Will the Firestone Coil-Rite Air Helper Springs # F4135 Fit a 2015 Toyota 4Runner with 2 inch Lift

Question:

I have a 2015 4Runner and I want to get the Firestone Coil-Rite Air Helper Springs - Rear Axle. The issue is that I have an aftermarket 2 inch coil Toytec 2 inch Lift for the 4Runner TRD Pro and I was wondering if this will fit a 2 inch taller spring or if I need a different airbag? The inner diameter is the same between the stock springs and my new springs. I measure both at 5.25 inches. I measure the height of the brew springs in my unloaded vehicle at 11.25 inches between the lower and upper perches of the spring. I was wondering if I would be able to buy the air helper spring for the stock and only trim the bump stop about 2" longer than the instructions? Thank you!

asked by: Carl R

Expert Reply:

Since 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 measurements that you took of your new springs. The closest that is available is the Replacement Air Spring # F6003 which fits the same diameter as the air springs in the kit # F4135 for your OEM springs. The height of springs that this Air Spring fits is 10 inches.

My contact said that it would be more cost effective to just purchase the kit # F4135 and then replace the air springs themselves. Piecing a kit together will end up costing a bit more.

You may also want to consider installing a compressor kit like the Firestone Air Command II # F2178 which will allow you to adjust your Air Springs no matter where you are.