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RoadActive Suspension Custom Leaf Spring Enhancement Kit - Heavy Duty

RoadActive Suspension Custom Leaf Spring Enhancement Kit - Heavy Duty

Item # RAS3611-SLHD
Our Price: $589.00
Vehicle Suspension

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Shipping Weight: 38 lbs
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3,000-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 - Heavy Duty part number RAS3611-SLHD can be ordered online at or call 1-800-940-8924 for expert service.
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RAS Vehicle Suspension - RAS3611-SLHD

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

3,000-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.


  • Heavy-duty 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


  • Weight capacity: 3,000 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.

3611-SLHD RAS Custom HD Active Suspension System for OEM Leaf Springs - Rear Axle


Installation Details RAS3611-SLHD Installation instructions

This Product Fits The Following Vehicles

Customer Satisfaction Score:

Customer Reviews

RoadActive Suspension Custom Leaf Spring Enhancement Kit - Heavy Duty - RAS3611-SLHD

Average Customer Rating:  4.7 out of 5 stars   (690 Customer Reviews)

3,000-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.


Really like this product. Was super easy to install and instructions were easy to read. Amy was very helpful in recommending the correct part and even took the order for me. Its winter here in the Rockies so I haven't had a chance to test out the load of my 5th wheel, but the ride still feels smooth. I have ordered from etrailer before and always have a good experience. Choose them with peace of mind.

2017 Nissan Leaf

This is the 2nd pair I purchased. My first was for a 2017 Ford F150 and the
first thig I did when I purchased my 2021 F250 Super Duty was to get a pair for that truck. I don't know that I will ever have a truck without a Leaf Spring Enhancement Kit.


I use it with my Timbrens and it give the truck a great ride when not towing. It also seems to help the Timbrens with a relaxed reflex response to dips and bumps when towing. I'm very happy with it.

2020 Ford F-250 Super Duty

Well I just installed them today so I went ahead and loaded my excavator just to see how much the rear of my truck squatted and it didn’t squat near as much as before, I’m pulling 16000 lbs trailer and excavator with a 2020 F250 super duty and before I installed I normally would have to park my excavator in just the right spot to give me enough tongue weight that I needed but I always had that seat of the pants feeling that I didn’t like while towing it, drove down the road with everything installed and loaded and it honestly felt like a completely different truck, didnt pull it but about 4 miles but so far so good, think I’ve finally found my solution


I really like these. I have a pair on both my trucks. They don't take away all the bouncing, but they take a whole lot of the bouncing away.


Pretty bouncy, not as good as other opt ions.

Ford F-150

Great product! It does what it advertises and is a breeze to install on my F-150 but a little harder on the 350 since you have to remove the overload spring. Works great helps keep truck perfectly level when towing my 10k lb trailer. Highly recommend.


Installing was not difficult, not as much sag when connected to 1080lb tongue weight trailer

2014 Ford F-250 Super Duty

Made a huge difference in the way my truck sits with a 12,000 lb. RV on it

2016 Ford F-250 Super Duty

Great improvement. Much more stable and level towing my 8000 pound travel trailer with my 2016 F250.


Outstanding quality fast delivery.

2021 Jayco Jay Flight SLX Travel Trailer

Install took about 30min. Seems my rear is a hair higher at 25%. Going to tow 7k about 650mi this weekend. See how much if helps.


2017 Ford F-250 Super Duty

2019 Ford F-250 Super Duty

Easy install and really reduced squat!

2019 Ford F-350 Super Duty




2016 Ford F-250 Super Duty


Admitedly, I haven't even rolled my '07 Silverado 2500HD classic out of the garage yet, but I'm already very pleased. I had to go to a neighbor for a 10mm hex key socket and was slowed down by my 7yo kid 'helping', but it was still only 90 minutes my jack stands were in use. Easiest thing to do!
My only small downsides so far:
* needed to find a 10mm hex key that I apparently don't own, not sure why they picked that fastener
* wish I put some loc-tite on; just to make me feel better
* distance to drop the axle so the suspension fully hangs was way further than I expected; barely had my jack stands tall enough to get the job done.

These aren't really bad on the product, just notes for future customers. We're towing the 5er about an hour an a half this coming week, hopefully it steadies up a lot!


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.


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.


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!


Installed this today on my 2023 Ford F150 Lariat 4x4 with the tow package. The kit arrived within 2 days of ordering. The box was slightly open but the springs appeared undamaged. I elected to do the install myself and opted to get a 4 ton floor jack to replace my very old 3 ton. I’m very glad I did. After blocking the front tires and setting the parking brake, I loosened the wheels and raised the rear at the differential using a small 2x4 block to span the contact points. I took the wheels off and originally set my jack stands in front of the leaf spring on the frame. Lowering the truck onto the stands was not effective. There wasn’t enough travel to provide relief to the springs. I ended up setting my jack stands on some 1x16 scrap pieces and put them under the spring attachment point. This gave me just enough room on my floor jack to unburden the springs. Once I got over this small hurdle the install went smoothly. This took about an hour to very carefully construct as I didn’t want to drop my brand new truck on the ground. Brand new 5 ton jack stands would have eased my mind considerably. My install includes a spacer for the bump stop to offset it towards the centerline of the vehicle. The instructions weren’t intuitive and it took a few minutes to figure out the bolts. You need to insert the provided bolt into the spacer and attach the spacer to the frame with the original bump stop bolt. It’s the only one you can get a socket on in the depression. The bump stop then attaches to the provided bolt you inserted into the spacer using the provided nut. You will need a deep well 15mm socket for this attachment. Fortunately I had one. I set the spring using the 25% white spacer, reinstalled the wheels and set the truck back on the deck. The truck now sits 3/4” higher in the rear. I drove around and noticed that I was sitting a little higher as the site picture changed a bit. The truck didn’t seem to ride differently empty. If anything it seemed a little more cushioned though no less responsive. I towed my 9000lb travel trailer previously with a Ram 2500 6.7l diesel that had Sumo springs and a WD hitch. I got tired of the cost and maintenance and selected this Ford because it could haul the trailer. I chose the RAS over the Sumo springs because of how much squat I observed when I hooked up the trailer initially. I will update after I tow the trailer. My only concern at the moment is that the bump stop spacer isn’t going to provide enough clearance from the bracket.

Show More Reviews

See what our Experts say about this RAS Vehicle Suspension

  • What Suspension do You Recommend for My 2022 Ford F-350 Super Duty when Towing a Fifth-Wheel?
    For a great suspension enhancement for hauling your fifth-wheel trailer on your 2022 Ford F-350 Super Duty, I recommend the RoadActive Enhancement Kit # RAS3611-SLHD. This kit will fit 2-wheel and 4-wheel drive models as well as single rear-wheel and dually models. Apart from the kit's 3,000 pound capacity, the leaf spring enhancements greatly extend the life of your factory springs. This is super important to consider if you plan to haul your fifth-wheel trailer often. Also, the leaf spring...
    view full answer...
  • Best Rear Suspension Enhancement for 2022 Ford F-350 Towing Trailer
    For your 2022 Ford F-350 the best rear suspension enhancement we have is the RoadActive Suspension kit part # RAS3611-SLHD by far. This is only option that is easy to install, provides adjustable support, is basically maintenance-free, improves loaded an unloaded ride quality, and also improves stability. Other options will provide additional support but will affect ride quality by making it harsher, install is more difficult, and require maintenance like monitoring air pressure.
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  • Does Overload Spring on 2019 Ford F-350 Need to be Removed to Install RoadActive Suspension
    To answer your first question, yes the top overload spring on your 2019 Ford F-350 dually does need to be removed in order for you to install the RoadActive Suspension Custom Leaf Spring Enhancement Kit # RAS3611-SLHD, as you can see by the cut out of the instructions I have added. In regards to raising the rear of your truck when it is unloaded, the RAS kit will not raise it at all, no. One of the great things about this enhancement is that it is an "active" system which essentially...
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  • Will the RoadActive Suspension Custom Leaf Spring Kit Fit a 2022 Ford F-350 Platinum Tremor
    Yes, the RoadActive Suspension Custom Leaf Spring Enhancement Kit # RAS3611-SLHD will work with both the 2022 Ford F-350 Platinum with Tremor package and the 2022 Ford F-350 Platinum without the Tremor Package.
    view full answer...
  • RoadActive Suspension Enhancement for 2002 Ford F-350 with Factory Overload Springs
    I spoke with my contact over at RoadActive Suspension and there is a kit for your 2002 Ford F-350 with factory overload springs. It is # RAS3611-SLHD. But you will have to remove the factory overload springs to install it. The system though will more than make up for any capacity lost and you will also get all of the other benefits of the system including stability and better ride quality. This item also comes with spacer plates to take up the gap from the factory overload springs.
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  • Does Installing RAS Leaf Spring Enhancement RAS3611-SLHD On 2020 Ford F-350 Affect Ride Quality?
    The RoadActive Suspension Custom Leaf Spring Enhancement Kit - Heavy Duty # RAS3611-SLHD you were looking at is designed for trucks with the upper overload spring and will include everything needed to remove it on your 2020 Ford F-350. The # RAS3611-SLHD will basically act as a better overload spring meaning it will not ruin your unloaded ride, and will actually improve traction, reduce sway and body roll, and eliminate axle wrap so you will have a much more enjoyable loaded and unloaded...
    view full answer...
  • Which is Better Air Bags or RoadActive Suspension Kit for 2018 Ford F-250
    The RoadActiveSuspension kits like the # RAS3611-SLHD that fits your 2018 Ford F-250 provide the best balance of support, ride quality, and stability. Air bags do a great job reducing sag but they ride quality ends up harsher and you don't get the benefit of additional stability either. I attached an install video for this for you to check out as well.
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  • Suspension Enhancement Recommendation for 2022 Ford F-350
    For your 2022 Ford F-350 the best suspension enhancement is the RoadActive Suspension Kit part # RAS3611-SLHD which will do a great job getting rid of suspension sag, is easily adjustable, easy to install, improves ride quality and stability. Most kits are known to make the ride quality rougher but the RAS improves it which is why it's the best option. This also fits with dually models too.
    view full answer...
  • How Does Weight Capacity of RoadActive Suspension Kit Affect Towing Capacity
    The capacity of the suspension enhancement kits we offer for vehicles like your 2017 Ford F-350 is basically how much additional support they can provide to help out the factory suspension of the truck. So the # RAS3611-SLHD can provide up to 3,000 lbs of additional support which will allow your factory suspension to carry the weight easier. This does not increase the capacities of the vehicle though as it basically just gives additional support to carry the current capacity in a safer way.
    view full answer...
  • Will RoadActive Suspension Enhancement fit 2020 Ford F-250 FX4 Lariat With Firestone Air Bags
    The answer to both of your questions is yes. As long as you do not have factory top overload springs the RAS # RAS3611-SLHD can be used with your Firestone air bags. These will add additional support to your 2020 Ford F-250 and compliment the air bags. The two combined will definitely reduce the sag you're still experiencing. These will also help to increase the life of your leaf springs and other suspension components as an added bonus. The RAS system disengages when unloaded, so even...
    view full answer...
  • Correct RoadActive Suspension RAS for 2016 Ford F-250 with Factory Overload
    The correct RoadActive Suspension Custom Leaf Spring Enhancement Kit for a 2016 Ford F-250 with factory overload leaf springs is part # RAS3611-SLHD. These are designed to be used with factory leaf springs including the overload. They will do a great job of reducing sag therefore improving ride quality and control. They however will not increase towing capacity which is the case for any enhancement kit.
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  • Will RoadActive Suspension Help With Sag on 2015 Ford F-250 Super Duty Towing 5th Wheel
    Air bags can be tedious so going with a kit you don't have to maintain on your 2015 Ford F-250 Super Duty is smart, and the best option to both help with the sag and sway you are experiencing is the RoadActive Suspension system. The correct fit for your truck is the following part number: - RoadActive Suspension Custom Leaf Spring Enhancement Kit - Heavy Duty # RAS3611-SLHD The heavy duty # RAS3611-SLHD is what you'll want for towing a 5th wheel due to the amount of pin weight in the...
    view full answer...
  • Does RAS Leaf Spring Enhancement RAS3611-SHD Fit A 2021 Ford F-250 4WD?
    The RoadActive Suspension Leaf Spring Enhancement Kit # RAS3611-SHD you mentioned will fit your new 2021 Ford F-250 Super Duty 4WD as long as it does NOT have the top overload springs. If it does have the top over load springs you would need the # RAS3611-SLHD instead. I included videos of the products mentioned for you to take a look at.
    view full answer...
  • RoadActive Suspension System for 2012 Ford F-250/F-350 with Factory Overload Springs
    If your 2012 Ford Super Duty has an overload spring ABOVE the leaf spring pack then you would need to use # RAS3611-SLHD. Then, to use the RoadActive suspension system # RAS3611-SLHD, the top overload spring will have to be permanently removed.
    view full answer...
  • Comparing RAS3611-SHD and RAS3611-SLHD For 2011 Ford F-250/350
    The difference in the RAS kits for your 2011 Ford F-250/350 is the RoadActive Suspension Custom Leaf Spring Enhancement Kit - Heavy Duty # RAS3611-SLHD fits trucks with the top overload springs and can fit dual rear wheel models, where the # RAS3611-SHD does not work with the top overload springs or dual rear wheels. So if your truck has the top overload springs or has dual rear wheels you will need to go with the # RAS3611-SLHD, and if your does not have top overload springs or dual rear...
    view full answer...
  • Difference Between RoadActive Suspension HD Kits For 2011 Ford F-250
    Good question; I reached out to RoadActive regarding the difference between the two kits for your 2011 Ford F-250, and there is indeed a difference. The part intended for trucks with an overload spring includes spacers needed for the installation after removal of the overload spring. So here is what you'll need, depending on if you have the overload spring or not: - WITHOUT Overload Spring: RoadActive Suspension Custom Leaf Spring Enhancement Kit - Heavy Duty # RAS3611-SHD - WITH Overload...
    view full answer...
  • RoadActive Suspension Enhancement Recommendation for 2016 Ford F-350 for Towing Camper
    For fifth wheel towing it really is going to depend on the weight of your trailer whether you would want the standard duty RoadActive Suspension Kit part # RAS3611-S or the HD version part # RAS3611-SLHD. One big factor to consider is whether or not you have a dually axle. If that's the case the only fit is the HD version I mentioned part # RAS3611-SLHD which most likely would be best fit since fifth wheel trailers can be pretty heavy. If you have a lighter trailer relative to the towing...
    view full answer...
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  • Does the RAS for a 2016 Ford F-250 Eliminate Wheel Hop and Axle Wrap?
    Yes, it does and they do a great job of it! Axle wrap occurs when the turning of the tires causes the axle housing to twist or rotate. This rotation forces your leaf springs to bend into an S-shape causing you to loose traction. The RoadActive Suspension Custom Leaf Spring Enhancement Kit item # RAS3611-SLHD holds your F-250's leaf springs in their original bowed shape. The S-shape twisting followed by wheel hop, is eliminated because the tires transfer torque to the ground more efficiently. I...
    view full answer...
  • RoadActive Suspension Custom Leaf Spring Enhancement Kit For 2021 Ford F-250 Without Overload
    You will want the RoadActive Suspension Custom Leaf Spring Enhancement Kit # RAS3611-SHD for your 2021 Ford F-250 since you do not have the overload spring. The RoadActive Suspension Custom Leaf Spring Enhancement Kit # RAS3611-SLHD is for models with a top overload spring on their leaf springs.
    view full answer...
  • What RoadActive Suspension Kit Do I Need For My 2022 Ford F-250 Cab And Chassis
    Yes The RoadActive Suspension kit # RAS3611-SHD will be a good fit for your 2022 Ford F-250 cab and chassis. Provided it does not have factory top overload springs. If it does have factory top overload springs you will want to go with # RAS3611-SLHD instead. These can be identified by looking at the top of your leaf springs and will basically look like another leaf that is not connected to the rest. I have attached a picture that should explain what they look like a bit better.
    view full answer...
    Image 1 for
  • How to Tell if 2015 Ford F-250 Has Overload Springs for Selecting RoadActive Suspension Kit
    Look at the rear leaf springs of your 2015 Ford F-250. You should see a bundle of metal springs held together with a metal band. If you see a spring on top of this that looks separate and angles up to make contact with a bracket on the frame that means you have the overload spring and would want part # RAS3611-SLHD. If not then you would need the part # RAS3611-HD instead.
    view full answer...
  • What Suspension Enhancement Do You Recommend for Hauling Heavy Loads on My 2021 Ford F-350?
    If you plan on towing heavy loads often on your 2021 Ford F-350, I recommend leaf spring enhancements like the RoadActive Suspension Custom Leaf Spring Enhancement Kit # RAS3611-SLHD (3,000 pound load rating) or # RAS3611-S (2,000 pound load rating). The reason why I recommend the RoadActive enhancements is because these will ultimately prolong the life of your factory springs. Also, you will be able to manually tension the springs for the desired firmness you need. In addition to these...
    view full answer...
  • What is Best Suspension Enhancement for 2022 Ford F-350 Towing Trailer
    The best suspension enhancement we have for your 2022 Ford F-350 is the RoadActive Suspension kit # RAS3611-SLHD for if you have the factory overload springs or # RAS3611-SHD for if you do not. Unlike other options you get the best of all worlds with the RAS kits. The support is adjustable, the install easy, the ride quality is improved loaded and unloaded, and handling is improved as well.
    view full answer...
  • How to Tell if 2019 Ford F-250 Has Overload Spring for Picking Out RoadActive Suspension
    For your 2019 Ford F-250 there are two RoadActive Suspension kits for your truck available. There's the part # RAS3611-SLHD which is intended for versions of the vehicle that do come with overload springs and there's the # RAS3611-S which does not. Go look at the rear springs on your truck, you should see a bundle of metal springs held together with a metal band. If you see a spring on top of this that looks separate and angles up to make contact with a bracket on the frame that means...
    view full answer...

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