This week we built a prototype airbag lift for the rear suspension. Our ambulance does not have leaf springs. It came with an air suspension system (Link Ultraride). We couldn’t find any off the shelf lift kits that would work with this system.
Background:
The goal is to clear 40″ tires and limp home if an airbag fails. Adding some type of spacer under the airbag, along with cutting the fender and wheel-well, will allow us to accomplish this goal. We were planning a 2.5″ lift for the front and wanted something similar to this height in the back.
We couldn’t find any steel or aluminum disks that were large enough (and cheap enough). Then I happened to find some rubber patio pavers at the HomeDepot and thought they might just work. Rubber and polyurethane spacers are commonly used in suspension systems and the price was right, only $30 bucks for 6.
The prototype:
We chose to use 3 pavers under each airbag for a lift height of 2.25″. Here are the main steps:
- Super glue the pavers together
- Trace the air spring adapter plate on the paver
- Cut the paver along the trace line (we used a jig saw with a long coarse blade)
- Drill holes in the paver for the adapter plate bolts (we needed longer grade 8 bolts)
- Optional but recommended: Extend heatshield
- Optional but recommended: Longer rear shocks
- Optional: Extended bump stops
The image below shows the Airbag, adapter plate, and the cut out pavers for one side.
The image below shows the extended heat shield. We just used some scrap aluminum from the ambulance, cut it to size with some electric shears, then bolted it to the existing heatshield. Round any sharp edges so that you dont cut your airbag if it comes into contact. You can also see the airbag, adapter plate and pavers bolted in place. We found some longer grade 8 nuts and bolts at the hardware store. We also used a nylon lock nut to make sure the bolt does not come loose and fall off.
The image below shows the longer bump stops. We used a 5″ bump stop for a jeep and some 6″ 7/16 bolts to extend the bump stop.
We still have to cutout the fenders and lift the front before we can test it out. If you decide to do something similar, do so at your own risk, as this has not been tested. I will update this post once we have some miles on it.
