bing tracking image
  1. Vehicle Suspension
  2. Timbren
  3. Bump Stops
  4. Towing/Load Leveling
  5. Rear Axle Suspension Enhancement
  6. Extra Heavy Duty
THIS ITEM IS NOT A FIT FOR
2009 Chrysler 300
Special Savings on Select Timbren Items. See Cart for Savings.
etrailer Installation
We'll connect you with nearby partnered installers who know this exact setup.
Timbren

Timbren Suspension Enhancement System - Severe Service - Rear Axle

Part Number: TDRTT4500
In Stock
$496.65
Retail:$584.30
You Save: $87.65
Vehicle Suspension
Not Confirmed to Fit

2009 Chrysler 300

Will this fit?

To see if this custom-fit item will work for you please tell us what vehicle you'll use it with.

Instant Rebate
zoom in icon
slider vertical icon
zoom out icon
Comment field cannot be left empty.
Name field cannot be left empty.
By submitting this form, you understand and agree to our Terms of Sale, Website Terms of Use and Privacy Policy.

Thank you! Your comment has been submitted successfully. You should be able to view your question/comment here within a few days.

Error submitting comment. Please try again momentarily.

Product Images

In Use/Installed

etrailer Installation
We'll connect you with nearby partnered installers who know this exact setup.
10,000-lb Capacity hollow rubber springs sit above the rear axle to help stabilize and level your vehicle. Provides a comfortable ride by absorbing road shock and improving stability. Ideal for trucks with slide-in campers or an in-bed salt spreader. Great Prices for the best vehicle suspension from Timbren. Timbren Suspension Enhancement System - Severe Service - Rear Axle part number TDRTT4500 can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.
  • All Info
  • Reviews (966)
  • Q & A (0)
  • Videos (3)
  • Photos

Timbren Vehicle Suspension - TDRTT4500

Highlights

  • Custom Fit for Your Vehicle: Mounts to existing attachment points
  • 10,000-lb Load Support: Keeps your truck level and stable when towing or hauling heavy gear.
  • Smoother Ride Under Load: Hollow rubber springs absorb bumps and reduce harsh road shock.
  • Better Control and Handling: Cuts down on sway, squat, and body roll for safer turns and braking.
  • No-Maintenance Setup: Installs in place of bump stops with no air lines, compressors, or drilling.
  • Long-Term Suspension Protection: Helps prevent bottoming out and extends factory suspension life.

Features to know about

Stay Level and Confident: 10,000-lb Rear Suspension Support

Heavy loads can make the rear of your vehicle sag and throw off handling. The Timbren Suspension Enhancement System uses two Aeon hollow rubber springs rated for 10,000 lbs of capacity to keep the rear level and steady under weight. The resistance from the springs works with your factory suspension to improve traction, steering, and braking when hauling campers, spreaders, or heavy cargo in the bed.

Truck with heavy bed load illustrating rear sag before installing Timbren suspension system

Smooth Out Rough Roads: Progressive Rubber Springs

These hollow rubber springs absorb road shock and cushion bumps to create a smoother, more stable ride. Their progressive design collapses along the folds under pressure and becomes more rigid as weight increases, giving you a comfortable ride when light and firm control when loaded. The rubber construction also helps prevent bottoming out on rough surfaces and extends the life of your existing suspension.

Truck driving on a rough road illustrating road shock without Timbren suspension system installed

Animated diagram showing compressed Timbren hollow rubber spring demonstrating progressive resistance design

Stay Steady in Crosswinds and Turns: Independent Spring Action

Each spring works independently to support either side of your vehicle. That means when you swerve, corner, or carry an uneven load, body roll is reduced and stability improves. The system keeps your truck planted through turns or highway gusts while helping minimize trailer sway so everything tracks straighter behind you.

Illustration showing Timbren suspension reducing sag, body roll, and sway during vehicle cornering or uneven loading

Example image showing trailer sway control with Timbren suspension system during towing

Easy, No-Drill Setup: Bolt-On Installation

The kit includes vehicle-specific brackets and hardware that replace the factory bump stops on the frame—no drilling required. The custom-fit brackets bolt directly above the rear axle with about 1" of clearance so your stock suspension operates normally under light loads. It’s a simple design that installs cleanly without compressors, air lines, or manual adjustments to manage.

Diagram comparing loaded versus unloaded positions of Timbren rubber spring above rear axle

Specs

Weight and Capacity

  • Capacity: 10,000 lbs

Included Components

  • Includes: 2 Aeon hollow rubber springs, vehicle-specific brackets and hardware for simple installation

Installation

  • Replaces: axle bump stops on frame
  • Drilling required: No drilling required

Compatibility and Requirements

  • Designed to work with: a suspension system that is in good working order
  • Weight-carrying capacity: Do not exceed the vehicle's weight-carrying capacity

Warranty

  • Warranty: Limited lifetime warranty - satisfaction guarantee

DRTT4500 Timbren SES with Aeon Hollow Rubber Springs - Rear Axle - Severe Service

Installation Details TDRTT4500 Installation instructions

This Product Fits The Following Vehicles




Video of Timbren Suspension Enhancement System - Severe Service - Rear Axle
Video Thumbnail Video Player Dialog

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




Video Transcript for Setting up the Timbren Suspension Enhancement System on your 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 TDRTT4500.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. Now these are going to provide a lot of load leveling support and make sure that we're going to have superior performance whenever we have a heavy load in the back of our Ram. Our Timbrens are going to mount in between our frame and our axle, so that way, whenever we do have that load or heavy trailer and the suspension starts to flex downward, this is going to take up a lot of that force and it's going to absorb it, giving us the support we need.

The single convoluted design, compared to either having two or three, is going to be a lot more aggressive and more responsive when we put our load in, because it's going to have a lot shorter of a deflection curve, which means when we apply our load, it's going to respond more aggressively and be a lot more stiffer, giving us the support whenever we're towing those extremely large trailers or have those big loads in the back of the truck.Our Aeon springs are going to be made out of rubber, so they are going to act as a shock absorber. Whenever we're driving down rough terrain, hitting bumps, it is going to take a lot of that force and not transfer it into the cab of our truck. Now 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, or if we're driving on uneven pavement, as well as help reduce body roll whenever we make a sharp turn or evasive maneuver.Our kit is going to come with both springs and brackets specifically made for our Ram. Now we're not going to have to drill at all and it's going to have all the hardware necessary in order to get it in place. Where our factory jounce stops are really just meant to prevent the truck from bottoming out and the axle coming in contact with the frame, our Timbrens are going to be there to help support and give us that extra strength in our rear suspension.Our Timbrens are going to be rated for 10,000 pounds, but keep in mind they're not going to increase the payload capacity of your Ram.

They're just there to help support your suspension so it doesn't have so much stress and strain on it. You always want to double check the owner's manual and never 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. We can start assembling our springs now.Now if we look on the inside with the large hole, you'll see that there's going to be a washer inside. You want to make sure that it's flat and that it lines up with the hole on the other side. We'll take our spring and our bracket and we'll find the threaded hole on our bracket. Make sure that's facing up. We'll get our spring loosely sitting on top so it's pretty well lined up. You're going to want to grab a 19mm socket and an extension. We can help guide that bolt through that washer and into the bracket. You want to make sure that that washer doesn't move on you and kick to the side and the bolt just go through the spring. You want to make sure it goes all the way through the washer and the spring. It'll take a little bit of wiggling that bolt around, but once you have it lined up and it's coming through the spring, you'll line it up with that weld nut. We'll get it started and we're going to tighten it down to where that spring isn't going to move on the bracket anymore.Now when we go to put our spring in place, it's very important that we pay attention to the bracket. One of them is going to be labeled left, which is going to be the driver side. It's also going to have two holes, one oval hole and a slotted hole. The oval one needs to go towards the front, and the slotted one goes towards the back. You'll notice, in case that sticker did come off, there is an offset. You want your holes to be towards the outside or towards the leaf springs. That way, you know which side the bracket's for.Before we put our bracket all the way up, if we grab one of our bolts, we're going to loosely install it into the rear weld nut where we took our jounce stop out. This'll help hold the bracket in place because it is slotted. We can just slide it in and it will at least hold it up there so we can get the bolt in on the front side. Now that we have both bolts in, we'll come back. Since there's limited space, we'll be using a 16mm ratcheting wrench to tighten up those two bolts.Now that this side is nice and tight, we're going to go ahead and repeat the same process for the other side. That'll finish up your look at the Timbren Rear Suspension Enhancement System, part number TDRTT4500, on our 2016 Ram 4500.

Customer Satisfaction Score:

Ratings & Reviews

4.5

966 reviews
5 Stars
(718)
4 Stars
(137)
3 Stars
(29)
2 Stars
(34)
1 Star
(48)
Review Sort Icon
by:
Wow !!! I got my order ahead of the delivery schedule. And the packages were in one piece. I have been having an issue with some of the delivery people ( USPS, UPS, FEDEX, ) on how the packages I receive come to me. ( Damaged, missing parts, ).
Besides doing the usual repair / maintenance on my 2008 Winnebago Vectra ( 40ft. Class A ), I am gathering parts to build a Ram 5500 into an exploration vehicle.
Funny thing is I started on the Ram 5500 2 months ago and just recently I found pretty much my exact build on YouTube. “ The Cummings Camper “ who is sponsored by etrailer. Most of what is on the YouTube channel I have already implemented but there are several new ideas I need to consider like water filtration from a stream. And I will be ordering my parts from etrailer.
One stop shopping at a good price. And they have what I need in stock.
Nick S. profile picture
Etrailer Expert

Nick S.

1/5/2026

That is awesome to hear! I can understand the struggles with deliveries myself so I am glad this one arrived all good for you. I am very familiar with the Cummings Camper, that is an awesome build. I am starting my track to rebuild a van into a camper so I will be right there with you shortly. How far along are you on the rebuild?

by:
Exactly what I needed. Easy install
by:
by:
Works well on my F250 6.75 bed with a 1700lb dry Capri Retreat camper. Solved 4" squat without airbags. Eliminated sway in high winds.
Heather A. profile picture
Etrailer Expert

Heather A.

5/26/2026

Wow, that is exactly what we love to hear about these springs! That is a serious camper. Any plans with it this summer?

by:
I have Timbrens on an F350. We have a heavy truck camper that we use multiple times a year. I've had both these and airbags on multiple rigs over the years and the Timbrens are superior by far especially because they don't leak at the connections, valves or bags or work loose. They also help with the sway.
There is no pump or electrical involved. Airbags have just too many parts and potential points of failure guaranteed to happen away from home on a muddy road. Once Timbres are installed you're done. In this case the less expensive and simpler solution is the better one!
Tom E. profile picture

Tom E.

8/9/2026

Still working great! No issues. Other than being dirty, they look and perform like new.

Jerred H. profile picture
Etrailer Expert

Jerred H.

8/9/2026

@TomE That's great to hear Tom! Thanks for coming back after a year and sharing that feedback.
by:
2012 Toyota Tundra
Time will tell! Fast and easy install on my 2012 custom flatbed tundra. Hoping this will help when I overload my truck. I have about 900 lbs of extra weight on my truck at all times + Old man Emu heavy duty leaf springs.
by:
Really won't know until I put my truck camper on the vehicle. Product looks and feels quality, we'll see about performance. Installation instructions could be a bit more detailed.
James profile picture

James

7/27/2026

So far they have been fine. They are part of my suspension upgrades, along with stable loads and sway bar. I wasnt worried about harder ride when camper off, I wanted best suspension when camper was on. I would definitely recommend them.

by:
Huge posotive difference felt when towing a fifth wheel trailer. There is still too much gap between the axle tube and the cushion, so Timbren is sending additional hardware at no charge.
by:
2006 Ford F-350 Super Duty
It was tough to remove the stock bump stops on a 06 f350 the new timbrens were straight forward easy to install. They are quite expensive for what they are! I won’t be putting the slide in camper back on until spring so I really won’t know how they will perform but I hope they work as advertised.
by:
Ford F-350 Super Duty
I ran air bags on my previous trucks when pulling my 5th wheel and trailers, but these worked just as well without the expense. I run them on a F350. Great product!!!
by:
2011 Ram 1500
The installation was pretty simple and I’m sure they will work out fine, but I won’t know for sure until the next time I have to take my tractor on the trailer or load up my ATV.
by:
2023 Ford F-350 Super Duty
The Timbrens arrived and install was a breeze. Look to be of very good quality. I went with the severe duty because my truck is always loaded up with camping supplies, electric bikes tools…. The topper on back along with the slide tray are added weight. I pull a 7k travel Trailer with 650-700 pounds on hitch. The Timbrens are barely touching the axel without the trailer. I really enjoy dealing with etrailer. They answer all your questions and always put the customer first. It’s kind of like your project is their project.
Charles profile picture

Charles

2/8/2026

Excellent product. Does exactly what they were designed to do. I removed the sever duty extension. Now the ride is soft when unloaded. But yet smooth when towing or loaded heavy.

Andrew N. profile picture
Etrailer Expert

Andrew N.

2/9/2026

@Charles Nice! I'm glad you are still enjoying them. I had the timbrens on my old Nissan Titan and they did great for the 5 years they were installed for towing my car hauler. I'm curious though, when you say you removed the severe duty extension, are you meaning the rubber spacer?
Charles profile picture

Charles

2/9/2026

@AndrewN Yes sir, with the extra rubber in the ride when empty was a little rough. IMG_6417.jpeg
by:
2016 Ram 1500
They are difficult to seat. Soapy water does nothing to help. I had to spray with silicon,jack up the back of the truck and place 2x4's between the bump stop and the axle,NUMEROUS TIMES.
Once I towed my 5th wheel I noticed the difference. When unloaded, the ride is normal.
by:
Love my Timbrens. Had airbags and was tired of leaks and the need to adjust air pressure. Easy to install!
by:
It would be helpful if the kit contained all the hardware to attach it to the truck. I purchased this to replace a Loadlifter 5000 that was installed 9 years ago. I don’t have the OEM clip and nuts that goes into the frame. It took hours of searching before I finally figured out I could find it on the Ford suspension schematics.
by:
Ram 3500
Do not keep vehicle level. 800 Lb. tongue weight trail still lowers rear of truck approximately 4 inches. 3500 GMC Dually 4x4

My advice is don't be lazy just go with air bags.

They say satisfaction guaranteed defiantly not satisfied and will be less than happy if they charge me a restocking fee on a bad product. I should have known better.
by:
My truck has an added utility body in the bed at all times. Before addinng the Enhancement System I did not feel that I had control of the truck. After adding the system the truck drives much easier and has a "safter" fee.
by:
2026 Ford F-550 Cab and Chassis
Quality product, I have owned Timbrens before. They work good. Installation is fairly easy depending on your skill level. Etrailer as always - great!
by:
2025 Ford F-450 Super Duty
The reality of how long it took to install was misrepresented. I am 74 years old and my wife and I installed these bump stops in about a 2 hour span including rest time. We actually expected that. The results were as promised and I truly appreciate that.
by:
Awesome. They work great. I’m glad I chose this path versus airbags.
Scott profile picture

Scott

5/9/2026

They work great and are holding up well after a year in service on my 2011 F350 SRW hauling my Lance 855 truck camper.

by:
Dodge Ram Pickup
Works very well on my Ram 3500 long box 4x4. Really helped with stability pulling a 2600# tongue weight, 16K Gvw 5th wheel. Super easy install!
Loren profile picture

Loren

3/6/2026

No changes, zero issues or regrets!

by:
2006 Chevrolet Silverado
This review is on a timbren air spring ,I bought this on a Saturday night ,went out of town Monday morning and got in on Thursday afternoon ,wife said the box had arrived Tuesday and put them on this morning on our 2006 Chevy k-3500 ,my guy had the truck in our shop for an oil change and I asked him to put it on, came back 45 min later and he was done with the spring installation and the oil change ! I asked him how hard it was and he said it took him longer to figure out which parts in the kit he needed that the actual install ,said it was about as easy as it gets .Well ,now for the test drive we drove the truck empty ,pretty much as stock ,rode real well.Then we put a Gaylord box that weighed 4506# and drove the truck ,WoW ,What a difference ,truck rode great and handled well ,went over railroad tracks,really handled well and rode great ,I wish I'd have done this years ago ! I highly recommend this product and commend etrailer on their good service and what made me decide to purchase the timbren product was the you-tube video ,after I saw that ,I placed the order ,it looked so simple to install and it went on just like on you-tube
Bryan L. profile picture

Bryan L.

12/11/2017

The air springs have performed flawlessly ,very pleased with the product and performance ! As a matter fact I was recommending this product to a friend the other day.

by:
Package arrived and pretty beat up from shipping, everything was there except the hardware. I sent etrailer an email and Joy T. replied back quickly, got hardware in the mail and I installed today. Great service and quick response!
by:
2014 Ford F-350 Super Duty
Great product,used on 2014 f350 with arctic fox 990,leveled it out,no rear sag
by:
Never mess with airbags again on your truck. These Timbren bump stops are the only way to go. Installation took a total of 10 minutes and they work amazing. No messing with airlines, filling or deflating air bags with complicated installation. I’m towing a 44ft trailer and these Timbren bumps stops are a must. Great product but a little pricey for what they are.
Brandon profile picture

Brandon

5/11/2021

After a year of towing some kind of trailer every week, the bump stops are showing some wear from riding on the bump stop pad on the axle. That being said, they are still working as intended and as good as the day I installed them. After a lot of miles, the only draw back is driving around with no trailer. Normal driving the ride isn’t effected but when you hit a bump in the road you really feel it hit the bump stop. You loose a fair amount of rear suspension travel with these but I’m used to it now.

25
966
true
Show More Reviews

See what our Experts say about this Timbren Vehicle Suspension


Info for this part was:

Employee Jeff D
Installed by:
Jeff D
Employee Jacob T
Video Edited:
Jacob T
Employee Chris R
Video Edited:
Chris R
Employee Mary K
Updated by:
Mary K
Employee Wilson B
Updated by:
Wilson B
Employee Michael B
Updated by:
Michael B
Employee Carrie F
Updated by:
Carrie F
Employee Lincoln B
Updated by:
Lincoln B
Employee Jonathan Y
Video by:
Jonathan Y
Employee Robert C
Test Fit:
Robert C

At etrailer we provide the best information available about the products we sell. We take the quality of our information seriously so that you can get the right part the first time. Let us know if anything is missing or if you have any questions.