Air Springs for the Truck

I have been using a load distribution to transfer some of the load from the rear axle of the truck to the front axle of the truck and to the trailer axles.

Because of the size of my trailer I ended up with a massive hitch.  The part that gets attached to the truck weighs 70 lbs and is awkward to carry.  The two bars that act as springs exert about 500 lb each onto the trailer frame.  They bent the brackets that carry them and are slowly cutting through them.  I knew early on that this was not a permanent solution.

Hitch for 3800 lb GVWR r-pod on the left.  Hitch for 8800 lb GVWR Cougar on the right 

I looked around for other options and settled on air bags for the truck.  Whereas some smaller trucks have different towing capacities with or without a load distribution hitch, my truck has a rated tongue load of 2000 lb either way.  The trailer has a 1400 lb tongue load with a full fresh water tank.  Using truck scales I determined that the distribution hitch I was using only put about 200 lbs back on the front axle (from 4600 lb to 4800 lb). 

Given all of these factors I decided to try using air springs on the truck as a way to level the load and improve handling.  I installed them while we were in Port Townsend and after one test drive was amazed how much better the truck drove than with the load distribution hitch.

The air springs make the rear axle suspension stiffer so not only do they raise the ride height but they reduced the bouncing that occurs when you go over a bump.

There are still a few related upgraded I have in store.  I have an onboard compressor that I have not installed yet.  This will allow me to adjust the pressure more easily and provide a more convenient way to maintain correct pressure in all 10 of my tires (2 spares).  I also need to replace the massive 70 lb hitch with a much smaller, adjustable one.  That way I can level both the truck and the trailer (see below).

The air springs get installed where the jounce springs used to be.

Passenger (right) side air spring

Driver (left) side air spring

Air lines are routed to the rear bumper.  Schrader valve for manual inflation.

The pictures below show the difference the air bags make.  With 5 psi the rear of the trailer is about 2 inches higher than the front.  It doesn't look dramatic, but the difference in ride quality was striking.

With 5 psi in the air springs.

The trailer is level with 20 psi, but the truck still sags a bit.  A smaller, lighter, adjustable height hitch will solve this issue.

With 20 psi in the air springs.