The day my car left the showroom, I had it up on the lift for 3 coats of 'corrosion guard' to seal the pores of the Aluminium, as there is so much of it. I'm pretty anal about my cars being as clean underneath as on top, as I show it.<div> </div><div>The one thing that I did give extra attention to was the rear diff frame. The paint on here was incredibly thin, and if you drive your car in anything other than dry conditions, it will end up like the picture above.</div><div> </div><div>Powder coating is possibly the worst idea, it's brittle and comes off in flakes. Take it back to bare metal, spray it with primer and a few odd coats of whatever colour. Once that lot is dry, coat with your chosen corrosion blocker.</div><div> </div><div>Cars, aren't built to last like they once were. You need to get in early to do preventative maintenance BEFORE they fall apart unfortunately.</div><div> </div><div>Don't forget; If you drive your car in winter, spend a good few minutes spraying the underside of the car with the hose to wash off the salt, up and around the wheel arches, pretty much everywhere as it turns cars to dust!</div>