bing tracking image
  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
RAS

RoadActive Suspension Custom Leaf Spring Enhancement Kit

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

Will this fit?

To see if this custom-fit item will work for you please tell us what vehicle you'll use it with.

zoom in icon
slider vertical icon
zoom out icon
Comment field cannot be left empty.
Name field cannot be left empty.

Thank you! Your comment has been submitted successfully. You should be able to view your question/comment here within a few days.

Error submitting comment. Please try again momentarily.

Product Images

Customer Photos

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.
  • All Info
  • Reviews (508)
  • Q & A (0)
  • Photos

RAS Vehicle Suspension - RAS4514-SAT

  • Leaf Springs and Helper Springs
  • Towing/Load Leveling
  • RAS
  • Rear Axle Suspension Enhancement
  • Standard Duty
  • Suspension Only
  • Helper Springs

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:

Ratings & Reviews

4.7

507 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:



by:



by:



by:



by:



by:



by:



by:



by:



by:



by:



by:



by:



by:



by:



by:



by:



by:



by:



by:



by:



by:



by:



by:



by:


25
507
Show More Reviews

See what our Experts say about this RAS Vehicle Suspension

  • Roadactive Suspension Kit that Fits 2024 Toyota Tacoma
    Hey John, I checked with Roadactive (formerly Roadmaster) and they do have a kit that fits your 2024 Toyota Tacoma with the part # RAS4514-SAT but it seems like it doesn't fit the 24 models actually as the truck has coil suspension so instead the Timbren kit part # T67KR would be a great option.
    view full answer...
  • Suspension Enhancements for a 2017 Toyota Tacoma with Firestone Airbags
    I do have a suspension enhancement option for your 2017 Toyota Tacoma that is compatible with the Firestone Ride-Rite Air Helper Springs part # F2407, however, the Timbren Rear Suspension Enhancement System part # TTORTUN4L and the Roadmaster Active Suspension Kit part # RAS4514-SAT will not work. In order to use a set of suspension enhancements with your currently installed Firestone Ride-Rite Air Helper Springs, I recommend the TorkLift StableLoad Rear Suspension Upgrade part # TLA7311...
    view full answer...
  • Does Roadactive Suspension Kit for 2022 Toyota Tacoma TRD Create Lift
    Hey Billy, so the Roadactive kit part # RAS4514-SAT that fits your 2022 Toyota Tacoma TRD was not designed to be a lift kit but it is adjustable in the amount of support it can provide so if you cranked it down hard enough you could get additional lift I am sure but I can't say if it would be exactly 2 inches.
    view full answer...
  • What is Best Suspension Enhancement Kit for 2006 Toyota Tacoma RWD
    Hey Billy, thanks for all of the details on your 2006 Toyota Tacoma! The best suspension enhancement kit would then be the part # RAS4514-SAT. This gives you the adjustable support you are looking for that also improves the handling and stability when loaded and unloaded unlike basically all other options available. It's all around the best option.
    view full answer...
  • Will Roadactive Suspension Kit RAS4514-SAT Fit 2023 Toyota Tacoma TRD Off Road
    Hey Jeremy, the Roadactive Suspension kit part # RAS4514-SAT is a fit for your 2023 Toyota Tacoma TRD and would work great for you. This will help reduce suspension sag like you are wanting and will do a great job improving handling and stability with your camper. Your 2023 Toyota Tacoma TRD off road does not have rear coil suspension and does have leaf springs like what this kit is designed to fit.
    view full answer...
  • Suspension Enhancement Recommendation for 2014 Toyota Tacoma
    Hey William, I would recommend the RoadActive Suspension system part # RAS4514-SAT for your 2014 Toyota Tacoma. This is by far the best suspension enhancement kit that provides all the support you are wanting without any real downside. Unlike other options this won't negatively affect your ride quality when unloaded and actually improves it as well as improves handling. What kind of trailer do you have?
    view full answer...
  • Will RoadActive Suspension Enhancement Kit Fit a 2018 Toyota Tacoma
    Sorry to hear about your dissatisfaction with the Timbren # TTORTUN4 on your 2018 Toyota Tacoma. They are hollow rubber springs and can create a bumpy ride when you have a load on the truck and go over speed bumps. As for the RoadActive Suspension Custom Leaf Spring Enhancement Kit # RAS4514-SAT, which is the right kit for your '18 Tacoma 4WD with the axle below the leaf springs, your ride will not be as stiff as with the Timbrens. The RoadActive Suspension is really a full system which...
    view full answer...
    Image 1 for
  • Recommended RAS Kit for a 2023 Toyota Tacoma TRD 4WD
    To determine which RAS kit you will need you're going to want to look underneath your Tacoma's rear axle. Some of the 2023 models have the leaf springs mounted below the axle. I have listed options for both below. The systems have identical 2,000 lbs capacities which means they will add an additional 2,000 lbs of support to your rear springs. Axle Below the Leaf Spring - RoadActive Suspension Custom Leaf Spring Enhancement Kit item # RAS4514-SAT Axle Above the Leaf Spring - RoadActive...
    view full answer...
  • Will RoadActive Suspension For 2019 Toyota Tacoma Give Smoother Ride Than Timbrens
    That's a good question, and the answer is pretty straightforward - yes, the RoadActive Suspension (RAS) is going to give you a smoother, less bumpy ride than the Timbrens for your 2019 Toyota Tacoma. Like you mentioned, the Timbrens do their job well due to the stiffness of their rubber springs, but that stiffness can also cause the ride to be uncomfortable or even jarring as there isn't much give to them. The RAS will absolutely remedy that while providing the same - or better - enhancement...
    view full answer...
  • Would RoadActive System part # RAS4514-SAT Fit 2017 Toyota Tacoma with 2 inch Lift
    Suspension enhancement like the RoadActive System part # RAS4514-SAT are not designed to improve unloaded ride quality in a vehicle. At best they leave the ride quality the exact same when unloaded but give more support to the suspension when loaded. This kit can be used on a lifted truck too. To improve overall ride quality you would need to look into a different set of shocks for the truck.
    view full answer...
  • Do You Carry The Roadmaster Active Suspension Kit 4614-SAT for a 2019 Toyota Tacoma?
    The RoadActive Suspension Custom Leaf Spring Enhancement Kit # RAS4514-SAT is the current part number 4614-SAT for your 2019 Toyota Tacoma 4wd. As the 4614-SAT was a rolling change replacement for the 4514-SAT from RAS we kept the parts under our same item number.
    view full answer...
  • RoadActive Suspension Custom Leaf Spring Enhancement Kit
    Yes it is possible to install both the RoadActive Active Suspension Kit # RAS4514-SAT with the Firestone Ride Rite kit you have installed on your 2016 Toyota Tacoma. The two kits would not interfere at all.
    view full answer...
  • Does The RAS Suspension System Affect Ride Quality Of A Tacoma When Not Towing
    The RAS Suspension Systems essentially preload your leaf springs making them stiffer to prevent sag. This will affect your unloaded ride quality but not as negatively as some other compatible suspension enhancements for your Tacoma. These systems are super easy to adjust tension on so you could always lower the tension when unloaded if you weren't happy with the ride quality and then add more tension when it's time to haul. If you have a 2WD Tacoma then you'll want the RoadActive Suspension...
    view full answer...
  • RoadActive Suspension Kit for a 2019 Toyota Tacoma 4 Door Long Bed 4WD
    Yes, it does make a difference and you will need to take a look at your leaf springs before you make your order to see which kit you will need. Both RoadActive Suspension kits item # RAS4514-SAT and item # RAS4524-SAT fit a 2019 Toyota Tacoma 4-Door Long Bed 4WD pickup but you have to look at your rear suspension first to determine if your leaf springs are above or below the axle. If your leaf springs are below the axle you will need the item # RAS4514-SAT and if they are above the axle...
    view full answer...
  • Can RoadActive Suspension Install on Lifted Toyota Tacoma
    Yep, you can install the RoadActive Suspension Custom Leaf Spring Enhancement Kit # RAS4514-SAT on your lifted Toyota Tacoma. There will not be any issue with the fit, and you made a really nice choice with the # RAS4514-SAT. These will help negate sag, improve your Tacoma's handling, and also requires no maintenance whatsoever, which is really nice.
    view full answer...
  • Best Suspension Enhancement for 2016 Toyota Tacoma TRD Sport to Improve Handling and Stability
    The suspension enhancement we offer for your 2016 Toyota Tacoma TRD 4WD that will do the best job at reducing sway, body roll, and improve handling would be the RAS system part # RAS4524-SAT for if you axle is located above the leaf spring or part # RAS4514-SAT if yours is located below it. With just this alone you'll see a dramatic improvement in all of the things mentioned. We would not recommend running this with any other suspension enhancement.
    view full answer...
  • How to Correct Vehicle Sag & Trailer Sway in 2014 Toyota Tacoma Prerunner Towing 4K Camping Trailer
    To both correct vehicle rear-end sag and also control or prevent trailer sway the best solution is a properly-rated weight distribution system, one that includes built-in sway prevention. These setups can do both of these things at once, both leveling of the tow vehicle and prevention of sway in the trailer. You can refer to the linked article and video for more information. The way to choose the right one is to know your fully-loaded road-ready trailer's tongue weight (TW), with water...
    view full answer...
  • Recommended Suspension Add-On for 2020 Toyota Tacoma Towing with Weight Distribution
    I recommend going with the RoadActive Suspension Custom Leaf Spring Enhancement Kit, part # RAS4524-SAT for axle above leaf springs or part # RAS4514-SAT for axle below leaf springs. This system is going to engage automatically so there is no takeup like with upgraded jounce springs. They can also be adjusted to better suit your exact needs unlike upgraded jounce springs. In comparison to air bags, these will require maintenance whereas the RAS will not. They only offer the sleeve type...
    view full answer...
  • Will The RoadActive Suspension Custom Leaf Spring Enhancement Kit Interfere With Brake Lines
    The RoadActive Suspension Custom Leaf Spring Enhancement Kit # RAS4514-SAT sits on top of the leaf springs and would not interfere with your brake lines.
    view full answer...
  • Solution for Suspension Enhancement on 2011 Toyota Tacoma X-Runner With Lowering Blocks
    In general, the Firestone # F2407 and other air bags are designed to fit vehicles at factory ride height. If you have a lift you can add spacers but when the vehicle is lowered like your 2011 Tacoma X-Runner they aren't going to work. Instead, I recommend using the RoadActive Suspension Custom Leaf Spring Enhancement Kit. The RAS system installs on your leaf springs so the lowered design of the X-Runner won't be a problem. These have a 2,000 lb capacity and turn your leaf springs into...
    view full answer...
  • Is There a RoadActive Suspension Kit that Fits 2022 Toyota Tacoma
    We do have a RoadActive Suspension kit that fits your 2022 Toyota Tacoma with the part # RAS4524-SAT for if you axle is located above the leaf spring pack or the # RAS4514-SAT for if your axle is located below the spring pack.
    view full answer...
  • What Is the Difference Between RoadActive Suspension Kits for 2016 Toyota Tacoma 4WD?
    The difference between the RoadActive Suspension Kit # RAS4514-SAT and the # RAS4524-SAT is more than price. The # RAS4514-SAT is intended for vehicles in which the axle is located below the leaf springs and the # RAS4524-SAT is intended for vehicles in which the axle is located above the leaf springs. They look almost identical uninstalled, but the installation and function is different.
    view full answer...
  • Which RAS Suspension Kit Fits 2020 Toyota Tacoma
    Both RAS kits part # RAS4514-SAT and # RAS4524-SAT fit the 2020 Toyota Tacoma but you have to run out and look at your rear suspension first to determine if your leaf springs are above or below the axle. If they are below you need the # RAS4514-SAT and if they are above you need # RAS4524-SAT.
    view full answer...
  • Will RoadActive Suspension Kit Fit 2008 Toyota Tacoma
    The RoadActive Suspension Kit, part # RAS4514-SAT, is designed to fit your 2008 Tacoma. This system helps eliminate botoming out of your suspension and helps reduce sway. I have attached a link to a product review video you can check out.
    view full answer...


< Previous
12



Do you have a question about this Vehicle Suspension?


Info for this part was:

Employee Jeff D
Installed by:
Jeff D
Employee Jameson C
Expert Research:
Jameson C
Employee Adam R
Expert Research:
Adam R
Employee Jeffrey L
Expert Research:
Jeffrey L
Employee Mary K
Written by:
Mary K
Employee Wilson B
Updated by:
Wilson B
Employee Noah M
Updated by:
Noah M
Employee Carrie F
Updated by:
Carrie F

At etrailer we provide the best information available about the products we sell. We take the quality of our information seriously so that you can get the right part the first time. Let us know if anything is missing or if you have any questions.


Product Experts Available Now!
Call 1-800-940-8924
<