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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.
Features:
Specs:
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.
Roadmaster Active 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.
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.
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.
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.
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.
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.
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.
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.
Installation Details 
2003 - 2008 Ford F-150
2004 - 2004 Ford F-150 Heritage Series
2006 - 2008 Lincoln Mark LT
1975 - 1991 Ford Van E-100
1975 - 2007 Ford Van E-150
1975 - 2007 Ford Van E-250
Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.
Today, we're going to take a look at the Roadmaster Active Suspension Kit, part number RAS3611. The Roadmaster Active Suspension Kit is going to help to convert our basic leaf spring kit into a mechanically active suspension. This is going to provide great assist for vehicles with the rear leaf springs without compromising any of their ride quality. It's going to help to eliminate any of the bottoming out or axle wrap that we can sometimes get, which is going to lead to great improvements and road handling. It helps to reduce the sway and the body roll that we often we get during cornering. The Roadmaster Active Suspension Kit works with or without a load. It's going to absorb and dissipate any load force that we might have when our vehicle is loaded, and whether it's loaded or unloaded, we're going to have improved vehicle stability, handling, traction, and control.
Now, when we receive our suspension kit, it's all going to be preassembled, really easy straight forward installation. We've got both sides here. We're going to have our instructions, our warranty registration, and even our spacers so we can fine tune the system. The thinner one, that's going to give us a 25% improvement. The thicker one, that's a 40% improvement. Now, the system itself is going to have a few main components.
We've got our eye-loop strap. We've got our main spring here in the center. This does all the work, and then, we've got our axle brackets here where they'll mount onto the truck. Like I said, really simple installation. We're only going to have to take care of getting one bolt to install it on the vehicle.
Then, we can make our adjustments on our spring. Now, our eyehook, our spring, and our brackets are full epoxy-coated. This is going to offer us up to $800 of salt spray protection. Even if we're using them up North or here in the Midwest, we're not going to have to deal with a whole lot of rust and corrosion. The threaded rod, all of our moving points here, and our bolts are going to have spacers that are fully treated as well, again to help prevent rust, and then, we're going to have some high-quality fasteners here to use as jam nuts to get it all locked into place once we've got it where we want it positionwise. Here on our eyehook, you can see we've got our articulating ball/socket setup. The same thing here on the other side, a rotating bar setup here.
This is going to allow both of our leaf springs full maneuverability, so we'll never have any of those binding situations to where it's kind of bound up or our spring gets caught, anything like that. The axle brackets themselves are fully adjustable to fit a wide variety of vehicles. You want to use whichever one most closely matches your setup. To start our install, we need to take the tires off each side of the vehicle. The way we want to set it up is we want the tires to be up off the ground but we want it to be supported or resting on jack stands. You can use those on each side of the axle and also in the middle on your center differential, they'll instruct you to use a jack. Just follow the instructions, they're going to tell you exactly how to get it set up so you can do the work. Then, we want to take the center caps, each wheel is going to be a little bit different. It might look just like this, it might have a center cover, or whatever, but remove both rear wheels once you got your truck properly set. For installation, we're going to grab the spring pack so that when our hook is oriented toward the back that our main bolt comes into the top part of the bracket. You see there Then, we want our hook to go right around our eye on the back of the spring there. We'll grab a couple of either 3/4" ratchets or 19mm and let's take our bolt out that's here on the end. It holds our spacer into place. Take that on out. Now, what we want to do is get one of our 5 holes so that we can have our bolt and spacer here behind the U-bolt block. To extend this length, what we need to do is hold on to the threaded rod while we turn our spring toward us. Then, we can bring our bolt back in and we go through the arm on our bracket, and of course we want to put our spacer on there. Then, we'll add on our nylon locking nut. You want to be careful if you've got any sensors or any wires or anything like that, that we don't have it pinched in behind there. Then, we're ready to tighten down our bolt. Now, we're not going to tighten our bracket down so much as to where it actually sandwiches our U-bolt here. What we're looking for is to tighten it down enough to capture our spacer so it won't move. That's going to be oriented right there just underneath our spring and all the way back against that block. Then, we'll take the slack out of the system by doing the opposite of what we did to extend it. Now, we want to take another look at our eyehook here. We want that to be centered on the spring pack. Then, we'll feel our spring actually get tight while we're turning it. Right there, it's starting to tension up a little bit. Now you see everything is locked into place and it won't be moving. Now, it's time to make our adjustment. While holding the nut that's located here at the end of our threaded rod, we'll need a 22mm ratchet. We can come to the other end with our 12mm and start tightening our spring. As we turn our small nut or bolt located here on the end, we'll start to see the gaps in our springs increasing. Periodically, we're going to want to take our disc and check. These discs, white as we said is a 25% increase, the black is a 40% increase, and they should barely pass through those rings. As you see right now, they're not and we need to keep going with it. Here you can see our spacer just barely passing through there, so we know we've got it set properly. If we're looking for extra performance out of the system, we can switch from the 1mm up to the 2mm, and we want to follow that same process. Now, we'll head over to the driver side and repeat that same exact process. Now, we'll get our tires put back on here and torqued down to specification, and then, we'll go ahead test out that system and see how it worked. Now that we've seen how it works, how it can help us, and how to install it, that's going to complete today's look at the Roadmaster Active Suspension Kit, part number RAS3611.
Average Customer Rating: 4.8 out of 5 stars (75 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.Review from a similar RAS RAS in Vehicle Suspension
Very easy to install and make a big difference towing a trailer! 717907
Review from a similar RAS RAS in Vehicle Suspension
I own a 2017 F150 and placed the RAS3611-y kit last year. So far the ride improvement and the handling when pulling my equipment trailer with 7000# load is great. Air load adjusters would have been a mistake. Thanks George J. for a great product. No need for load levelers with this kit. 675401
Review from a similar RAS RAS in Vehicle Suspension
product came very fast! all was packaged extremely well and no damage to any of the items I ordered. I have not installed them yet but I am excited to get them on and hopefully see that they take that little extra sag out of my truck while pulling my travel trailer! watched many video's on the installation process and seems to be very simple and straight forward... thanks etrailer 307783
Review from a similar RAS RAS in Vehicle Suspension
Product was very easy to install. Very well made. It took me about 35 minutes to install both sides once the truck was on Jack stands. Product did raise the rear of my truck a little. Can't say how much because I forgot to measure before I started. Truck still rides nice, no harshness or strange noises. I purchased the roadmaster active suspension to help eliminate squat and improve driveability while towing our 7500lb travel trailer. Hopefully I will get to try it out with the trailer soon. 595303
Aaron - 01/07/2020Review from a similar RAS RAS in Vehicle Suspension
I bought this based on I think the same product I bought several years ago for a 1997 Dodge Ram 1500. At that time, I bought a kit for for a Ram 2500 and was very impressed. I put a truck camper on the Dodge and I don’t think it settled an inch and when I drove it I hardly knew the camper was back there at all. No sway and no handling problems at all. This time I bought the kit for a Nissan Titan, pulling a 25’ travel trailer (about 7000#). The truck rear still settles and is not in a level attitude in transit without the weight distribution hitch. The suspension kit makes it better but not as much as I expected. 565780
Jim - 10/02/2019Review from a similar RAS RAS in Vehicle Suspension
The product was very easy to install, and was very happy it didn't effect the ride of the 1/2 ton truck. Looking forward to see how it handles towing my 28ft travel trailer 690798
Review from a similar RAS RAS in Vehicle Suspension
Worked as expected. Very pleased. 658908
Review from a similar RAS RAS in Vehicle Suspension
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. 654976
Review from a similar RAS RAS in Vehicle Suspension
2018 F150 4x4 owners pay attention to this review. I received the order today and unfortunately it was the wrong kit for my vehicle. Even though etrailer confirmed that a RAS3611-B is correct for my truck, it is actually for a F150 4x2. I contacted etrailer and costumer service rep was great and verified that initially the same part number came up for my vehicle, causing the confusion. My mistake, etrailer mistake. The correct kit for a 2018 Ford F150 4x4 is RAS3611-Y. etrailer is splitting the cost of return shipping and my correct kit has been ordered. etrailer has great costumer service. 567680
Review from a similar RAS RAS in Vehicle Suspension
Worked as described and made a big improvement towing our travel trailer. 526259
Review from a similar RAS RAS in Vehicle Suspension
Repeat customer. Just installed my second set of Roadmaster Active Suspension springs. Have not towed with them yet; however the ride on my 2014 F150 6.5' bed pickup is noticably smoother. I expect the result when I do tow my travel trailer to be the same as with my previous truck - night and day difference (no more "white knuckle towing)! 319927
Review from a similar RAS RAS in Vehicle Suspension
2019 Nissan NV 2500 Cargo van owners please read! Etrailer sent the wrong parts the first time, but they took care of it right away. Their customer service is great and this review should not reflect upon them. The RAS seemed like a good solution to level the vehicle and reduce body roll, so I ordered them and installed. With the RAS at 40% and recalibrated at 40% after a test drive, it seems to do nothing. It does help if the van is totally empty, but who drives around an empty cargo van? I was at about 1/2 of the max payload and it still sagged in the back. I can’t speak for other applications, but this is not a good fit for Nissan NV. You have to remove a leaf spring bolt on this application while installing so it will hook between the spring and shackles. I wound up taking the van to a reputable spring shop and had the leafs built up. It only cost me $100 more than the RAS, and now it drives like it should. 656563
Mike L - 07/25/2019Review from a similar RAS RAS in Vehicle Suspension
High quality components. We installed the Roadmasters on my 2000 Ford Excursion yesterday. The instructions for installation were clear and concise. The installation took about 45 min. A god bit of that time spent on jacking, wheel removal and replacement. Not a particularly difficult installation. My impressions after test drive: I think the ride was slightly harsher than before installation, but nothing significant. The sway control was greatly improved. Surprisingly, the vehicle seems to handle bumps better, and unexpectedly, braking seems better. All in all, a good upgrade at a reasonable price. Jim 563475
Jim E - 09/11/2019Review from a similar RAS RAS in Vehicle Suspension
We received suspension kit yesterday. My husband installed immediately. It took him a little longer than expected. But he is so happy!!! His Toyota Tundra is driving and handling so differently.... in a good way. We have not hooked up to trailer yet but I'm sure we will be totally happy. Good product! 408485
Review from a similar RAS RAS in Vehicle Suspension
I really like the suspension add on. It keeps my truck level when towing our 9000 lb camper bumper pull. I get great stability on the road and it helps with handling the tongue weight on my 2013 Toyota Tundra 1/2 ton. It doesn't change the stiffen the suspension of my truck until I add weight. So, you don't notice it with normal driving. Installation went smoothly. The components were high quality and heavy duty. I recommend it. 577747
Review from a similar RAS RAS in Vehicle Suspension
Mounted on 2015 Tundra ,pull heavy car trailer and toy box these work great and are adjustable. Unlike airbags they won't leak and much easier install. They helped level truck when I'm loaded and resolved some front braking issues with the sensors on these new vehicled. 319138
Review from a similar RAS RAS in Vehicle Suspension
I have had this product a couple of months now with two trips pulling my travel trailer. It has helped in leveling out the truck/trailer so that less pressure is applied to the weight distribution system. Product is easy to install, I didn’t even need to take the tires off. It also is easy to adjust to fit different hitch weight. It did make my truck ride a little ruff but not to a point that is uncomfortable. I chose this product over air type products as I didn’t want to have to mess with it. I would recommend this product. 593932
Review from a similar RAS RAS in Vehicle Suspension
As with many other reviewer's I researched several different brands and types of systems. The springs have helped out immensely with the tongue weight I have to pull with my F-150. I notice a 2 to 3 inch difference in the ride height with the springs on while towing approximately 1200 to 1400 pounds of tongue weight. It also takes out the bouncy feel from truck to trailer on non-smooth roads. The installation is very simple and quick. I highly recommend this product. 443416
Review from a similar RAS RAS in Vehicle Suspension
Easy to install. The Roadmasters did not really change the ride of my 2017 F-150 when not towing. They made it much easier to level the truck when towing. 598577
Review from a similar RAS RAS in Vehicle Suspension
Haven't towed or hauled anything heavy with it yet. Unloaded it does help with body roll in turns. The ride is slightly improved as the truck doesn't bounce as much. 519027
Review from a similar RAS RAS in Vehicle Suspension
For anyone on the fence, I will say it does work well. I'm not sure it is worth it, but that's the price. Also, as others have said, finding your tools is the hardest part of the Installation. 2018 F150 Platinum pulling a 2018 Passport 2920bh 546842
Review from a similar RAS RAS in Vehicle Suspension
I have Nissan 2500 van that I have converted for traveling. Its gross weight is 9000 lbs, and with all that is in it everyday it weighs around 7000 lbs. It has enough weight it sags. I occasionally pull a trailer, which makes the sag even worse. I install the RAS, and it added about 1 1/2 inches to the truck height. I haven't pulled with it yet, but around town it rides great. Maybe, a very slight stiffening of the suspension, but nothing like what Timbren does to a truck. These things were terrible to install. The instructions said there wasn't much clearance on this vehicle, so take apart the unit and put the spring hooks on before lifting the vehicle. I thought I was going to have to unbolt the springs. Using a jack in the right place allowed me to finally getting them into place. It did require much frustration, and some choice language before I finally got them installed. I'm still looking forward to towing with them to see if the sag problem is fixed. I do recommend these. Again on a Nissan van they are a b*tch to install. 650068
Review from a similar RAS RAS in Vehicle Suspension
Excellent product as always from one of my favorite companies. The items (including this one are always as described. This provides leveling for my 2018 F150 while towing and makes a huge different. 654097
Review from a similar RAS RAS in Vehicle Suspension
Thanks I put the springs on today’s. I have one question, I adjusted them to the 20% / one millimeter. Can they be adjusted to the 40% with truck sitting on ground if my trailer still has the bounce in it when hooked, or will I need to lift it off ground to readjust if needed. 590227
Mike L - 12/12/2018Review from a similar RAS RAS in Vehicle Suspension
Delivery was on time and the product was good and ready to go! Jacked up the truck put it on stands and 1hr 30mins later I was driving off for a test run. Works just like it says it would. No body roll, takes off so much smoother, and I did about 40 over those big rolling neighborhood speed bumps and it was super smooth. Before RAS it would have a real bouncy feel over the speed bump now it attack the bump if you know what I mean. I tow a 25' trailer so I can't wait to see how much bounce is taken out when I'm driving over the dippy roads through the mountain pass here in WA. Thanks E-trailer! 313970
Doug D - 11/05/2017Info for this part was:
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