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Undercarriage it worth it? Help!

Hi Everyone-

My husband is in the military and we are being transferred to Hawaii in July. I was told by a friend that the salty air will cause my car to rust really fast. Would it be worth the price to get the undercarriage procetion? What about getting the current paint chips taken care of? I don’t know what to do.

No don’t bother.

No. If your car is relatively new, then you don’t need to worry about rusting. New cars have technology that protects rust. Also, the undercarriage protection traps in dirt causing rust to accelerate. I live in California about 30 minutes from the beach and no one has it.


I lived on Guam for a couple years, new cars don’t rust there like the old ones did.

Agree, I don’t think you’ll have a problem, but do fix the chips.

When you live in a salty (salt in the air) area like the beach, your car is more likely to rust from top down than from bottom up, like it would if you lived where they use salt on the roads in the winter. Just keep the car washed and waxed and it will be fine.

It is likely less of a problem than your friend thinks. In fact most after factory treatments will actually cause more rust than they prevent. Modern cars have very good rust proofing built in before the built the car. After market treatments can interfere with the original treatments.

Very good advice so far; today’s cars have good factory rust protection. The winter road salt is infinitely worse for your car than the salty air in Hawaii.

As others point out, and I obseverved in the Persian Gulf, cars near the sea will rust from the top down. I would touch up the paint chips, though, and WASH THE CAR FREQUENTLY. I’m sure it will outlast any car in Detroit or Cleveland!

P.S. The tropical sun can raise havoc with your skin. We lived in the tropics for 5 years and my wife went through many bottles of sunscreen and Oil of Olay!

Enjoy your posting in Hawaii!

Sincere thanks to your husband for his service.

Cars today are designed using alloys, electrolytic coatings, conformal coatings, drainage and ventilation techniques, and non-metallic parts specifically for the purpose of preventing the formation of rust. In addition, parts are bonded and where welding is necessary coatings are applied after the welding to prevent rust. Non-metallic fastenings are also commonplace on today’s cars where screws would have been used years ago.

None of this existed long ago. We used to add rustproofing and aftermarket coatings to try to compensate. Before those were avaiable some people used to pour motor oil in cavities to try to prevent rust. None of this is necessary now, and application of it could even compromise the rust prevention the manufacturer built in.

Keep the surface washed, well waxed, and if possible out of the sun. The painted surfaces are really the only areas that need special care in that climate.

Have a great tour.

That’s good to know. When I was there in '72-'73 they rusted almost instantly!