Firestone Coil-Rite Air Helper Springs - Rear Axle
Our Price: $144.12
Confirmed to Fit
1999 Toyota 4Runner
4 Wheel Drive Models
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1999 Toyota 4Runner - Firestone Coil-Rite Air Helper Springs - Rear Axle
- Air Springs
- Rear Axle Suspension Enhancement
- Light Duty
- Firestone
For safety and stability, air springs are the perfect partner for your rear suspension when you are hauling heavy loads. Springs fit inside existing coil springs to help level your Toyota 4Runner, improve braking and handling, and reduce tire wear.
Features:
- Provide extra support for your existing rear coil springs
- Fit inside existing coil spring suspension on your vehicle
- Keep your vehicle level when you are hauling a heavy load
- Improve steering control and balance
- Level your headlight beams
- Reduce tire wear
- Maintain even load distribution with air pressure, leveling off-center loads
- Air bags adjust manually, side to side, with individual inflation valves
- Enable more effective braking and handling
- Work under heavy loading and adverse road conditions
- Increase stability to promote a smoother ride and prevent bottoming out
- Made of durable, elastic polyurethane for years of comfort and stability
- Include all materials necessary for installation
- Brackets, air springs, hardware, air line and separate valves for manual inflation
- Switches and gauges, compressors, and air tanks (sold separately) are available for quick and easy air spring inflation/deflation from inside your vehicle
- Made in the USA
Specs:
- Load-leveling capacity: at least 500 lbs (at most 1,000 lbs)
- Coil-Rite springs will not increase your vehicle's weight-carrying capacity. Do not exceed the manufacturer's recommended weight limit.
- Adjustable air pressure: 5 psi to 35 psi
- Limited lifetime warranty on air springs
- 2-Year limited warranty on hardware
Note: The construction material of the fittings may vary.
Firestone Coil-Rite Air Spring Basics
Firestone Coil-Rite springs fit inside your existing rear coil springs to maximize the effectiveness of your suspension system. The added cushion provided by the air springs allows your vehicle to better handle a heavy load or trailer. Hauling heavy loads or towing a heavy trailer can make the rear of your vehicle sag and the front end rise. This puts more strain on your rear axle and reduces contact between your front tires and the road, causing problems with braking, steering control and traction. By adding air springs to your rear suspension, you can help to level your vehicle for more effective braking and handling under heavy loading or when you encounter adverse road conditions. The air springs also help to level your headlight beams and reduce wear on your tires.
Adjustable Air Pressure
The air pressure in your Coil-Rite springs can be adjusted manually, side to side, to compensate for off-center loads. A centered load improves the stability of your vehicle by reducing body roll. The air springs will also help to absorb road shock and soften contact between your axle and frame. This prevents bottoming out, thus improving ride comfort. Route the air line tubing for the springs to your vehicle's bumper to provide easy access to the manual inflation valves.
Air Spring Construction
Coil-Rite springs are constructed of durable, elastic polyurethane to ensure years of service. Single replacement springs (sold separately) are available for maintenance to an existing Coil-Rite kit.
Air Spring Installation
The Coil-Rite springs install inside your existing coil springs. The custom-fit springs attach to your vehicle's spring seats.
W237604135 Firestone Coil Rite Air Bags - Suspension Kit - Rear Axle
4135
Item # F4135
Installation Details
Customer Satisfaction Score:
97% were satisfied with this product
3% of customers were not satisfied
- Product did not meet expectations
- Wrong item was ordered
- Did not fit
Customer Reviews
Firestone Coil-Rite Air Helper Springs - Rear Axle - F4135
Average Customer Rating: 4.4 out of 5 stars (628 Customer Reviews)
For safety and stability, air springs are the perfect partner for your rear suspension when you are hauling heavy loads. Springs fit inside existing coil springs to help level your vehicle, improve braking and handling, and reduce tire wear.by: Off2Mtns12/13/2017
2016 Toyota 4Runner
Installed on a 2016 4Runner in conjunction with a 1-1/2" Daystar coil spring spacer. Since the coil spacer is hollow, I left one segment of the factory bump stop in place to compensate for and match the height of the spacer. I also added a Firestone T-fitting on the airline for a single inflation point and located the inflation valve next to my trailer plug wiring. Quite a pain to wrestle the coil back in place with the added height of the spacer, but that is no fault of the airbags; pry bar proved critical to wedge the coil back in place since I did not try the bottle jack between the frame and axle trick. After nearly a year, no leaks, bags hold air well. I put 25 psi in them for towing our travel trailer, or keep them at 10 psi for normal running around. I have also found them useful to prevent or at least reduce bottoming out the soft rear suspension that happens when off road driving with even just a couple hundred pounds in the back. Even at 25 psi they ride great and you wouldn't know they are back there at 10 psi. Highly recommend for the low cost and added versatility!
by: Douglas 05/06/2024
2023 Toyota 4Runner
Good option have put on other vehicles in past for hauling trailer. Reduces sag/bounce with boat/RV but can let air down when not towing for better ride.
by: Calvin U08/04/2020
Best $xx.xx I’ve yet spent on trailer towing. They are so great for leveling off vehicle when towing. And they adjust easily for different trailers/tongue weights. Make a “load” of difference and way cheaper / easier than a weight distribution hitch. I installed these myself on a 4Runner, in my garage with two jack stands and a floor jack. Video was great and everything went just as shown in the video. Only difference was that my vehicle has KDSS suspension. Need to tie kdss rod cylinders with zip ties to hold same length when bottom bolts disconnected. Keeps it from needing rebalancing.
by: Nadia09/06/2023
These never worked. There is a defect in the quick connect fittings. When I contacted etrailer they told me to contact Firestone for warranty replacement. Firestone did eventually send me one replacement bag. When I went to have it installed they discovered the second bag also had a quick connect fitting leak. I gave up on the entire hassle of these air bags.
Katrina D.
9/14/2023
It sounds to me like a warranty issue. For Firestone, they prefer to handle all of their own warranties. I will send you their contact information via email.
by: Scott12/10/2017
2017 Toyota 4Runner
Just installed the Firestone air bag system in my 2017 4Runner. After installing a 250lb aftermarket bumper the sag to the springs was just too much, I also tow a watercraft trailer so that would squash the springs even more, the simple solution is the Firestone air bag system. Install was easy. With my spare permamently out of the undercarriage I just used two existing holes to mount the valves. I think for what you get the price is a bit much, but you can look at it like the air bags will provide a service for hopefully years to come, so that is worth the price.
by: Ryan G.05/23/2017
2014 Toyota FJ Cruiser
Install was easy on 2014 FJ Cruiser...pulled the wheels off, jacked it up a bit, and the axle dropped enough to allow room to fit the bags inside the springs. I will see how they perform when I hook up my trailer but they inflate quickly and I can see these will stop my vehicle from squatting when the cargo area and trailer are heavily loaded. Another excellent product offered by etrailer...thanks.
Ryan G.
5/23/2018
After a year of regular use, these bags have been great. They keep my FJ level when towing and as a result steering while towing is vastly better.
by: Tom03/21/2021
2013 Toyota 4Runner
First try at installation did not go well. Put everything up and tried again next day after watching a few online videos. Much better success. Main thing was the instructions did not mention taking the rear wheels off. Once I did that, everything went more smoothly.
by: Dustin06/13/2023
Just got them put on. The instructions in the box were for the wrong vehicle and called for more parts but I looked up a video and turns out etrailer has a really good video that was better than the instructions and showed that the correct parts were in the box.
by: Zachary 04/26/2023
Great product, great service from the e-trailer team.
by: 2014 4runner 08/31/2017
2014 Toyota 4Runner
Works well. Does not leak once installed. Correctly. Is a bit tricky to get hoses cut exactly at 90 degrees (to avoid leaks). On 5th gen 4runner you can just jack up car and install air bags upside down (nipple down). No need to undo axle/shock.
Wraymond P.
8/31/2018
Still working a year later.
by: Mike05/25/2019
2019 Toyota 4Runner
I use them on 5th gen Toyota 4Runner while towing my 19 ft trailer. I inflate them to 30 pounds and my truck is almost perfectly horizontal. No need for the weight distribution hitch which by the way is not recommended on my truck.
by: Nick M03/10/2020
The air bags do a great job of helping to level out the load. The ride seems better as well. Air bags Are not a replacement for a load leveling hitch and should not be treated as such. They can and do complement a load leveling hitch though.
by: Jim D.08/10/2015
1999 Toyota 4Runner
I purchased this product to prevent rear suspension sag in my '99 4Runner while loaded with camping gear and towing a small boat. It's surprisingly easy to install, and it works very well! I'm very pleased with the purchase. And, as always, the customer service at etrailer was second to none! Shipping was fast, pricing was competitive, and the product was exactly as advertised. Thanks to the folks at etrailer!
by: Andrew03/05/2019
Easy to install and works as advertised. Keeps the truck level when pulling a trailer with just 10 psi in the device.
Andrew
3/6/2020
Still works well, no issues. Its been a good investment .
by: Chase M.04/14/2019
2016 Toyota 4Runner
Helps keep our 2016 4Runner level when towing our 3,500 lb travel trailer. Easy to install, very reliable, fill with air using a bike pump. Super simple! Highly recommend.
by: Tanner08/10/2018
etrailer’s website is one of the easiest and best websites to navigate and place an order! They have lots of pictures and how to videos on almost every product I looked at which is super helpful. Their order process was simple. Their order shipping details was very well put together and made it super simple to track my order.
I am extremely impressed with their customer service! We will order everything we may need from this website from here on out!
by: Michael 08/15/2020
2019 Toyota 4Runner
Super easy install didn't even have to take anything apart, just squeeze the bags between the springs. Thank you so much to e-trailer! You guys had this on the shelf and shipped out right away got here early thank you! My only complaint is that your overpriced, but you had it on the shelf so I guess I shouldn't complain. I'm giving you 5 Stars because you are one of few vendors I have dealt with that I had 0 problems with. Worth the expense.
by: Josh 07/29/2020
2015 Toyota 4Runner
Etrailer is our go to for all our trailer accessories. Parts are always delivered on time and they provide quality parts at a great price.
by: David02/25/2021
Not too hard to install between the springs with the rear-end lifted. Currently one side can’t hold more than 35psi probably because of tubing not fully inserted in bag. Will have to lift rear-rear end to investigate...
by: Brett01/21/2019
2015 Toyota 4Runner
Items were missing from the package. I called the manufacturer and they were less than helpful. I purchased this brand partly because of the Lifetime Warranty, however I'm now less than confident that I will have any luck actually filing a claim should any issue arise. If I were to make this purchase again I would go with the competitor's product.
by: DJ06/23/2021
Just installed on a 2020 4runner. Wasn’t as hard as anticipated. I’d suggest using windex and lube the bag up when installing and look up video tutorials on [online] for help. No special tools needed. Haven’t tested it yet but so far so good.
by: Derric09/01/2022
2021 Toyota 4Runner
Quick process great packaging and everything was it good shape
by: Mark 02/06/2021
Mark
2/7/2022
Working great a year after installation. No issues at all.
by: Ed R.10/20/2017
2016 Toyota 4Runner
Having the ability to input vehicle year, make, and model really helps in getting specific product. Very easy to do. Price checked product online with several other websites and it was equal or withing a couple bucks. Free shipping was a plus and excellent packing.
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See what our Experts say about this Firestone Vehicle Suspension
- Recommended Air Springs For A 2023 Toyota 4Runner Out of all the air bags we offer I recommend the Firestone Coil-Rite Air Helper Springs # F4135 for your 2023 Toyota 4Runner. I like the Firestone airbags over the other air bags we carry because they're more durable and are constructed better than the other airbags that we offer. The Firestone springs fit inside the existing coil springs which will help level your Toyota 4Runner. It will also help with improve braking and handling, and also help reduce tire ware. To make you life easier...
view full answer... - How to Remove Air Line From Spring of Firestone # F4135 Coil-Rite Air Helper Springs on 2001 4RunnerIn order to remove the air line from the push connector on the coil air bags, you'll need to use a pair of needle nose pliers and grab the collar on the connector. If you push the collar toward the air bag and pull on the air line at the same time, the line will easily come out of the connector. If you'll be cutting the air lines, Firestone recommends using an air line cutter like # AL10530 to guarantee a clean cut. If the cut is rough, or isn't perfectly perpendicular, the connection...
view full answer...
- Can Firestone Coil-Rite Air Helper Springs be Used on 2019 Toyota 4Runner With KDSSYou can absolutely use the Firestone Coil-Rite Air Helper Springs # F4135 on your 2019 Toyota 4Runner with the Kinetic Dynamic Suspension System (KDSS). This dynamic system will not affect the helper springs because the springs are installed inside the coils of your 4Runner. There are no separate installation instructions for the KDSS version, which has been around for quite some time. I checked the instructions for other vehicles with this system as well as fits to ensure this. I recommend...
view full answer... - Suspension Enhancement Recommendation for 1998 Toyota 4RunnerIn situations like yours you have to go by what the manufacturer of the vehicle states. They are who designed the vehicle and know what is safe to use with it. What you can use is suspension enhancement for the rear axle of your 1998 Toyota 4Runner like the Firestone kit part # F4135 which is a confirmed fit. This will help reduce the rear end sag you are experiencing when towing when you inflate the bags.
view full answer... - Recommended Suspension Enhancements for a 2016 Toyota 4Runner TRDYes, the Timbren Rear Suspension Enhancement System part # TTORSEQ will fit your 2016 Toyota 4Runner TRD. I called my contact at Timbren to confirm this. I also recommend the Timbren 1/2" Spacer For Raised Frame Vehicles part # TA25722-90F00 to offset the lift on the TRD models. The Firestone Coil-Rite Air Helper Springs part # F4135 will also work with your 2016 Toyota 4Runner TRD. The main difference between these and the jounce springs is that they are adjustable which means you can...
view full answer... - Suspension Enhancement Recommendation for 2020 Toyota 4Runner TRDThere are two great options for suspension support that fit your 2020 Toyota 4Runner 4WD with the Timbren kit part # TTORSEQ or the Firestone Coil Rite part # F4135. They each have distinct advantages but I think you'll be happiest with the Firestone. Timbren kits are easiest to install and maintain as they basically install once and you never have to worry about them, but their drawback is that they have a tendency to make the unloaded ride quality rougher. So that's overall why I'd recommend...
view full answer... - Recommended Rear Suspension Enhancement For a 2022 Toyota 4Runner TRD ProThe Firestone Coil-Rite Air Helper Springs # F4135 is the kit that is confirmed to fit the rear suspension on your 2022 Toyota 4Runner TRD Pro with the Fox shock suspension. As this fits into the rear coil springs on your 4Runner there is no need for any spacers. If you off road your 4Runner I recommend going with the SumoSprings Solo Custom Helper Springs # SS68DR. These progressive springs are built with a microcellular urethane that is not as likely to become damaged when off road....
view full answer... - Can A Motorcycle Be Carried On the Back of a 2007 Toyota FJ Cruiser If the weight of your motorcycle and motorcycle carrier is less than the tongue weight capacity for your 2007 Toyota FJ Cruiser then yes, this is feasible. I have personally seen motorcycles being carried on the back of a FJ Cruiser so it is realistic and they do offer trailer hitches and hitch mounted motorcycle carriers so it is also possible. If you don't already have a trailer hitch then the Curt Trailer Hitch Receiver part # 13367 is what I recommend. It sounds like you already...
view full answer... - How Can I Stop my Air Helper Springs From LeakingThe most common issue with air bags like the Firestone Coil-Rite Air Helper Springs part # F4135 is the connection of the air line to the other components. It is recommended to use a spray bottle with soap water to spray each fitting to see which is leaking. Once you have found it remove the air line and re cut it. Make sure to get a very straight even cut. An angled or crooked cut will cause leaking every time. Then place it back in and retest.
view full answer... - How to Reattach a Weight Distribution System to a TrailerThere are a few different weight distribution systems so in order to give you exact instructions I would need to know which system you have. However, the process to reattach the system to a trailer is fairly similar for most of them. If your system uses link chains to connect the spring bars to the frame brackets then in order to reattach the system to the trailer you will need to first install the head and shank back into the trailer hitch. Once the head and shank are in position you...
view full answer... - Could Air Lift Coil Rite Kit for 2016 Toyota 4Runner Install without Removing Coil SpringIf you are able to cut the jounce bumper of your 2016 Toyota 4Runner off while leaving the coil installed on the vehicle you certainly could fit the air bag between the coils to install the # F4135 since this is commonly how it's recommended bag kits like this get installed.
view full answer... - When Should Air Bag Style Suspension Enhancement Have Air Added to the BagsWith air bag kit the best time to inflate them is after the vehicle is loaded. This allows you to inflate the bags to the needed pressure to allow the vehicle to sit as level as possible.
view full answer... - Air Springs And Compressor Recommendation For A 2006 Toyota 4Runner Sport For your 2006 Toyota 4Runer Sprot, I recommend the Firestone Coil-Rite Air Helper Springs # F4135. These springs have a load leveling capacity of at least 500-lbs, and at most 1,000-lbs. It should be noted that the coil springs will not increase your vehicle's carrying capacity, and you should still stay within the manufacturers recommended weight carrying capacity. This system, when paired with the Air Lift WirelessONE Compressor System for Air Helper Springs # AL25980 will allow you...
view full answer... - Will the Firestone Coil-Rite Air Helper Springs # F4135 Fit a 2015 Toyota 4Runner with 2 inch LiftSince you have a 2 inch lift on your 2015 Toyota 4Runner you will need to do adjust the Firestone Coil-Rite Air Helper Springs # F4135 to accommodate the 2 extra inches. You can try cutting the bump stops so that they are 2 inches longer than what the installation instructions call for, but that has not been tested so you wouldn't necessarily know what the weight capacity rating would be. I spoke with my contact at Firestone and he said that he doesn't have any airbags that are fit the...
view full answer... - Suspension Enhancement Options For 1999 Toyota 4RunnerI do have some Firestone Coil-Rite Air Helper Springs # F4135 for your rear axle. If your springs have lost some compression and your rear end feels sloppy, these will help tighten up the back suspension to help especially if you have a trailer connected to your 1999 Toyota 4Runner. If you're bottoming out when hitting bumps/dips in the trails you will want to get the Timbren Active Off-Road Bumpstops # TABSTOR4R for the rear. This will only make a difference if your suspension is being...
view full answer... - Will Firestone Coil-Rite Springs Fit 2010 Toyota FJ Cruiser With Short Leveling LiftYour 2010 Toyota FJ Cruiser with a small, 1-1/2" leveling lift doesn't need the taller coil springs, you can still use the Firestone Coil-Rite Air Helper Springs # F4135.
view full answer... - Suspension Enhancement for 2017 Toyota 4Runner With 2 Inch LiftI checked with Firestone, and spacers are not compatible with their Coil-Rite Springs like part # F4135 that fits your 2017 Toyota 4Runner. There is suspension enhancement you can use however, which is the Timbren Rear Suspension Enhancement System # TTORSEQ. For a 2 in ch lift you would also need a pair of the Timbren 1" Spacer For Raised Frame Vehicles # TA25723-90AD00. I've added links to some video reviews for you to check out as well.
view full answer... - Best Air Springs For 2020 Toyota 4Runner With KDSSThere are coil air springs (though not traditional air bags) that fit your 2020 Toyota 4Runner with KDSS, and the best of those is from Firestone due to their quality. The correct fit for your '20 4Runner is the following: - Firestone Coil-Rite Air Helper Springs - Rear Axle # F4135 The Coil-Rite Springs # F4135 install inside your 4Runner's coil springs, and when you inflate them your springs become more effective, cushioning the load to help level you out, improve stability, and reduce...
view full answer...
- Can Firestone Air Helper Springs Be Used With A Weight Distribution System On A 2016 Toyota 4RunnerIn short, you can absolutely use the Firestone Coil-Rite Air Helper Springs # F4135 which are a confirmed fit for your 2016 Toyota 4Runner with a weight distribution system. With that said, you will more than likely be just fine with just a weight distribution system as it will work to level your 4Runner itself by design. Personally I would go with just a weight distribution first, and if you find that even with a correctly set up weight distribution system the rear of your vehicle is...
view full answer... - Best Suspension Enhancement Option for a 2016 Toyota 4RunnerThe best suspension enhancement system for a 2016 Toyota 4Runner will be between the Firestone Coil-Rite Air Helper Springs part # F4135 and the Timbren Rear Suspension Enhancement System part # TTORSEQ. I recommend the air bags as you can control the level of support/comfort that that you need. That said, if you just want a set and forget sort of deal then the jounce springs are an excellent option.
view full answer... - Recommended Suspension Enhancement for a 2006 4Runner V8 with Suspension Lift KitThe Firestone Coil-Rite Air Helper Springs # F4135 are designed to be used with stock suspension, so it will not fit an aftermarket suspension lift kit, unfortunately. This will also be the same for the Air Lift 1000 Air Helper Springs # AL60809. To install one of the suspension enhancement systems we currently carry for your 2006 Toyota 4Runner, you will need to have the lift kit removed and the stock system reinstalled.
view full answer... - Firestone Coil-Rite Air Helper Springs # F4135 Installation On 2016 Toyota 4RunnerI reached out to my tech contact at Firestone, and he said that as long as there is no pinching or crimping of the air line, you can install the Firestone Coil-Rite Air Helper Springs rightside up or upside down. They will function the same as long as they have the lines running without interference.
view full answer... - Replacement Thermal Sleeve Protectors for Firestone Coil-Rite Air Helper Springs Air LinesFor replacement black line protectors on the Firestone Coil-Rite Air Helper Springs # F4135 you can use the Replacement Thermal Sleeve # F2135820899. The Replacement Thermal Sleeve # F2135820899 states that it is for the Firestone Ride-Rite Air Spring Kits, but both the Ride-Rite and the Coil-Rite use 1/4" line. So the sleeve will also fit on the Coil-Rite air line.
view full answer... - Recommended Suspension Enhancement System For 2004 Toyota 4RunnerI recommend installing the Timbren system # TTORSEQ over the Firestone # F4135. Since you said you occasionally tow or carry a maximum of 3,000-lbs, the Timbren system would be a nice option because you do not have to make any adjustments to the system. As more weight is added to the vehicle either from tongue weight when towing or loading the back of the vehicle, the Timbrens will stiffen to provide more support for the load. Using the Firestone system means you will need to adjust...
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Off2mtns
12/14/2018
Still working great after a year. Knock on wood... no leaks to date. I would consider these essential equipment for towing, and would highly recommend for heavily loaded backcountry travels as well. I did try them near their max pressure on one trip with 5 people, roof top tent, and gear for a week of camping this summer and it was too much and felt very unsafe ped the pressure back to sub-30 psi after driving a few blocks and all was great after that!