I'd never drop 4K on a set of alu coilovers and not cover them. GIS corroded coilovers and have a gander at the results. I've seen springs break from corrosion let alone the damper bodies.
For ex.
Scion tC 1G Suspension & Handling - Ways to revive rusty coilovers? - Does anyone have any solutions on how to remove surface rust from coilovers? My biggest concern is that the coilovers have plenty of rust on the threads. It's preventing me from adjusting the collar/locking nut. I'm looking...
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Here are my covered coils that are at least a decade old by now.
Just pulled them off the car to clean and replace the sad, worn out bump stops.
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After cleaning, I also greased the seals which stay nice and clean from the covers.
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Reassembled, but I forgot to take pics with the covers. They cover the whole threaded boy all the way up to the pillowball. You can see in the second pic the corrosion on the top of the pillowball (spherical joint) yet the lower side is corrosion free due to the cover's passive protection. I ofc cleaned and greased the pillowballs with some military grease, real hard to push out.
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