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When you drop a load in the bed or hook up a trailer, the rear shouldn’t sag and throw off your control. This RoadActive Suspension kit adds up to 3,000 lbs of support by converting your leaf springs into a mechanically active system. It automatically strengthens and adjusts to the weight so the truck stays level, steering stays tight, and braking feels confident even under heavy tongue weight or bed loads.
Sway and bounce can make towing or hauling stressful. Each RAS unit uses variable-rated coil tension springs that instantly react to weight transfer before sway or squat ever starts. The design eliminates axle wrap and wheel hop while reducing side-to-side body roll through curves or gusty winds. The result is a balanced, planted feel on the highway or back roads with no harsh ride when unloaded.
Once installed, there’s nothing to adjust or monitor. The RAS kit bolts directly under the factory leaf spring using the included brackets—no welding, drilling, or cutting required. The system comes fully assembled, tensions can be preset during installation with included spacers, and it stays maintenance-free for everyday use or long hauls.
Long days on salted roads or in wet conditions won’t slow it down. The heavy-duty alloy steel springs are epoxy e-coated for corrosion resistance, and the brackets carry a salt spray rating of more than 800 hours. By taking strain off your leaf springs, shocks, shackles, and tires, this setup helps extend component life while keeping your suspension strong mile after mile.
Customer Satisfaction Score:
91% were satisfied with this product
9% of customers were not satisfied
Ratings & Reviews
Can't say enough good about the RAS, put it on my Silverado 2500HD with a Spacekap Diablo on back, the RAS brought the ride back to same as stock. Even with a top heavy load there is no more sway than stock and it brought the ride height back to stock. Love the RAS.
Does exactly as described. When loaded up with a 5th wheel camper that weighs 10k hooked to a 2000 f250 you can not even tell it’s back there when going down the road
Received these ahead of schedule and all intact. I watched the video on etrailer.com and youtube, very helpful.
The installation is not difficult if you are handy with tools. Aside from it deciding to rain on me during install it was not bad. Suggest you lay out all your tools and include a couple of adjustable wrenches. First off, unscrew that gold screw alot, when you think there is enough, go more, the first side I was short. I wiped down the truck springs to remove any dirt there and set up then tightened by hand, you can't go far that way but gets you started. On the rod with the 2 nuts that will lock together when done, I gave myself about 3" of thread and locked them together to hold the threaded rod while adjusting, no way to hold the end nut, this worked out well. The one thing I would have done different is the adjusting nut is 14mm, I only have a 6" ratcheting 14mm, doable but at the end it tough, I wish I had a 10" or so, there was space in my install. I set mine to high since I pull a 5th wheel so adjusting was the hard part.
I will not know until spring if this helps with the towing as the camper is now stored but very hopeful from others input. If anything changes I will update.
Gary
10/17/2024
These worked out very well, helped with stabilizing the 5th Wheel camper while pulling and did not cause a harsh ride while unloaded.
Works great for what I need to do
Installed this system on a 1999 F-250 SD. I pull a 35 foot 5th wheel trailer that has a pin weight of 2,180 lbs. (I know the exact weights as I have weighed each axle, unloaded and loaded.) Before the RAS install, the trailer would cause the rear of the truck to sag, pitching the nose up just a bit.
I installed the RAS system, and knowing my truck is loaded to the max, I decided to use the 2mm spacer. After the install, the height at the rear bumper was 2 1/4 inches higher. Before the RAS install, the trailer would cause the rear of the truck to drop a full 4 inches. With the 2mm spacer adjusted RAS, the trailer caused the truck to drop about 2 inches in the rear, but the rake of the truck now remains with the nose lower than the rear.
After the initial install, I drove the truck unloaded. The ride was about the same as before, maybe just a bit smoother, hard to say for sure.
This past weekend, we took the truck and trailer to Branson, MO and back, about a 825 mile round trip. What a difference! We hadn't driven 2 miles from home when the wife said, wow, this is a different truck. The ride was fantastic. It eliminated surging we would sometimes encounter on some roads. Bumps and undulations in the road were so much better.
I was really skeptical about this, especially considering the price. But you couldn't pay me to take it off now. I consider the RAS essential equipment now, right up there with EGT and boost gauges, 4" exhaust, diesel brake and added TPMS to all tires. I've been pulling that same 5th wheel for 22 years with that 25 year old truck, and this last weekend was the best pull I've ever experienced. Just wish I had had the RAS on the Alaska highway a few years ago. I am amazed at the improved ride. Couldn't recommend it any higher.
Nathan A.
11/17/2024
After numerous trips with the 5th wheel over the past year, along with some fully loaded solo trips, my opinion of the RAS system remains the same Fantastic! I highly recommend the RAS system. Wish I had had it years ago.
Easy to install and it made a big difference in the way my F150 rides while towing. The ride is supple and less jarring than before. My trailer has a 900+lb tongue weight when loaded and the truck and trailer sit level with the RAS system even before the weight distribution hitch is engaged. I was able to use lower settings on my hitch which puts less stress on my trailer frame. When I’m not towing the truck rides like it did when it was fresh from the factory.
These made a significant difference n reducing rear sag on my 2021 GMC 2500HD when loaded for camping and towing travel trailer
Len
8/9/2025
Fine, but the product needs better rust resistance. Powder coating???
Love this product. I ordered a set for myself just before Christmas and I was so impressed that I ordered another set for my son’s truck. I was kind of worried that it would raise rear end too much but that wasn’t the case at all. If it raised it at all, it wasn’t noticeable. Definite improvement in handling bumps, cornering, and it eliminated any squat due to my pin weight of the 5th wheel. Highly recommend for an easy install (45 minutes) and overall ride improvement.
Super quick install and I'm more confident towing my heavier camper now.
This is my 2nd set of RAS! Just purchased for towing in my D-Max 2500HD. 1st set we’re on a Chevy 1500. I tow a 7000lb 259FKDS Freedom Express bumper pull and having the RAS-HD’s installed is night and day difference in towing. I have them set at 40% because of my cargo in the truck bed and tongue weight. I’m set up right now as I type on a 100 mile camping trip to set the springs and readjust if needed! So I say….”if you need support with towing, give RAS3611-HD a try…you won’t be disappointed with the results”
Installed for nearly 6 months now. I love this suspension! I needed something to give my '18 Titan some heft in the back end when pulling our 24' RV trailer but didn't want to deal with any of the air options out there. After reading the directions twice, I installed both sides before the AC/DC album was finished playing, so it's super fast and easy. I set them on 25% tension and really like how they drastically reduce porpoising during our RV drives. Well worth the cost.
I have a 2002 2500hd and pull a trailer that puts has a 1400b tongue weight. Adding the RAS enhancement kit has made a big difference in the way my pickup handles the load. Much safer and controlled. They were very easy to install which I did myself. I would highly recommend them for anyone who has a trailer with a heavy tongue weight.
Gwendolyn Y.
6/3/2025
Knowing that your drive is safer is great to hear, Les! Are you towing a toy hauler, utility, camper?
I tow a 7500 lb Airstream with a Chevy Silverado 2500HD. Prior to installing the RAS, I had an issue with porpoising. That was no longer a problem after I installed the RAS. Porpoising was dampened and controlled with RAS.
Bret
11/15/2025
I loved turn, but I traded trucks and now I cant use them anymore because of the overload springs on my 2025 Chevy 2500HD.
Silverado 2500HD
Ready to install out of the box. Simply extend the RAS out to become the proper length (shortened for shipping), remove the bolt to allow the fork to drop over the leaf spring and reconnect, hand tighten the assembly via turning the spring and check the "centered alignment", then tighten with a wrench (my socket wouldn't quite fit) until gap disc slips freely between the expanded spring. Took me longer to prep truck on a jack and two axle stands/remove tires for improved accessibility than the actual RAS installations.
Added 1 inch of lift "empty weight". Will see how much squat is removed under load of our travel trailer this weekend!
I'm not very mechanically inclined, and found this very easy to self-install - a level 1 project.
NOTE: etrailer customer service also took their time w/ me over the phone to ensure I had ordered the proper kit for my vehicle, and although my order was sent to the vendor for direct shipment, I got it to Alaska in less than 10 days.
Fast shipping, easy install
RAS HAS BEEN ON MY C-20 3/4 ton chevy for a year. I am able to haul four pallets of newspapers without bottoming out and ruining new tires.
It does as advertised. So…5 stars!
Bruce
4/29/2026
Still a two thumbs up! Keeps my load to the front, my steer tires on the ground, and my lights out of oncoming drivers’ eyes. Safe all around!
These leaf springs were the right size and very easy to install.
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!
Keith
8/27/2023
Its been really wonderful. 10k 5er on my 07 2500hd classic ccsb and I can definitely notice an improvement in handling, including less porpoising. Towed it a couple times since, including a 7 hour drive. Very happy. I recently replaced the old wornout front bumpstops with sumo springs monsters and saw additional improvement. Neither hurts the unloaded ride, just better all around!
Haven't trailered with these installed yet but they installed easy and gives a nice ride. Will update once we start trailering.
Worked well on leveling 1,000 lb tongue weight
Robert
3/26/2026
Item continues to work well for what it was designed.
Lazer S.
3/26/2026
Total transformation! I never knew how bad my ride was until I installed these RoadMaster 3611-HD active suspension. It took longer to safely jack my truck up and remove tires than it was to install them! Absolutely a game changer. I carry about 1000 lbs of tools and supplies daily and like riding a Rollercoaster when hitting bumps. Now, i hit bumps on purpose just to feel these RoadMasters work their magic! Love them!
Tracey T.
4/29/2022
After a year of use , these RoadMaster 3611-HD active suspensions are still the best addition to my trucks performance. The streets of Houston are brutal and these active suspension breeze through them. I have 354000 on this truck and if I ever get another, this Active Suspension will be the first addition. Hands down!
My husband had some trouble woth the first one with the spring but they are amazing truck didnt move an inch when we put our 5th wheel on it amazing.
Works great at leveling my truck with my travel trailer.
Paul
7/23/2025
It has worked out very well. Actually, better than I expected.
I have heard nothing but good things about these enhancement springs so I bought a set. Very easy to install if you have any mechanical ability at all. Haven't used my truck to pull out 5th wheel RV yet but I will in a couple of days. I have a 2500HD it seems to have soften the ride a little. It doesn't make sense but prior to instillation it rode rough like it should, but the springs seem to help. IDK
Finally decided to try the RAS system for the truck since I bought a bigger camper. Ordered it hoping it would get here in time for an install before our new camping trip. Arrived in plenty of time! Opened it up and went through the instructions and got to the install. So, advice…read instructions from start to finish before starting! LOL. I thought they sent the wrong parts and then I read the instructions completely and then said, oh yea, forgot that part. Ha ha. Anyway, there's always a better way to do things based on your situation and vehicle. So after a few different attempts, finally got my groove and install went just fine. As always…take your time, double check everything before tightening down! Anyway, completed the install and then took it for a quick drive. Real happy with it! Felt substantially like it can handle more weight. Will be trying it with the camper next week. Again, thanks to the etrailer peeps for getting it to me on time. Since Murphy's Law resides in my garage, I wanted plenty of time to do the install right…and they delivered! Literally. Thanks again and will look forward to the next order.
Victoria H.
3/12/2025
That's awesome Michael! I'm glad these made a noticeable different in your ride quality. Thank for including your valuable insight with your feedback along with the photos! I know this will be very helpful information to someone gearing up to install these in the future!
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Dana
3/17/2025
still love it, working the same, makes the truck ride like it doesnt have 1100 pounds in the back.