the ends of each unit have a salt spray rating of more than 800 hours
  • Easy, bolt-on installation - no drilling, cutting, or welding required
    • Unit secures under the leaf spring and around the factory U-bolts
    • Fully assembled kit and hardware are included
  • Maintenance-free - adjustments and monitoring aren't needed once installed
  • Made in the USA


Specs:

  • Weight capacity: 2,000 lbs
    • RoadActive Suspension will not increase your vehicle's weight-carrying capacity
  • 5-Year warranty
  • 30-Day money-back guarantee


All-In-One Suspension System

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


Diagram of RAS Installed

RoadActive Suspension (RAS) kits enhance those passive leaf springs by converting them into a mechanically active, all-in-one suspension system. RAS kits have variable-rated coil tension springs that automatically adjust to your heavy load. Other suspension systems only solve a few problems and usually at the expense of other improvements your factory leaf springs may need. RAS, on the other hand, is a unique kit that provides everything you want in a suspension system without any trade-offs. It eliminates bottoming out like air springs, reduces sway and body roll like sway bars, keeps your ride level like helper springs, and improves traction and braking control like traction bars. This improves your vehicle's stability, handling, and control while you are towing or hauling, as well as when your vehicle is unloaded. RAS also makes your overall driving and towing experience safer and more comfortable, which greatly lessens driver fatigue.


How RAS Works

Close-Up of RAS Tension Spring

Each RAS unit has a powerful variable-rated coil tension spring that converts your passive leaf spring into a mechanically-active system. Once your vehicle is loaded, the tension springs immediately activate to absorb and support the weight. This allows your leaf springs to maintain their bowed position and keeps them from flattening out or flipping over, which greatly hinders their ability to bear a heavy load. The tension springs are variable-rated, which means that the heavier your load is, the more assistance they provide to your leaf springs. Because of this design, RAS reacts instantaneously, whereas hydraulics, air springs, and other suspension systems take time to react. And unlike your factory leaf springs, RAS stops sway and sag before they even start to happen. Additionally, when your vehicle is unloaded, the tension springs disengage, allowing your leaf springs to perform as intended without hardening your ride. RAS won't hinder your leaf springs' movement, nor will it cause any friction between any of the brackets.


Eliminates Axle Wrap and Wheel Hop

RAS Eliminates Axle Wrap

When under a heavy load, leaf springs are especially susceptible to axle wrap, which can cause wheel hop. Wheel hop is when the tires lose their grip on the road, causing a jarring, up-and-down movement. Axle wrap occurs when the circular motion of the tires cause the leaf springs to twist or rotate. If the leaf springs twist far enough, wheel hop can occur. RAS stabilizes your leaf springs by absorbing the force of the load they're trying to support. This eliminates axle wrap and wheel hop, as well as prevents your vehicle from bottoming out. Because of this, less strain is put on your vehicle. And by reducing some of this wear and tear, RAS helps extend the life of your leaf springs, shock absorbers, shackles, and even tires.


Reduces Sway and Body Roll

RAS eliminates sway and body roll

When driving along a curve while towing or hauling a heavy load, the back end of your vehicle or trailer can start to shift with that weight. If your factory leaf springs have flattened or twisted under this load, they won't be able to prevent it from shifting. Because of this, your trailer will sway away from your vehicle. This makes driving challenging and dangerous, as it increases the risk of body roll, which is when your vehicle drastically leans to one side. This can often cause you to completely lose control of your vehicle. Body roll is especially prevalent with multi-passenger vans and vehicles towing long campers, trailers, or boats. RAS provides a much safer ride by reinforcing your factory leaf springs and stabilizing your load. This helps prevent sway from occurring and reduces the chance of body roll while cornering, turning, and swerving. RAS also lessens the rocking motion that happens during windy conditions or when a semi passes by on the road.


Levels Your Ride and Improves Traction

RAS Levels Your Ride

When your vehicle is overloaded, the bulk of the weight transfers to the rear axle. Your factory leaf springs then become overwhelmed by this weight, as they are not strong enough to support it. This causes the back end of your vehicle to sag and the front end to rise, which means that the front tires have lost some of the grip they need with the road. In addition to loss of traction, it can also cause poor headlight aim, unintentional swerving, and an extremely bumpy and uncomfortable ride. RAS bolsters your factory leaf springs and enables them to provide support for your load without compromising ride quality or comfort. This keeps your ride level from front to back whether you are hauling a load in the bed or towing a boat, trailer, or camper. RAS also ensures that your tires have the traction they require while braking and accelerating, which improves the overall driving experience.


Customizable Coil Tension Springs

Adjusting Spring With Spacer

RAS is also customizable. During installation, the coil tension springs can be adjusted to 2 different tension settings or anywhere in between for improved road handling and support. To do this, rotate the springs while keeping the threaded rod still. As you turn the spring, use one of the 2 included spacers as a gauge to measure the widening gaps between the coils. In order for the RAS units to work as intended, you must tension the coils to a minimum of 25 percent with the 1mm white spacer and no more than 40 percent with the 2mm spacer. The springs can also be independently adjusted to compensate for off-center loads such as a handicap lift.


Easy, Bolt-On Installation

RAS Once Installed

This custom-fit kit comes fully assembled and is easy to install. Each RAS unit simply bolts onto your factory leaf spring with the included hardware, and drilling, welding, and cutting aren't required. First, position the eye hook bracket so that it wraps around the top of the factory leaf spring eye. Then the axle bracket secures under the leaf spring and around the factory U-bolts on the other side of the leaf spring pack. Once the maintenance-free RAS units are fully installed, you won't need to monitor them as you would with air springs.


Corrosion-Resistant Steel Construction

RAS Construction Close-Up

RAS is extremely durable and corrosion-resistant. The units are constructed of high-grade alloy steel, and they have an epoxy e-coat on the coil springs to provide extreme corrosion resistance. The brackets on the ends of each unit resist the effects of water and other elements, and they have a salt spray rating of more than 800 hours.



4614-SAT RAS Custom Active Suspension System for OEM Leaf Springs - Rear Axle

Replaces RAS 4514-SAT



This Product Fits The Following Vehicles




Customer Satisfaction Score:


Customer Reviews

RoadActive Suspension Custom Leaf Spring Enhancement Kit - RAS4514-SAT

Average Customer Rating:  4.7 out of 5 stars   (769 Customer Reviews)

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 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

Miguel

7/10/2022

Its been working very well i loaded a couple of times and its awesome



by:
2011 Toyota Tacoma

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

Rich

3/10/2021

Still working great. Towed a Flaggstaff microlite 23LB Travel trailer prob between 5 and 5500 LB’s to Niagra Falls with no problems, truck sat level with trailer and 2 adults,2kids. Getting ready to make a 2,000 mile round trip to disney in florida in a few weeks.



by:
2018 Toyota Tacoma

Rarely adding an aftermarket "upgrade" to any of my vehicles am I 100% satisfied with the outcome. There is usually a trade off with something. However, this is one of those upgrades that has zero con's that I've discovered so far. I was struggling to keep the leaf springs on my modded out 3rd get Tacoma from "flattening" out because I always have at least 900 lbs of payload in my bed. Adding the RAS has prevented this from happening. I also thought that they would affect off road performance, since I've never seen them in an off road application before, they don't. People on the trail often ask "What the heck?" when they see them on my rig. I tell them that RAS is the easiest to install, most cost effective solution to manage sag without sacrificing ride quality. There is the famously noted "Taco lean" and it's most prominent after fueling up. RAS will help iron this out. I've had them on for about a year now and they haven't needed any adjustments. Kinda like (Ronco), "set and forget it". I don't know their duty cycle is but, I wouldn't hesitate buying them again!



by:
2019 Toyota Tacoma

Had the kit installed today at the local Toyota dealer on a 2019 Tacoma. The truck had a greatly improved ride and seemed to have a more steady rear end feel. I plan on towing an RV in a few weeks and to the mountains in July, and have a greater confidence in performance. It did raise the back a good 2", it doesn't look bad, as I had expected. I firmly believe that this was the right choice, I can't wait to put it to use!



by:

We can tell a big difference with the performance of the vehicle since we installed the roadactive suspension. The ride is smoother, there’s no more bounce when we’re towing our camper.



by:
Nissan Leaf

The leaf spring enhancement kit work jast as it was advertised. It eliminated the sag in the back of the truck when my camp trailer was hooked up and made pulling the trailer easier when traveling on rough roads.



by:
2011 Toyota Tacoma

2nd one and love it. 1st was for my Tacoma and now for my F150. Get this over sumo springs or airbags as you get a better ride with and without towing. Custom support is awesome at RAS. Tip - adjust the side with gas tank 25% more to balance for a perfectly level ride - that worked for me



by:

easy install does the job optional adjustment disc was missing but i have installed before and knew what i wanted

Duff

3/14/2023

as a repair shop we have installed this on several vehicles. Customers have been satisfied with the out come



by:
2013 Toyota Tacoma

Very happy with the Roadmaster active suspension kit. I had it on other trucks before this one, and was always pleased with how it worked, So never thought twice about using it on next truck. Performs well and does everything it is supposed to do. Much better than cheaper items, it will last and be on truck as long as truck last.



by:
Toyota Tacoma

My Tacoma came with tow package but manufacturer doesn’t have an electric brake controller. I didn’t like the look of the after market ones until I checked etrailer. They carry The Redarc that tucks the controller under the dash with a nice looking, back lit , dial that fits in the dash with a factory finished look. Install was plug and play. Adding Roadmaster Helper springs really help to stabilize the Tacoma when towing my camp trailer, or when carrying loads in the bed of the truck.
Thanks etrailer.



by:
2014 Toyota Tacoma

Prompt shipping, good price, happy. The Roadmaster was easy to install and works as advertised. Truck used to squat under weight. Now even with the riding mower in the back, I cant even tell its there. No squat and good handling. Unloaded there is no effect on ride. Cranked to max, raised the rear about an inch. Like them.



by:

Great product. It took me longer to round up my tools than it did to install. The video by etrailer was a great help. As always, great service from etrailer and their staff. They really do care about their customers. Have ordered my Blue Ox Sway Pro, hitch ball and tekonsha brake controller from them. You can't go wrong with etrailer.



by:
2021 Toyota Tacoma

Seems to work as advertised. I installed it on my 2021 Toyota Tacoma. The installation was simple and quick. It took me longer to get the truck jacked up and the tires removed than it did to install the product. My truck has a little less squat with a load and I don’t notice any stiffer ride when empty. I would definitely recommend.



by:

Works great, although I think it should be a little bit better as far as stiffness with a load on.



by:

Easy to install. The ride is great. I did use the third hole to open up more clearance with the brake line. That worked well.



by:
2013 Toyota Tacoma

Very easy install and so far happy with what I'm seeing it do for my Tacoma. Etrailer did a great job of letting me know when it shipped and would arrive. Great service as always.



by:
2017 Toyota Tacoma

Ricky

10/31/2022

RAS vehicle suspension is still working great after a rear. I have been pleased with its load carrying ability and no rear sag.



by:

Shipment was delayed by manufacturer but you guys kept me updated on status



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2022 Toyota Tacoma



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2019 Toyota Tacoma



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Used Items Available
Used Picture for RoadActive Suspension Custom Leaf Spring Enhancement Kit
Used Picture for RoadActive Suspension Custom Leaf Spring Enhancement Kit
Used Picture for RoadActive Suspension Custom Leaf Spring Enhancement Kit

Condition: Installed

Notes: Item has been previously test fitted and has minor cosmetic scratches and scrapes.

$409.05
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