Today I installed some helper springs on my 06 Grand Caravan SXT. I added a Class III hitch and will be fully loaded tomorrow with 5 bikes, 2 inflatable paddle boards, roof bag, and 6 people. We will be loaded to the max, not the first time, but will be the first time with 5 bikes and the hitch. When debating the bike rack and hitch I decided I have to get helper springs for the rear or air bags.

I tried to research to find helper springs that others have installed, but really came up short. Most were adding airbags and I wasn't interested in doing the air bag option.

I did find some generic Leaf Spring helper options, but they all advised against installation with a single leaf like my Grand Caravan. Then I found these generic helper springs from AutoCraft P/N AC121500. Advance Auto Parts Link

I wasn't able to install the springs the generic way as the axle isn't round at the bump stops. And the u-bolt won't even fit around the axle at this location. The u-bolt basically retains the springs when the vehicle flexs through dips diagonally or unloads coming off a bump. I bought hose clamps to do the same job. I also rotated the spring plates and they sit perfectly on the axle and can't slide off front or back. I really like the hose clamps as I can remove the springs in 20 mins if I decided I don't like the unloaded ride with the helper springs.

The top of the spring shifts slightly around the bump stop bumper but stays retained very well by the bump stop. I have driven it through a couple of flex dips and the springs stay retained, but do make noises as they shift around the bump stops. Also the rear is a little bouncier unloaded when driving over small bumps, but much improved body roll for stability.

It looks like a 1-2 inch lift on the rear of the minivan unloaded. I am only posting as I wished I would have found a thread about these when I was looking for helper spring options. I'll update the post in a week with results from the 1200 mile road trip fully laden.



Didn't use the u-bolts as the rear axle isn't round at the bump stops. Rather opted to use hose clamps to retain the springs.



Passenger Side Helper Spring



Passenger Side Helper Spring; close to parking brake cables



Driver Side Helper Spring



Driver Side Helper Spring; close to parking brake cables



Rear view



Looks like 1-2 inch lift in the rear unloaded.

 

Fully loaded about level ride height.

39.5 psi in rear tires.

 

The trip with the bikes was great no problems or bottoming out the rear. Results have been amazing. We have had the springs on the Grand Caravan for almost a year which wasn't the plan, but my wife loves the ride and reduced body roll. I haven't seen any impact to the fuel economy. I installed the springs when I installed the hitch and we have never drug the hitch which was one of my concerns when I put the hitch on. The only thing I need to correct is the headlight aim, they are way too low after the spring install.