Firestone Coil-Rite Air Helper Springs - Rear Axle
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1991 Ford Explorer
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1991 Ford Explorer
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Heavy gear in the back or a loaded trailer can make the rear sag, which throws off your steering, braking, and headlight aim. The Firestone Coil-Rite Air Helper Springs fit inside your existing rear coil springs to keep your ride level when hauling a heavy load. With an adjustable load-leveling capacity of at least 500 lbs?(at most 1,000 lbs), these air springs help maintain even load distribution so your handling and braking stay consistent and controlled.
Every trip is different, so the ability to dial in support matters. With manual inflation valves for each side, you can set anywhere between 5 psi and 35 psi to match how you’re loaded. Add pressure to reduce sag and body roll when towing or carrying uneven cargo, or drop it back down for a smoother ride when empty. Independent side-to-side adjustment makes it easy to level off-center loads for a stable, planted feel on the road.
When bumps and dips hit hard under load, these air springs absorb road shock before it reaches the frame. The extra cushion helps prevent bottoming out and softens contact between the axle and frame so your ride feels more controlled. By keeping weight balanced across both sides, steering stays steady and tires last longer.
Made of durable, elastic polyurethane, each coil insert is built to handle heavy loading and adverse road conditions without cracking or leaking. The kit includes air springs, brackets, hardware, air line, and separate valves for manual inflation. Switches, gauges, compressors, and tanks are sold separately if you want in-cab or onboard control later on. It’s a reliable setup that holds up through repeated use while keeping your suspension working like it should.
The construction material of the fittings may vary.
Customer Satisfaction Score:
97% were satisfied with this product
3% of customers were not satisfied
Ratings & Reviews
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.
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.
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.
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.
Wow what a difference. No more problems bottoming out on rough roads. The installation was a little tough but I can't say enough about the end result. Now I Can pull just about any trailer with the 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.
Easy to install and works as advertised. Keeps the truck level when pulling a trailer with just 10 psi in the device.
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.
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.
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!
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!
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.
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.
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.
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.
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.
The 1/4 in. hose that was supplied is so hard, it's unusable. It's not pliable in any regard and I had to buy new air hose at NAPA. The bags themselves are fine though
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.
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.
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.
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!
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!
Worked well. Second time I’ve installed them on a 4Runner. The result was a needed improvement in sway, dive and sag. It also helps the steering wander.
Firestone airbags have worked well for my 2017 4Runner. When I'm not attached to my camper, I keep the airbags deflated to about 5 PSI. But when I put my trailer 3,500 lb. Onto the back of my 4Runner I get several in of sag. I pump up the airbags to about 20 psi and I level out the whole rig. What a perfect hybrid system to have. It's there when you need it. Perfect system for a sagging. Backside on a rear coil spring 4Runner. Thanks, e-trailer
I bought this set because I was having problems with one of the airbags I previously had gotten. It was on the right side of my forerunner. It had a slow leak. When I replaced the airbag this time it had a very fast leak. I finally found That if I used NAPA Sil-Glyde to insert tube it seems to be holding air. And I squeezed air bag into the spring. Use soap for sliding it in.
Ethan
6/25/2026
I had to take the right rear airbag and deflated it. I took a piece of mudflap about a quarter inch thick and put it on top of the airbag with a hole in the middle of the mudflap piece that gave more clearance between the car and the airbag valve. Now I have had no leaks for a year. With the least 9000 miles of towing and rough terrain.
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Andrew
3/6/2020
Still works well, no issues. Its been a good investment .