RoadActive Suspension Custom Leaf Spring Enhancement Kit - Heavy Duty
Item # RAS3611-SLHD
Our Price: $589.00
Confirmed to Fit
2006 Ford F-350 Super Duty
4 Wheel Drive Models
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2006 Ford F-350 Super Duty - RoadActive Suspension Custom Leaf Spring Enhancement Kit - Heavy Duty
- Leaf Springs
- Rear Axle Suspension Enhancement
- RAS
- Heavy Duty
3,000-lb Capacity. Convert your Ford F-350 Super Duty'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:
- 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
Specs:
- 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.
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
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
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
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
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
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
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 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
3611SL-HD
Installation Details
Customer Satisfaction Score:
89% were satisfied with this product
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Customer Reviews
RoadActive Suspension Custom Leaf Spring Enhancement Kit - Heavy Duty - RAS3611-SLHD
Average Customer Rating: 4.7 out of 5 stars (741 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.by: Shane02/15/2023
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.
by: Robert 03/13/2024
2021 Ford F-250 Super Duty
So far I like the product it comes with good instructions and easy to install . Also the ride of the truck is better than the airbags I had a lot smoother and not so bouncy .
by: Gerald 08/26/2023
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.
by: Steven05/03/2023
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.
by: Michael11/16/2021
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
by: Stacy 05/05/2023
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.
by: Doug D06/07/2019
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.
by: Kyle05/07/2023
Pretty bouncy, not as good as other opt ions.
by: David 04/25/2021
2016 Ford F-250 Super Duty
Great improvement. Much more stable and level towing my 8000 pound travel trailer with my 2016 F250.
by: JohnW10/17/2019
Installing was not difficult, not as much sag when connected to 1080lb tongue weight trailer
by: David 10/05/2022
2014 Ford F-250 Super Duty
Made a huge difference in the way my truck sits with a 12,000 lb. RV on it
by: Alex 07/15/2021
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.
by: Alex 08/25/2022
Outstanding quality fast delivery.
by: Toby 01/31/2022
2019 Ford F-250 Super Duty
Easy install and really reduced squat!
by: Richard 09/23/2023
by: Clint 03/23/2023
2017 Ford F-250 Super Duty
by: Russell09/17/2022
2019 Ford F-350 Super Duty
by: Wendy 09/05/2022
by: Wyer04/04/2024
by: Javier 01/04/2023
by: Nick 04/15/2021
2016 Ford F-250 Super Duty
by: Eric 10/05/2022
by: Russell09/01/2022
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: Keith08/26/2022
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!
by: Michael06/21/2022
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.
25
740
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See what our Experts say about this RAS Vehicle Suspension
- Recommended Anti-Sway Bars And Suspension Enhancement For A 2022 Ford F-350 Hey John, Since body lifts only move the body away from the frame and don't change the distance between the frame and suspension the lift should be irrelevant to fitment in your case. For anti-sway bars I recommend the Roadmaster Front Anti-Sway Bar # RM-1139-180 and Rear # RM93VR. For the # RM93VR to fit you'll need the forward leaf spring bump pads, on either side, to be bolted to the frame and not riveted. For DRW models you'll want the # RM-1139-193 instead of the # RM93VR. As for...
view full answer... - Suspension Enhancement Recommendation for 2018 Ford F-250 Towing Fifth WheelThe Roadactive Suspension kits (formerly Roadmaster) are the best suspension enhancement solutions. They give you all of the support you are wanting to get rid of the sag but do not make ride quality worse. Actually they make the ride quality better, improve handling, while reducing sag. If you have factory overload springs you'd want the part # RAS3611-SLHD or if you don't have them you'd want the part # RAS3611-SHD.
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- Best Suspension Enhancement for 2021 Ford F-350 with Truck Bed CamperFor your 2021 Ford F-350 you'd really only need one suspension enhancement kit installed on your truck. If you were to need the support of two you'd be most likely overloading the truck so your best option is to go with one setup that's as ideal as possible. Now the best option for suspension enhancement for your truck is the RoadActive Suspension kit part # RAS3611-SLHD for if you have factory overload springs or part # RAS3611-SHD for if you do not have the overload springs. The RAS...
view full answer... - Recommended Suspension Enhancement for a 2019 Ford F-250 4WDI have a couple of options to eliminate the sagging in your rear end that will also improve the handling of your 2019 Ford F-250 4WD. It is the RoadActive Suspension System. The reason this is the best for your F-250 is because it is an active system which works to continually reinforce your original leaf spring suspension. Which system you will need is determined by whether or not your F-250 has the factory overload spring. I have attached a picture below that will help you identify whether...
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- 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... - Will the RoadActive Suspension Custom Leaf Spring Kit Fit a 2022 Ford F-350 Platinum TremorYes, 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... - Recommended Suspension Enhancement For Occasional Towing For 2021 Ford F-350 SRWSuspension enhancement is a very good idea for your 2021 Ford F-350, even with just occasional towing, but especially for longer trips as your truck will be easier to handle with a more level ride. What I highly recommend for your F-350 is the RoadActive Suspension, with the correct option depending on if you have top overload springs or not: - WITH Top Overload Springs: RoadActive Suspension Custom Leaf Spring Enhancement Kit # RAS3611-SLHD - WITHOUT Top Overload Springs: RoadActive...
view full answer... - Suspension Enhancement for 2019 Ford F-350 Super Duty that Improves Ride QualityIf you thought the air bag kit made the ride quality too stiff and harsh then a Timbren kit would not be for you as it would make it much harsher. The best suspension enhancement kit we have for your truck for your needs is the RAS kit part # RAS3611-SLHD which gives you the support you want and based on our experiences improves the ride quality.
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... - Recommended RoadActive Suspension System for 2015 Ford F-250 with Overload SpringsI have a solution for you, but the RoadActive # RAS3611-SHD are not designed to work with the overload springs on your 2015 Ford F-250. Instead, you'll want to use the RoadActive Suspension Custom Leaf Spring Enhancement Kit - Heavy Duty # RAS3611-SLHD. I've linked a review video of these systems that I recommend having a look at.
view full answer... - 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... - RoadActive Suspension Custom Leaf Spring Enhancement Kit For 2021 Ford F-250 Without OverloadYou 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... - Spring Rate of RoadActive Suspension Custom Leaf Spring Enhancement KitAccording to RoadActive Suspension the spring rate for the standard kit # RAS3611-S is 2,400 lbs. For the heavy duty # RAS3611-SHD it is 3,600 lbs. The heavy duty # RAS3611-SLHD is the same but only designed to fit if you have factory top overload springs on your 2016 F-250. I did ask if that was the actual pounds per inch measurement since it seems rather high and they weren't entirely sure. I know this measurement correlates with the weight capacity of each so it is probably best to...
view full answer... - Suspension Enhancement Recommendation for 2022 Ford F-350 Towing TrailerBetween Timbrens like the part # TFRTT350J and the SumoSprings # SSR-127-54 that fit your 2022 Ford F-350 crew cab long bed I would recommend going with the SumoSprings as you get the support you are wanting without causing the ride quality to be overly harsh. Timbrens do give great support but they are notorious for being pretty harsh. For my best recommendation for your truck I would recommend the RoadActive Suspension kit part # RAS3611-SHD if your vehicle does not have factory overload...
view full answer... - Why Do Air Bag Suspension Enhancement Kits Not Fit FX4 Models of 2020 Ford F-350FX4 model Ford trucks have different suspension than the standard trucks. Typically it's a slightly taller lift and different shocks which is why the air bag kit fits exclude them. So for a somewhat similar suspension enhancement setup for your truck the RoadActive Suspension kit part # RAS3611-SLHD is a really solid choice. You get the adjustable suspension support you want that also acts similar to a sway bar upgrade so it's a really great route to go.
view full answer... - Will RoadActive Suspension Help With Sag on 2015 Ford F-250 Super Duty Towing 5th WheelAir 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... - Best Suspension Upgrade for 2022 Ford F-250 to Prevent Sagging and SwayThe best suspension upgrade you can make for your 2022 Ford F-250 that is towing a trailer will be with the Roadactive suspension kit part # RAS3611-SLHD as this will do a great job getting rid of the sag and does the best job at preventing sway and improving handling. Unlike other similar options this will improve ride quality when loaded and unloaded as well.
view full answer... - RoadActive Suspension Kit that Fits 2020 Ford F-250 with Overload SpringsFor versions of the 2020 Ford F-250 Super Duty with the factory overload springs we have the RoadActive Suspension kit part # RAS3611-SLHD as a confirmed fit. This fits your Tremor model.
view full answer... - Recommended Suspension Enhancement for 2011 Ford F-250So we can definitely give your 2011 Ford F-250 a boost to its suspension enhancement for a more stable ride with better control, but I should note that aftermarket enhancements are not designed to improve the comfort of your overall ride at all times. Where it shines is when you are towing, have a heavy load in the bed, or even when making sharper turns. So with that said, I do not recommend going with front axle enhancement because it won't provide your truck with any type of benefit,...
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- Best Suspension Enhancement for 2020 Ford F-350 Towing Fifth Wheel TrailerThe RAS systems are by far the best suspension enhancement option for a truck like your 2020 Ford F-350 towing a fifth wheel trailer. You get (adjustable) suspension support which greatly reduces sag, you get improved stability and reduced sway, but unlike other options that make the ride quality rougher these actually are known to improve the ride quality. So if your truck has factory overload springs you'd want the part # RAS3611-SLHD and if you don't have them # RAS3611-SHD.
view full answer... - Which is Better Air Bags or RoadActive Suspension Kit for 2018 Ford F-250The 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.
view full answer... - Can 2014 Ford F-250 With 2 Inch Rear Blocks Use SumoSpringsIn order to find if you can use SumoSprings like the SumoSprings Rebel Custom Helper Springs - 2 Piece - Rear Axle # SS96MR on your 2014 Ford F-250 you will need to measure. You will need to know the distance from the bottom of your frame to the axle. These springs are 6" tall, and ideally you only want 1/2" of space between them. Slightly more may work but you have to keep in mind that they will not engage until they make contact. If you find that these will not work for you, you may...
view full answer... - Does RoadActive Suspension Make Fit for 2016 Ford F-250 Diesel 4WD King RanchYes RoadActive Suspension does make a kit that fits your 2016 Ford F-250 diesel, 4 wheel drive, King Ranch with the # RAS3611-SLHD.
view full answer... - Can RoadActive Suspension and Anti-Sway Bar Both be Used on 2017 Ford F-250You can certainly add both of these to your 2017 Ford F-250. The RoadActive Suspension Custom Leaf Spring Enhancement Kit # RAS3611-SLHD and Roadmaster Rear Anti-Sway Bar # RM-1139-173 would work well together. The Sway bar is going to help minimize side-to-side movement and helps balance weight transfer. It is especially helpful for top heavy loads and keeping your vehicle in line. The RAS kit will support and strengthen your leaf springs for an improved ride quality. These will also...
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Info for this part was:
Expert Research:
Michael H
Expert Research:
Jameson C
Video Edited:
Chris R
Written by:
Mary K
Updated by:
Wilson B
Updated by:
Matthew E
Updated by:
Noah M
Test Fit:
Adam E
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