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
2020 Ford Explorer
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: TDRTT3520
In Stock
$398.07
Retail:$468.32
You Save: $70.25
Vehicle Suspension
Not Confirmed to Fit

2020 Ford Explorer

Will this fit?

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

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

Videos

etrailer Installation
We'll connect you with nearby partnered installers who know this exact setup.
7,000-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 TDRTT3520 can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.
  • All Info
  • Reviews (966)
  • Q & A (0)
  • Videos (1)
  • Photos

Timbren Vehicle Suspension - TDRTT3520

Highlights

  • Custom Fit for Your Vehicle: Mounts to existing attachment points
  • 7,000-lb Load Support: Keeps your truck level and stable when hauling or towing heavy gear.
  • Smoother, Safer Ride: Rubber springs absorb bumps and road shock for better comfort and control.
  • Prevents Rear-End Sag: Helps maintain steering, braking, and headlight aim under heavy loads.
  • Handles Off-Center Loads: Each spring works independently to steady uneven cargo or sharp turns.
  • No-Drill, Simple Install: Bolts into place using factory mounts with brackets and hardware included.

Features to know about

Stay Level Under Heavy Loads: 7,000-lb Rear Suspension Support

When you load the bed or hitch up a trailer, the rear end naturally wants to sag. The Timbren Suspension Enhancement System adds up to 7,000 lbs of extra support over the rear axle to keep your vehicle level and stable. The hollow rubber springs sit above the axle to share the load with your factory suspension, improving handling and braking while preventing squat and bottoming out. You get a level stance and steady feel when hauling gear, campers, or heavy tools.

Truck with rear sag under heavy bed load demonstrating need for Timbren rear suspension enhancement system

Animation of Timbren rubber spring compressing to increase resistance and maintain level vehicle stance under load

Smooth Ride on Every Trip: Progressive Hollow Rubber Springs

These Aeon hollow rubber springs aren’t just stiff blocks—they’re designed to compress progressively for a comfortable ride. Under light loads, they leave about an inch of clearance so your stock suspension can move freely. Add more weight and they firm up automatically, absorbing road shock and bumps while keeping things smooth and controlled. That progressive action means a supple ride when empty and solid support when loaded down.

Truck on uneven road showing Timbren rubber springs absorbing shock for smoother, stable ride

Diagram of Timbren rubber spring above axle showing space for normal suspension movement when unloaded

Stays in Control Through Turns: Independent Spring Action

Each Timbren spring works on its own side of the vehicle, so you stay balanced even when loads aren’t perfectly centered. This independent action cuts down body roll in corners or during quick maneuvers. When crosswinds hit or a trailer sways, the springs help keep everything lined up by reducing side-to-side movement and keeping your ride stable through curves and sudden lane changes.

Diagram showing Timbren suspension reducing body roll and sway for improved vehicle stability

Truck towing trailer with sway controlled by Timbren suspension enhancement system for safer handling

Built Tough and Easy to Install: Bolt-On Design with No Air Lines

The system includes two hollow rubber springs with vehicle-specific brackets and hardware that bolt to the frame rails above the rear axle—no drilling required. With no air hoses, compressors, or adjustments to worry about, setup is simple and reliable. Once installed, the durable rubber construction helps extend the life of your suspension by taking the brunt of bumps and rough roads while preventing bottoming out over time.

Specs

Included Components

  • Includes: 2 Aeon hollow rubber springs, vehicle-specific brackets and hardware for simple installation
  • Replaces: axle bump stops on frame

Installation

  • Drilling required: No drilling required

Weight and Capacity

  • Capacity: 7,000 lbs

Compatibility and Requirements

  • Vehicle requirements: Designed to work with a suspension system that is in good working order

Warranty

  • Warranty: Limited lifetime warranty - satisfaction guarantee

DRTT3520 Timbren SES with Aeon Hollow Rubber Springs - Rear Axle - Severe Service

Installation Details TDRTT3520 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 Timbren Manufacturer Spotlight - Suspension Enhancement

Hey guys, it's Jake here with etrailer. Today we've got John with us from Timbren. He's gonna tell us a little bit more about what separates Timbren from the competitors. I appreciate it, I'm glad to be here. Timbren is a suspension specialist. We're based in Whitby, Ontario, so we are a true manufacturer in Canada and we offer a wide range of suspension products from light duty, from commercial all the way up to Overlander, Sprinter applications and trailers.

Now we've talked about a few of the options you guys have and we have plenty of options on our website. Right. We've got the SES kits. We've got the axle-less suspension. Right.

We've got your new coil inserts that just came out recently. But what would you say is your bread-and-butter at Timbren Yeah, no, our SES, suspension enhancement system, is definitely our bread-and-butter. Came out in 2011, won a SEMA New Product Award for best truck suspension. And really, the evolution you just mentioned here, you know, starting in 1968 all the way through now, 2024. But the SES kits are really the core of who we are.

And if you, if you would say at, in the level of stiffness on the market, what would you, would you put yourself in more in a heavy duty side for the SES kits or is it more of a lighter duty Yeah, great question. Lighter duty, we certainly can have a product for commercial and heavy duty, but in '82 when SES was introduced, it was purposely introduced for that, that light duty market. So we start with 1500 and again, go all the way up, but by far really popular with that 1500, 2500 crowd. That kinda leads me into my next question. So we talked about, your specialty is kind of in the lighter duty, but do you have an option for the heavier duty for your sprinter vans and maybe for your truck bed campers Yeah, absolutely.

We do have SES kits for truck beds, truck campers with a higher center of gravity. That creates a new kind of set of problems with the sway side to side. So we have severe duty kits for those. And it uses a single convoluted AON versus a double convoluted to tackle that problem of side to side. And the same thing with the sprinter van. It uses a rectangular shape Aon, but it's there to do the same deal that side to side sway because they're so top heavy, it'll eliminate that. Okay. And then we've had an instance here at etrailer that we had a van that was very, very heavy on the one side. Is there anything that you guys can do personally to help, I would say, I guess customize that kit for that particular user Yeah, by all means we would want that individual to contact us. We would ask a couple questions, see where that weight is distributed and we can actually produce an AON with either a stiffer hardness or durometer or a softer durometer and that will help level it out. So yes, we can take care of that for 'em. And I think that'll really, really help people to get their rigs dialed in because who knows what they're putting in the campers afterwards, after they buy 'em. They come from the manufacturer already heavy on that side and they're trying to load stuff on the other side to try to even it out. But knowing that there's a solution that you can customize for your rig no matter what the weight is on either side is really, really cool. Yeah, absolutely. We're happy to take care of 'em and again, there's no charge for that. Awesome. Now to kind of wrap things up, what sets Timbren apart from a lot of other manufacturers out there Well, I think there's a couple things. We're a family run company and our longevity, you can't deny, 1968 to 2024 and our warranty, we have a lifetime warranty regardless of how old it is. We will take care of it, replace it, limited lifetime warranty, and the hundred day money back guarantee. Very cool. And that's whether or not you're the first owner Right. And yeah, we're not asking for receipt, who'd you buy it from It'll be taken care of. Just give us a ring and we'll take care of it for you. Very cool. Well thank you again for meeting with us. Appreciate it. It was a pleasure to work with you. Thank you.

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:
It works exactly as you would think. I was expecting a much harsher ride when the trailer was hooked up but the rubber they used offers a decent ride. With no trailer the ride is no different.
by:
1996 Dodge Ram Pickup
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:
I have a 2300 pound truck camper. I drove before the Timbrens and after. Felt like a completely different truck after. Felt as good as my old truck with airbags for half the price.
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 Dustin K
Video Edited:
Dustin K
Employee Chris R
Video Edited:
Chris R
Employee Mary K
Updated by:
Mary K
Employee Wilson B
Updated by:
Wilson 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
Installed by:
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.


Product Experts Available Now!
Call 1-800-940-8924