Seeking Information on OME/Ironman/Dobinsons Springs for BJ70

[LDowney]

Since all feedback on OME, Ironman, Dobinsons and Terrain Tamer was all positive, my selection came down to cost and availability. The local 4 Wheel Parts outlet priced all the parts needed $200-300 less, so they carried the day. I should note that 4 Wheel Parts offered free shipping to their store which was a significant part of their cost saving.

For the Front Springs, I selected the CS006F springs paired with 60009 Nitrocharger Sport shocks. These springs are rated at 51 to 110 Kg (112 to 242 lbs) in constant load above stock. These springs came with a surprise "+" and "-" differentiation. The + springs are reported to be slight higher stiffness than nominal and the - being slightly less stiff. Therefore, I installed the + spring on the driver side.

Also, the steering dampener was replaced with the OME OMESD24.

For the Rear Springs, I selected the CS004RA & RB springs paired again with the 60062 Nitrocharger Sport shocks. These springs are rated at 200Kg (440 lbs) in constant load above stock. The RA springs were reported to be slightly stiffer than the RB. With the spare tire and CO2 tank adding more load to the right rear, I installed the RA spring on the right side.

Installation/fitment was spot on. The truck sits very close to level empty. Test drives have been very good. No driveline vibration even going down the interstate at +70 mph. Also, the ride quality has been very smooth and soft. I was expecting the ride to be stiffer (even harsh) with the heavy duty springs.

I do have a concern. The rear shackles have already moved ~30-40 degrees past vertical. This indicates that the spring have flattened out some with the truck in an unloaded condition (the fuel tank is full). I will have to watch this to see if it continues to progress. I certainly don't want the springs to be mostly flattened out before I add a full load of tools/parts/gear for a trip.

Because my words never do justice to what I am seeing and describing, here are a few pictures.

 

[crikeymike]

I do have a concern. The rear shackles have already moved ~30-40 degrees past vertical. This indicates that the spring have flattened out some with the truck in an unloaded condition (the fuel tank is full). I will have to watch this to see if it continues to progress. I certainly don't want the springs to be mostly flattened out before I add a full load of tools/parts/gear for a trip.

How are they now? Looks like you may need an extra leaf back there. That shackle angle in the pics is not bad, and the truck will ride better with that geometry. But after adding a full load to the back, they definitely could have squished down some more.

FYI, Dobinsons will be stocking springs and full suspensions in the USA, to make them more available for the 70's, and cutting the delivery times drastically.

 

[LDowney]

How are they now? Looks like you may need an extra leaf back there. That shackle angle in the pics is not bad, and the truck will ride better with that geometry. But after adding a full load to the back, they definitely could have squished down some more.

FYI, Dobinsons will be stocking springs and full suspensions in the USA, to make them more available for the 70's, and cutting the delivery times drastically.

Sir,
The rear springs sagged much more over the next two months. In March, I had the opportunity to test it offroad with just me and a passenger for load and the springs sagged more to the point where the shackles had rotated hard against the frame. At this point, there was no doubt that the rear springs were unacceptable and it was obvious to demonstrate.
So I contacted ARB and shared all the details. It took a few weeks for my request (case) to reach the ARB Tech Department for follow-up, but the ARB team engaged and resolved the situation. ARB sent me replacement rear springs with two extra leaves which I added to the springs before installing them. They have been on the 70 since ~June and have showed no signs of sagging, plus the ride seems to be comparable to the first set of springs (i.e., not noticeably stiffer).

Very happy camper now with my ARB suspension. I probably should have shared these details earlier for community information. Thanks for the question/reminder.