I would powder coat them white. There is a lot of prep I would do to them first like rounding all of the edges. I see electric jack brackets and ladders that have a factory coating and the coating ALWAYS fails at the sharp edges.
Would you do it yourself or take them to a powder coating shop?
I have just gone through the rebuild of the jacks for my Bigfoot, with the Happijac factory's support.
Now, before I assemble the jacks, do I paint, powder coat or use bed liner?
Where I live, the local Rhino and LineX dealers do not recommend bed liner in white. They say set up and flushing is expensive, and that the white liner turns yellow with sun exposure.
If you end up deciding to go with bed liner material, you need to revisit the Line-X approach. Standard white bed liner material can turn a bit pinkish after extended UV exposure. However, if you specify Line-X XTRA, you will easily solve this issue (and it is available in white). Line-X XTRA has UV protectants in the formulation to circumvent fading & color shifts, it offers better gloss retention, and with DuPont KEVLAR, it also provides superior protection against scratches, gouges, and punctures.
I went with Line-X XTRA in black for the bed in my 2007 Dodge Ram 3500, and it looks as new as the day it went in over four years ago.
Good luck with whatever you decide to go with for your jacks.
I'm curious if you coat the extendable part of the jack legs with Line-X will they clear the fixed portion of the jack when you retract them? I have considered having my Happijacs coated with Line-X too.
2009 GMC 25000HD Short Bed 6.0 Gas Engine Crew Cab SLT 4x4
2008 Bigfoot 15C9.5FS
Torklift Talons, Fastguns, Stableload Quick Disconnects, Superhitch & SuperTruss
If I was going to go the direction of having my jacks Line-X'ed, I would only do the outer tube and perhaps the exposed portion of the inner tube & foot that is exposed when the jacks are fully retracted. Happijacs have small "bearing pads" on the lower end of the external tubes which can and do rub on the outer surfaces of the internal tubes during extension and retraction. Over time, this would likely have the effect of scraping and perhaps rubbing off the Line-X coating. For the inner tubes, I would think that powder coating would be a better choice due to the harder and thinner coating involved.