Dr Music, I see that you did not get a reply from your post. I am wondering what have you done as far as rust proofing your 2017 CX5. Did you end up going to Krown or Corrosion Free ? I have 1 car rust proofed by Krown and 1 by Corrosion free. Corrosion free is less messy and drip a lot less and not as long as Krown. The car with Krown is 2007 and it is excellent shape. The one with Corrosion Free looks good but it is a 2015 and still is relatively new. My 3rd vehicle is a new 2018 Mazda CX-5 GT and I have not decided yet what rust proofing I will go for. It would be nice if you can share your experience since I have some similar concerns with what the rust proofing will do to the added sound insulation on the new CX-5. Thanks. John

 

I bought a new 1976 VW Rabbit and paid $300 for dealer rustproofing. They shot it into the door and fender panels, and I guess underneath. It was warranteed for 3 years. In the third year, the rear fender panels bubbled from internal rust. I made a claim, and found that the rustproofing policy was from a third party company whose certificate said that rust was proof that the rustproofing had not been properly applied. And they were bankrupt.

Nowadays cars are made from zinc galvanized metal that has been immersed in primer and electrostatically painted into every crevice. There is absolutely no need for aftermarket "under coating" or "rust proofing". The purpose and value of rust proofing is in your peace of mind. You will be safe because a modern car will not rust unless a panel is damaged below the galvanic coating. For any lack of rust, you will have your foresight to thank. This is what Corrosion Free and Krown live on.

 

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Hi, please can you give me some tips on rust proofing? I just brought a 2021.5 CX5 Signature Turbo. 2 weeks old and water condensation in rear tail lights.

Which rust proof oil is best?
How has your car held up over x years after rust proofing?
How many years has your car been rust proofed?
Did you apply it yearly?
Is your car free of rust still?
Is it worth rust proofing?
Did your shop do good job rust proofing?
Which shop did you use? Would u recommend them?
I am in Toronto Halton area.
Thanks

 

I have ended up going with Krown in the end and I have been doing it annually. So far I have no problem at all with the Krown and it has no impact on the added sound proofing. My Mazda is a 2015 CX5 GT.