Aluminum trailer, steel coupler; how do I prevent corrosion?

[jelbehai]

Subject pretty much sums it up - I'm putting together an aluminum trailer, and I've figured out how to mechanically attach the frame to the coupler I'm using, but I started worrying about corrosion. I thought about at least using RTV between the steel and the aluminum to keep moisture from making it worse, but maybe that's pointless :confused:

How's it typically handled? Thanks.

[coyote]

I would just paint the AL assuming your bolting the two together...or you can try an anode of magnesium...

[pmurf1]

Why not wrap it in Mil tape? Cheap, easy, and you won't see it once you bolt on the coupler.

[jelbehai]

I am planning on painting the steel (MI salt would destroy it faster than my beard grows). I planned on bolting the coupler "sub-structure" (basically a wedge which would go inside the frame) to the frame.

My concern is the bolts would create an electric connection where they connect to the aluminum frame.

What's Mil tape?

[Old Scout]

http://www.nocorrosion.com/corrosion-control.htm

[BenMara]

http://www.corrosionx.com/

[HalfFastFord]

IIRC, etching primer and mil-spec paint between the steel and aluminum will prevent corrosion.

[CITY WORK]

When we are reinforcing AL rails on semi trailers. We paint the steel reinforcement and put tape over it. Then bolt it to the to the AL rails using rail bolts that have nylon washers that keep the bolt head and the rail separated.

[Sapper]

We use a product called NO-OX that is like a grease that seems to work very well for fighting galvanic action on my junk. Metal bumper and aluminum winch housing and many other things as well.

I also thought that anti-sieze compound would work for this too? Silver though not the koper-kote stuff?

[jelbehai]

Sounds like the trick will be some mil-spec paint, and one of the greases/sprays mentioned above on a semi-regular basis. I'll have to do the same for the axles to the frame too.

Thanks!