Hey guys, I was under the JK today changing the oil and noticed that the rear driveshaft had some surface rust on it. While I know that the driveshaft is a pretty beefy piece of steel and wont rust through anytime soon, especially since they dont salt the roads very often here in NC, I still want to keep everything lookin purdy
So the question: Has anybody else painted their driveshaft? And if not, is there any reason not to do it?

 

Don't worry about that surface rust on the stock drive shafts. It's designed to do that. There's some technical mumbo-jumbo behind it, but basically that thin layer of rust protects the shaft from further corrosion.

 

I don't like rust on my stuff, either. I painted mine.

 

The process you describe is used on many items. One very obvious one is on new bridge construction.
Is this process used on our driveshafts? Only a call to a Chrysler engineer can answer that for sure.

 

It would take around 6000 years for your driveshaft to rust to a point it is useless. Rust itself ends up protecting the very metal its coating.

 

Tell that to those peoples' families who perished and were injured in that bridge collapse in Minnesota. That was from rust fatigue. I just don't buy it. At least not for everything.

 

I don't know the details of any bridge collapse incidents, therefore I cannot make a comparison.
However, when asked why a new bridge accross the local river was not painted, and in fact appeared to be rusting, an engineer involved with the project said it was part of the plan to prevent catastrophic corrosion. It is related to the type of steel used.
When you blue or brown a rifle barrel, you are forcing a thin layer of corrosion (one of the various iron oxides) to form.
Stainless steel (the bright kind) is protected from visible corrosion because of a microscopic layer of oxidation which forms on the surface. When scratched, the newly exposed stainless steel very rapidly forms a new microscopic layer of oxidation before visible oxidation can form.
Yes, in some cases, corrosion is used to "protect" from corrosion.

 

wow ,i will never look at rust the same

 

Most of the time, though, corrosion is bad. I doubt it is used to protect the driveshaft (the original topic). Only the designer can answer that question for sure.
There is no downside to an even coat of paint on the driveshaft, in my opinion.

 

A nice coat of rustoleum either sprayed or brushed would do wonders for the appearance of your driveshafts. I'd love to do mine but my rusty jointswon't let me get underneath the blasted thing for now