9 minute read
SUMOSPRINGS FOR THE 5TH GEN 4RUNNER
COMPLETE INSTALL & OVERVIEW
By Brenan Greene Owner/Editor of Trail4Runner.com
SumoSprings are a line of bump stops designed and manufactured by SuperSprings International. They are offered for the Toyota 4Runner, Tacoma, and Tundra, along with many other makes and models. SuperSprings International has offered load-carrying enhancement suspension parts for many different trucks, and SUVs since 1998.
With a platform such as the 4Runner, we have many different options when it comes to building out these rigs. Whether you want to build a badass rock crawler, a full-blown overland build, or just to enhance the ride quality of your daily driver, SuperSprings International has an option for you – and that’s what makes them truly unique.
WHAT ARE SUMOSPRINGS?
SumoSprings are a product line that SuperSprings International offers and are the first load-assisted airless airbags on the market. This doesn't necessarily mean that SumoSprings' sole purpose is for towing though, in fact, the Blue and Black SumoSprings are designed to replace the factory bump stops providing a better, smoother ride all around, for both on-road and off-road applications. They are maintenance-free, do not leak air, and do not require air-lines or compressors. They enhance the load-carrying/towing ability and most importantly for the 4Runner, they reduce and stabilize sway. Overall, they will improve driver control and ride comfort when daily driving, off-road driving, and even rock crawling.
There are two different density options to choose from; Blue and Black. The blue SumoSprings are made of a softer density material, while the black is made of more firm density material. The blue SumoSprings take less weight to compress which results in a softer unloaded and loaded ride. The black SumoSprings have a higher density, meaning there’s more material packed into the same size SumoSpring, which in turn necessitates more applied weight to compress it. This is what gives the black version a higher load rating, but also what creates a stiffer unloaded ride. In most cases, the blue version will apply to most 4Runner drivers on the road.
TIMBREN VS. SUMOSPRINGS
Timbren offers a reliable aftermarket bump stop that I’m sure many of you are familiar with. These bump stops are progressive, which means that the more they compress, the more they resist compression. This is actually what offers a better ride, more so off-road.
The main difference in the SumoSprings is that although they are also a progressive bump stop, they adjust automatically to load or compression. This comes in handy on the trail because this type of bump stop won’t limit your travel as much as the competitors. Also, the SumoSprings provide a much smoother contact patch on the axle. We found them to be noticeably smoother than the Timbrens.
OFFROAD CAPABILITIES
As I mentioned before, these bump stops have a progressive spring rate that adjusts automatically. This means that the patented micro-cellular urethane is continually adapting to how much load is upon it at any given time. This alone is a huge benefit when it comes to offroad applications because you will have more control of your up travel.
If you plan on off-roading your 4Runner, then you should invest in aftermarket bump stops. The bump stops by SumoSprings are a perfect alternative to stock bump stops as they provide the protection you need from harsh bottom-outs all while providing enhanced ride comfort. Even the mild to rough terrain getting to the actual trailhead is going to be much more enjoyable with a set of these.
ONROAD CAPABILITIES
On-road driving with the SumoSprings is just as enjoyable as off-road driving. The highly durable closed-cell microcellular polyurethane material provides a plush ride over bumps and rough roads while providing complete control of the vehicle. When you hit something like a speed bump, the SumoSprings will help soak up the bump, but when you’re doing a lot of cornering, the SumoSprings will help provide rigidity.
If you are going with an overland build, then consider getting some SumoSprings bump stop replacements plus Coil SumoSprings. These inserts are installed into the middle of the coil spring and have a similar purpose as airbags. They will stiffen your suspension, which keeps the 4Runner from handling like a boat when it’s loaded down.
TOWING
If you plan on towing frequently, some kind of spring reinforcement is needed. The reason for this is the 4Runner was not designed to support a ton of weight. Airbags, or in this case airless airbags, are designed to support the weight while towing, which in turn gives you more control. This is a must-have for those long trips while pulling a camper or even short trips towing your boat to the lake.
While towing, these bump stops act as airbags but without the air. This will not only provide a much more enjoyable ride, but your rear-end will no longer sag. If you are looking at towing, you may want to consider the black SumoSprings bump stops. The bump stops we received are the blue SumoSprings. The black SumoSprings are designed to support more weight.
There are many guys who have installed airbags for towing but unlike airbags, SumoSprings are guaranteed to not pop or lose air. If you’ve ever owned airbags, you also know how sketchy it can be working on them. Not to mention, the amount of time an install takes.
If you are looking to increase the stability of your 4Runner while towing heavier applications, you may want to consider getting the Coil SumoSprings as we mentioned above. These won’t support the weight of a trailer, but they will prevent harsh bottom-outs, body roll, nose dive, and more.
INSTALLATION OVERVIEW
TOOLS & MATERIALS
- 13mm Gear Wrench
- New Hardware (provided)
- Blue Loctite (provided)
- Breaker Bar (optional)
- Impact (optional)
The install for the SumoSprings is very straightforward. I took the tire off on one side just to get better pictures, but on the other side (passenger side) I left the tire on and it wasn’t any more diffcult. If you choose not to take the tires off then the only tool you’ll need is a 13mm gear wrench
STEP ONE: REMOVE THE FACTORY BUMP STOPS
After you have parked the vehicle on a hard, level surface and engaged the emergency brake, place blocks in front and behind the wheels to prevent rolling. Observe all safety precautions and wear safety glasses.
Raise the rear of the vehicle allowing the axle to hang freely and rest the frame on the safety jack stands rated for the weight of the vehicle. Removal of the rear wheels is optional. Starting on the driver’s side, unscrew the two bolts and remove the factory bump stop from the underside of the frame.
STEP TWO: ATTACH SUMOSPRINGS TO MOUNTING BRACKET
Attach the mounting bracket to the top of the SumoSprings using the supplied M8 hex bolt and washer after applying a drop of blue thread locker to the threads of the bolt. Use the center of the three holes on the top part of the bracket.
STEP THREE: MOUNT SUMOSPRINGS
Attach the assembly to the underside of the frame using the supplied M8 hex bolts and washers a er applying a drop of blue thread locker to the threads of the bolts. Be sure to position the bracket so that the SumoSprings is o set 1/2” outboard (toward the wheel). Don’t tighten down the bracket all the way just yet.
STEP FOUR: CENTER SUMOSPRINGS ON AXLE
There are slotted holes in the bracket for the bump stops which allow you to move the bracket le or right in order to center the bump stop on the axle. Keep in mind that when the axle flexes, it also rotates forward a little bit with the factory 4-link.
As you can tell in the picture, the previous bump stop was a bit too far forward. With the axle level, place the new bump stop a little bit in front of it and tighten down the hardware. When the axle comes up in this position, it will be centered with the new bump stop.
STEP FIVE: PUT EVERYTHING BACK TOGETHER
If the rear wheels were removed, you can now reinstall them. (Torque wheel nuts to manufacturers spec). Clean up all your tools and call it a day. Before you take it for a spin, ensure emergency brake cables are not touching the SumoSprings. Secure any cables out of the way with zip ties or by re-routing. Ensure all A/C lines, brake cables, and frame are clear of contact or interference.
FINAL THOUGHTS
Overall, we are extremely impressed with the quality of these SumoSprings. We replaced our Timbren bump stops (a very reputable company) with a set of these Blue SumoSprings on the rear of the white 4Runner. The bump stops feel great both on and o the road. I noticed a smoother contact while wheeling around the rocks over the Timbrens. When wheeling with the Timbrens, you can literally feel the bump stop hit the axle – it’s better than stock but the Blue SumoSprings are much smoother.
The thing that stood out to us about SumoSprings is the fact that they have three options available for the 4Runner. No matter what route you go with your 4Runner build, SumoSprings has an option for you.
