Electric Anti-Rust Products

[ggrace]

Guys,

Just put down a deposit on an '05 4.4i Blk/Blk with Sport & Activity - very pumped! It's conditional on being inspected at a BMW dealership tomorrow.

I live in Toronto, ON and the winters are bad and they throw so much salt on the roads. The dealership I bought it from offered to install an electronic anti-rust device for $799CDN. I was hesitant so said I'd let them know tomorrow. Then I called a friend who's a business manager at a BMW Dealership and she said she swears by them and is putting one in her personal car. She also offered to save me $200CDN - which was really nice.

I know this is a detailing sub-forum, but what is the general feeling about this type of product?

Thnx.

p.s. Here's the truck: BMW X5 in THORNHILL, ON - Vehicle Details - AutoTrader

[Weasel]

I understand the principles behind electric rust prevention. I've even used that basic method for rust removal of steel pieces in an alkaline solution with an iron electrode as the sacrificed cathode...But unfortunately it isn't feasible on a vehicle for the simple fact that it is electronically isolated by the tires... The electronic rust protection devices are very real and are used in large ships and some underground piping, but on the ships only the part submersed in seawater (alkaline solution) is protected and the pipes being under ground complete the circuit and offers the protection. Again, the tires isolate you with a vehicle. So unless you figure out a successful way to provide a electron flow for the entire area you want protected it is just an new and inventive way to drain your battery. (like modern BMW's need any help with that!)

Add that to the fact that some of the components most prone to rusting being suspension components isolated by rubber bushings and what are you really protecting that the waxy undercoating stuff doesn't already protect?

But all this said I will say that I have no actual experience with the products as I live in an area that never has snow or road salts, so all comments above are on a physics standpoint and I may stand to be corrected if wrong about any points above.