The old bag gets new bags

Fortunately for me, Annie has a good sense of humor about post titles like that. Besides, at 2 years old, she knows she is hardly an old bag. But she is a mobile bag, holding us and our traveling needs safe and comfy.

But her rear end was getting a bit saggy with the batteries and water stored back there.
An unladen extended Transit has a 12deg departure angle (at least based on the euro drawing I found. That works out to about 16" ground clearance at the rear bumper.

When Annie gets fully loaded, not only does she slur her words, but her rear is down to about 12" or less clearance. We don't want her dragging her butt on dirty rough logging roads. Really tears up her pants.
So we decided she needed a butt lift. But, her butt should have a variable butt boost. No ifs and, or buts.
We want to normally travel with her rear just a bit down from unladen stock, but for steep transitions, ditches, etc. we want to temporarily raise her butt enough to get her clear.
So, we decided on airbags rather than helper springs.
Additionally, we want to use the bags as a leveling device, which means we want to inflate or deflate each one individually.
Airlift makes a version of their LoadLifter 5000 specifically for the Transit. That seems to be the only one out there specifically designed for our van.
The bags replace the stock jounce bumpers, so we ordered the Ultimate version, which has integral bumpers as a backup if the bags ever spring a leak.
We also got their dual manifold and compressor with wireless remote. That's the way  we'll get individual bag control.

There's not much to say about the installation, the instruction manuals are very good.
But, I should note that there is a potential for drilling the wrong hole size if you just follow the compressor' mounting template. It calls for 1/4"  holes, but that's really if you are not mounting to a closed frame member. DAMHIKT.

We have a trailer hitch with B+ power only when ignition is on, so we are using that as the power source for the airbag system.

Since the manual is very good and Transit specific, I'll only post some picks of the final assemblies.

The compressor and manifold are mounted to the rear of the driver side spring, tucked well out of the way of debris and mud. There was hardly any dirt up there before I started the install.

Here's a mounted airbag

Each bag has a manual fill Shrader valve. Also useful for manually checking pressure, although the remote has a pressure readout. I mounted the valves through the rear bumper plastic shroud, and routed the passenger side lines along and above the hitch.

Right now, fully loaded and with 30# pressure in each bag, Annie's rear is at 15" clearance. At about #60 pounds, I'd guess that about 90% of the rear body weight is on the bags, not the OEM springs. Clearance is about 18" at that point.
We are allowed to inflate to 100#, so it looks good that we'll have a 9-10 " improvement in clearance at the temporary extreme. I haven't had the nerve to drive at that pressure yet. At 50#, the ride gets kind of harsh.

And finally, for something completely different, I got the OBDII Torque Pro app up and running on an old phone.