Firestone Coil Rite Air Helper Springs for a 2025 Toyota Sienna

Updated 08/11/2026 | Published 08/05/2026

Question:

Looking for airbag kit for 2025, Toyota Sienna, with no compressor just the hoses and Schrader valve and hardware.Can you refer me to the part number and on on your website

asked by: Carlos P

Expert Reply:

Hi Carlos,

For your 2025 Toyota Sienna you need The Firestone Coil Rite Air Helper Springs, part # F4155. These are the only air bags we carry for your Sienna, and you do not need a compressor. The kit includes the air springs, air lines, Schrader style inflation valves, and the hardware needed for installation, so you can simply adjust the pressure manually when your load changes.

These fit inside the rear coil springs and give you up to 1,000 pounds of load leveling support with adjustable pressure from 5 to 35 psi. They’re a nice option when the back of the Sienna is squatting from passengers, cargo, or the tongue weight of a trailer because you can add just enough air to help bring the suspension back where it belongs. They won’t increase the Sienna’s factory carrying or towing capacity, but they can make a noticeable difference in how the suspension handles the weight you’re already carrying.

If you’re getting rear sag specifically while towing, I’d also want to look at the trailer setup since a weight distribution system could help. What are you noticing with the Sienna right now, rear end sag while towing or when it’s loaded down with passengers and cargo?

expert reply by: Heather A

Jason H.

8/9/2026

These air bags have helped support heavy loads for our 2021 Sienna. We mounted the valve conveniently and discreetly under the back bumper. Beware that the elbow off the bottom of the bag has very low ground clearance and a slightly tighter elbow and small shield helped resolve this issue. It’s not perfect but we found no other solution for the Sienna. We routinely have a full car with adventure gear and a 4 bike hitch rack attached.

Michael

8/9/2026

For my 2025 Sienna I have the Firestone Coil Rite Air Helper Springs, part # F4155. Are you planning on installing them yourself? They aren't hard but you do need to remove the rubber bump-stop. I also had to drill a hole on the lower part for the hose as I didn't have the tools to disassemble the spring itself.

Tom

8/11/2026

I can’t get them to hold full air pressure more than a day. My mechanic can’t either. I’d go with Sumo springs instead. No leaking. Mechanic said they were a pain to install. I’ve used another brand of airbag before. It failed on the first trip. I must always carry a pump to keep pressure up. If it gets too low, the manual says they could be damaged.