Do not know about leaf springs, would guess (WAG) that they would be lower stressed then coil springs.
I'm working on design at work presently where we are designing tiny leaf springs to hold test tubes (vacutainers)....pretty much the same issues as coil spring design, as you drive the rate lower, the stress increases. The math for leaf springs is the same as beams, either cantilevered or simply supported.
powder coating would imply removing them? Why not just wire brush off the scale and spray them with Eastwood rust encapsulator and then follow with black spray paint or their chassis black.
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2005 E350 RB 6.0 PSD for extended fun
1989 Landcruiser FJ62 for local fun
2011 VW TDI Golf for hwy fun
I would take them apart, media blasted then simply spray painted with epoxy and then reassemble it and installed you might have to do this every couple of years but it would be inexpensive and relatively easy.
The reason I would go the inexpensive route is because they flex so much. An expensive coating might not be able to keep up with the flexibility and peel or flake off after time. Once you remove the rust by media blasting them and sealing them up with an epoxy paint I doubt they would rust quickly unless the paint was broken where moisture could get in.
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Rob.
Current:
2001 E350 PSD w/ a bunch of stuff.
And had three other E350s...
The folks at Ken Imler Diesel(big diesel shop in Sacramento) are recommending replacing my leaf springs because of rust. Can the rust be treated with one of the suggestions here or is it just better in the long run to replace them?
James
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Sacramento, Ca
'06 E-350 RB-50 6.0 PSD 4x4
Agreed. Every vehicle up here (Alberta) looks like that after a year or two. Rusty leaf springs aren't really a concern IMHO. More of an annoyance if they start squeaking.