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Timbren Rear Suspension Enhancement System

Timbren Rear Suspension Enhancement System

Item # TDR5500
Our Price: $465.47
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12,000-lb Capacity. These hollow rubber springs sit above the rear axle to help stabilize and level your vehicle. They also provide a more comfortable ride by absorbing road shock and improving roll stability. Easy to install and use. Great Prices for the best vehicle suspension from Timbren. Timbren Rear Suspension Enhancement System part number TDR5500 can be ordered online at or call 1-800-496-5010 for expert service.
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Timbren Vehicle Suspension - TDR5500

  • Jounce-Style Springs
  • Rear Axle Suspension Enhancement
  • Timbren
  • Extra Heavy Duty

12,000-lb Capacity. These hollow rubber springs sit above the rear axle to help stabilize and level your vehicle. They also provide a more comfortable ride by absorbing road shock and improving roll stability. Easy to install and use.


  • Improves suspension, handling and safety
  • Provides additional support as needed so you always have a smooth, comfortable ride
    • Allows the leaf spring ample movement while cushioning light loads
    • Becomes more rigid as more weight is added
      • Increases stability - providing great performance while hauling heavy loads
      • Reduces vehicle sag
  • Works independently - side-to-side
    • Helps compensate for off-center loads
    • Reduces body roll when swerving and turning corners
  • Acts as shock absorbers, taking the brunt of bumps and rough roads
    • Extends the life of your vehicle's suspension


  • Includes 2 Aeon hollow rubber springs, vehicle-specific brackets and hardware for simple installation
    • Replaces axle bump stops on frame
    • No drilling required
  • Capacity: 12,000 lbs
    • Do not exceed the vehicle's weight-carrying capacity
  • Designed to work with a suspension system that is in good working order
  • Limited lifetime warranty - satisfaction guarantee

An example of sag on a truck's rear axle under a heavy load. The Timbren Suspension Enhancement System levels the vehicle.

When hauling heavy loads in the cargo area or by pulling a trailer, you will often see the rear of the vehicle sag while the front end rises. In these cases, the rear axle is handling not only the weight of the cargo, but more of the vehicle's weight as well. Because less weight is on the front axle, the front tires are making less contact with the road. Overall vehicle handling - traction, steering, and braking - is negatively affected. The resistance from Timbren's Suspension Enhancement System works with the vehicle's factory suspension to keep the vehicle level and improve your driving performance.

Diagram of the Timbren spring installed

The Timbren system has a vehicle-specific bracket that will be bolted onto each frame rail above the rear axle. Hollow rubber springs are bolted to the bottom of the bracket and hang down to where the bottom of the spring sits one inch above the axle. The inch of clearance allows the existing factory suspension to operate normally under light loads and standard terrain, ensuring the smooth, comfortable ride you are used to.

Animation of a standard Timbren rubber spring

Timbren Suspension Enhancement Systems are designed to work progressively. When the hollow rubber springs are compressed, the convoluted design causes them to quickly collapse along the folds. Once the folds are compacted, the stacked barrel shape provides increased resistance, stiffening the suspension and keeping the vehicle level.

Timbren suspension system works to prevent body roll

Each hollow rubber spring works independently to support the driver's or passenger's side of the vehicle. This is helpful when you swerve or make sharp turns. Each spring is activated when it is needed, so body roll is greatly reduced. The independent action also works well when hauling off-center loads.

An example of a trailers swaying

Because the vehicle handles better with the springs, less turbulence will be passed along to the trailer helping to keep the trailer in line. Your driving comfort is further enhanced if the trailer does begin to sway (from a gust of wind or passing of a semi) because the movement from the trailer is not transferred to the vehicle. This also works to make the sway subside quicker.

An empty truck on a bumpy road without Timbren

Another great feature of the rubber construction is that the springs absorb most of the road shock, creating a smoother, more stable ride overall. Wear and tear on the factory suspension is also lessened as the rubber springs work to prevent bottoming out on rough roads.

Compared to the competition:

Timbren's suspension enhancement systems are much easier to install than air springs - no air hoses are needed to be run, no compressors or gauges to hook up, and no manual adjustments necessary. The rubber construction causes Timbren's springs to be more elastic than similar products constructed of micro-cellular urethane. More elasticity allows for a more comfortable ride because the rubber has more travel.

DR5500 - Rear Suspension Enhancement System with Aeon Hollow Rubber Springs by Timbren

Installation Details TDR5500 Installation instructions

This Product Fits The Following Vehicles

Video of Timbren Rear Suspension Enhancement System

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.

Video Transcript for Timbren Rear Suspension Enhancement System Installation - 2016 Ram 4500

Speaker 1: Today on our 2016 Ram 4500 we're going to be taking a look at and showing how to install the Timbren Rear Suspension Enhancement System, part number TDR5500.If you ever hauled a heavy load or had a big trailer behind your Ram, you've probably experienced what a lot of us do where the backend starts to squat down and we may get a little bit of sway and some body roll back there. When that squatting happens, we're putting a lot of unwanted strain and stress on the rear suspension. It's going to wear things out over time, and really, our tires aren't where they should be and our suspension isn't where it should be either. Since the backend is getting pushed down, the front end is getting lifted up slightly, which means our tires aren't going to make full contact, we're going to have irregular tire wear, as well as our headlights being out of alignment.But upgrading the rear suspension is definitely going to help with that. It's going to support the load back here and keep our suspension where it should be, nice and level. And it's going to prevent as much squatting.

It's also going to help with body roll because it's going to be able to counteract that and not sway so much. Since it's not pushing down so hard and we have that extra support in the back, it's not lifting up so much in the front so we'll have better tire wear, better steering response, and our headlights will be realigned.Now that we've gone over some of the benefits and seen what they look like, let's show you how to get them installed. Here's what our Timbrens look like once we have them installed. These are going to provide us a lot better performance when we're hauling a heavy load or towing a heavy trailer because these are going to give us a lot more support and not solely rely on the rear suspension. Our Timbrens are going to mount in between the frame and the axle and provide support whenever the suspension starts to drop down.

When we're unloaded, it's not going to affect the ride quality because it's not coming in contact. But once it does, it's going to engage softly in the beginning. As it becomes more compressed, it's going to become stiffer, having a progressive rate.If we compare our factory jounce stops to our Timbrens, you can see there's quite a bit of size difference. Now what the Timbrens is going to do is, again, provide that support, while our factory jounce stops are really just there to prevent the truck from bottoming out and the axle from hitting the frame.Our springs are going to be made out of rubber so they're going to have a little bit of give to them but a lot of support. They're going to act as a shock absorber so we can have a more comfortable ride and not have to worry about the bumps and uneven terrain as much.

Our springs are going to work independently from each other from side to side, so it's going to help out a lot with those off-center loads. It's also going to help out with a lot of swaying that we may get from our trailer. Or if we go to make a sharp turn or any evasive maneuver, it's going to cut down a lot on that body roll.In our kit we're going to get two rubber springs, as well as the vehicle-specific brackets. We're not going to have to drill anything in order to get them installed. Our Timbrens are going to have a 12,000 pound capacity, but keep in mind these are not intended to increase the payload of your truck.

They're just there for extra support. So you never want to exceed the manufacturer's recommended weight.To begin our installation we're going to come to the rear axle. Right above that we'll have our factory jounce stop. I already went ahead and sprayed a little bit of spray lubricant on there, but it's always a good idea to soak it down because these bolts can rust because there's really not anything protecting them, especially if you have a salt truck like we have here.Then you're going to want to grab a 16mm socket and there's going to be a bolt on the backside as well as on the front of our bump stop holding it in place. We'll pull those out. Then you want to hold onto the hardware because we are going to reuse it. Now we can get ready to assemble the spring assembly.If we look inside the bottom of the large hole in our Aeon spring, you'll see that there's a washer inside of there. We're going to want to take our long bolt. You want to pass it through the spring so it comes out on the other side. But you want to make sure that it goes through that washer as well. It can be a little tricky. What I try to do is I just drop the bolt in so it'll land straight up, and maneuver it around with my finger to where it will drop through and engage that washer. You can see it's going to come out the other end. Then we'll take our spacer, slide that over the bolt. Then finally, we're going to have the top plate. There's going to be a weld nut inside of here. We're going to want to get an extension and a socket so we can attach all these pieces together.Now the easiest way I found to do it is if we take our assembly and we'll drop it down, get it as close as possible to lined up, then we'll take a 9/16 socket and extension and go through the spring and thread it into the bracket. You want to get that bolt tight enough to where it's not going to be moving around. You can see if you look inside the bracket that we have threaded the bolt going through the weld nut, and our Aeon spring's not spinning around, or our spacer block.Whenever you get ready to install these, you want to make sure you have the correct bracket, and it's facing the right direction. The oval hole that's solid is going to be going towards the front of your truck, and the slotted one is going to be going towards the back. Now you'll also notice that it's slightly offset from center. You want the holes to be towards the outside of the truck. It is going to be labeled. We'll have left with an arrow pointing front.Now to help us get these in place so we don't have to hold everything and try to thread the bolts in at the same time, if we take our bolt, we're going to thread it in a good way on the very back hole. That's where the slot in our bracket's going to come into play. We can just slide the bracket over the bolt and it'll hold itself up while we get the other one in place. We can come back with that same 16mm socket and snug up our hardware. Since we have limited space, you can fit a ratcheting wrench in here to tighten up that last bolt. Now that we have this side on, we're going to go ahead and repeat that for the other side as well. That'll finish up your look at the Timbren Rear Suspension Enhancement System, part number TDR5500, on our 2016 Ram 4500.

Customer Satisfaction Score:

Customer Reviews

Timbren Rear Suspension Enhancement System - TDR5500

Average Customer Rating:  4.7 out of 5 stars   (4678 Customer Reviews)

12,000-lb Capacity. These hollow rubber springs sit above the rear axle to help stabilize and level your vehicle. They also provide a more comfortable ride by absorbing road shock and improving roll stability. Easy to install and use.


I have a ram 5500 rollback towtruck it works great no more draging or saggin even with heavy loads has the truck level


We’ve had airbags, super springs, and these timbren poly bump stops. I will only use these from now on! They are awesome!

2016 Ram 5500

Very easy install really leveled out the truck while towing


2021 Ram 5500

2019 Ram 5500


2012 Ram 5500

2021 Dynamax Isata 5 Motorhome


Review from a similar Timbren Aeon Spring System in Vehicle Suspension

About a 1/2 inch difference in gap at the bump stop perch but still within parameters. Truck sits perfect with trailer attached. Haven’t towed yet. After towing if they perform like they should will upgrade to a 5 star. Easy to install, definitely needed 2x4 and jack. 2011 Silverado ext cab with 30 ft Genisis 5th wheel.


Review from a similar Timbren Aeon Spring System in Vehicle Suspension

I have used Timberns on 2 other vehicles, a Toyota 4Runner and an S10 Blazer with out complaint.

I transport RVs as a contractor for an RV transport company. My truck is 2021 Ram 3500 crew cab, 6.7 diesel.

Because the weight of the units is different with each unit I haul I wanted an easy, no maintenance solution to maintain as level a ride as possible. I haul both bumper pull and 5th wheel units. In addition to the weight of the unit I'm hauling I can carry 110 gallons of fuel with both the factory fuel tank and my auxiliary tank. Additionally, there is the weight of my Curt 25K 5th wheel hitch, Curt 14K equalizer hitch and bars, and approximately 300 pounds in tools.

I don't have to worry about airbags not inflating. The suspension settles about an inch before making contact with the Timberns. Squat while loaded is negligible. The ride empty is the same as it was before installation. The ride loaded is smooth and controlled even when hitting large bumps at highway speeds.

Installation was simple and straightforward. It took me about a half hour.


Review from a similar Timbren Aeon Spring System in Vehicle Suspension

They definitely support and did lift my 2014 toyota tundra up about 1.5 inches.
This application with my weight has trunk riding on the cushions all the time.
That has teavel and bounce issues that do make some driving situations interesting.
I may go ahead and replace with airbags but for now support things well!


Review from a similar Timbren Aeon Spring System in Vehicle Suspension

Makes my truck feel better while towing a 5th wheel camper, especially over expansion joints of the expressway.


Review from a similar Timbren Aeon Spring System in Vehicle Suspension

I think I will be very happy with the ride when I tow our fifth wheel, it definitely needed the extra support especially on rough roads.I chose not to use the spacers because I like the softer ride when the truck is unloaded.


Review from a similar Timbren Aeon Spring System in Vehicle Suspension

The timbrens actually did what they were suppose to do. However, once I starter driving out west I notice the timbrens were riding on the axle which cause the speedometer to jump around depending on the road. I would recommend them if you are hauling or towing a camper or RV. I was going to contact etrailer about maybe removing a spacer for one set however the other set came as one unit. The bottom line is the Timbrens does stabilize your load for safe travels. I will be contacting etrailer soon to assist in correcting the problem...Road trip from Idaho,Colorado,Wyoming,and Utah were beautiful... Thank you etrailer


Review from a similar Timbren Aeon Spring System in Vehicle Suspension

I haven’t hooked up to the fifth wheel yet or else it might be a 5 star. Based on the 15 minute installation time and the price compared to air bags this appears to be a logical way to go. I will update this as I hook up and put a load on it.


Review from a similar Timbren Aeon Spring System in Vehicle Suspension

Haven’t had it on long, but so far so good. 1999 F350 dually. Bolted up nicely. Total job took 10 minutes. Have hauled two gooseneck loads of hay and truck drives SO much better. Nice and level. Money well spent so far.


Review from a similar Timbren Aeon Spring System in Vehicle Suspension

I have the timbren enhancement system on my 2020 canyon. I haul a trailer with Ranger that I pull about 250 miles to hunting camp. It tows great!


Review from a similar Timbren Aeon Spring System in Vehicle Suspension

The Timbren rear suspension enhancement system helped with the truck swaying side to side when the slide in camper is on the truck.
The photos show right and left rear with Timbren’s installed (2 photos), with slide in camper on the truck (2 photos) and when the camper was removed (2photos).


Review from a similar Timbren Aeon Spring System in Vehicle Suspension

Installed these with only one issue, which was on the driver side rear axle. The axle had a ABS sensor cable bracket on the axle that need to be readjusted and trimmed down. The BumpStock was hitting this bracket on one edge. So actually, it's not and exact fit. But this issue is really a FORD placement issue of that cable. So just be aware that some extra work may be needed to install them. Passenger rear side install perfectly. Next is the drive to see how much better the coach drives, heard great reviews on that


Review from a similar Timbren Aeon Spring System in Vehicle Suspension

Great product, it works perfect on my truck. Sometimes I tow up to 30k lbs including my trailer and my truck stays level. No more high beam flashing in my eyes from drivers going in the opposite direction on the road.


Review from a similar Timbren Aeon Spring System in Vehicle Suspension

Worked great on our 2019 Honda Odyssey Elite to the East coast.Fully loaded with 4 people and a car top carrier,the Timbrens kept the van stable and level.
Sold the 2019 but took the Timbren system out and put them in our new 2022 Elite. Very easy to install, highly recommend.


Review from a similar Timbren Aeon Spring System in Vehicle Suspension

I used this on my Isuzu tow truck. The blocks in and of themselves are fine, they support the weight. Here's the problem: They are pre-loaded, meaning that they always touch between the frame and the rear axle. As you load the vehicle this puts more pressure on the frame in this 5" area where the blocks are. The springs have not yet taken as much weight as they normally would. Now, all this upward pinpoint pressure bends the frame. This is what happened to me on my rollback tow truck. After many hours and now double plating the frame all is well again, but a tremendous amount of work. Yes, the blocks are fine, but the result of installing this product resulted in a bent frame. The vehicle was not overloaded and was within the GVWR.

I have reached out to the manufacturer who will be reaching out to you.
-- Etrailer Expert Jenny N - 01/20/2022


Review from a similar Timbren Aeon Spring System in Vehicle Suspension

I will say they are perfect for towing but when your not towing cause they are so close to the bottom it feels stiffer when not towing! They should make long enough so that it touches besides that these are perfect


Review from a similar Timbren Aeon Spring System in Vehicle Suspension

Too early to give a ride review but I received the TFFF53B fronts and the TFRF53A rears for my 2019 Fleetwood Southwind 35K while at a campground this week. Easy enough to change out while there. It is about.a 2 hour job to change out all 4. The front right took me the longest and you have to reuse the existing bolt. A washer should be provided because the hole in the bracket is almost as large as the bolt head. I will be placing a large flat washer there. The rears took less time to change.. I used the first and third slots in the mounting brackets and they actually put the unit more over the center of the axle than the original bump stops. Same was true in the front. No clearance issue or interference with my trac bar.

Have had these on my RV for over a year nowhere and I am completely satisfied. The fact that these always maintain contact with the axles greatly reduce body roll on turns and uneven roads.
Patrick - 11/07/2022

Show More Reviews

See what our Experts say about this Timbren Vehicle Suspension

  • How Does Timbren Suspension Enhancement Weight Capacity Affect Vehicle Weight Capacity
    The weight capacity for the suspension enhancement kits we offer can be confusing in how it's listed but basically the kits provide their capacity in additional suspension support. So it adds that much support to the vehicle's capacity already listed. For example the part # TDR5500 would add an additional 12,000 lbs of suspension support to the vehicle. Now to make things even further confusing (hopefully not) this does not actually give the vehicle more weight carrying capacity. It just...
    view full answer...
  • Recommended Suspension Enhancement For 2016 Ram 5500
    The Vin number doesn't help me find your current capacities, but I have the information needed to help with a solution. We have suspension enhancement systems that work with your current suspension to help with support and reduce sag. Your current payload is between 10,000 lbs and 12,300 lbs. So your current leaf springs are between 5,000 and 6,000 lbs minimum. I recommend the Timbren Rear Suspension Enhancement System # TDR5500 for the rear of your 2016 Ram 5500. This is a confirmed...
    view full answer...
  • Fit and Compatibility of Timbren Rear Suspension Enhancement on a 2015 Ram 5500 Cab and Chassis
    I confirmed with Timbren that the # TDR5500 is indeed the correct suspension enhancement spring for your 2015 Ram 5500 Cab and Chassis. The contents of the kit are designed for the stop over the axle as seen in the attached diagram. This kit includes 2 aeon rubber springs. The # TDR5500 can be installed whether you vehicle was equipped with or without factory top overload springs. What it sounds like you are describing is the upper overload springs. The Torklift # TLA7200 is a good...
    view full answer...
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  • Suspension Enhancement for 4-WD 2021 Dynamax Isata 5 Motorhome 28SS Built on Ram 5500 Chassis
    I suggest the Timbren Rear Suspension Enhancement System, # TDR550. These hollow rubber springs sit above the rear axle to help stabilize and level your Dynamax Isata 5 Motorhome. Because they work independently, the side-to-side movement helps to compensate for off-center loads. For the front suspension, I suggest the Timbren Front Suspension Enhancement System, # TUMDF70. These front hollow rubber springs help to stabilize and level your Dynamax Isata 5 Motorhome and provide a more...
    view full answer...
  • Suspension Enhancement for Front and Rear of 2020 Dynamax Isata 5 Super C Motorhome
    For your 2020 Dynamax Isata 5 I recommend using the Timbren Front Suspension Enhancement System # TDF5500. This system will better serve your suspension as the majority of your added weight is over the rear axle. The # TDF5500HD is more designed for your severe service vehicles like tow trucks and vehicles that will have large plows mounted on them. For the rear I recommend the Timbren Rear Suspension Enhancement System # TDR5500. This will offer you more stability at 12,000lbs versus...
    view full answer...

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Info for this part was:

Employee Jackie C
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Employee Jeff D
Installed by:
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Employee Jacob T
Video Edited:
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