Just came from an inspection of my car with my dealership's manager, Rico (Mid City Mazda in Sudbury ON). As expected, he believes that all my bubbling is due to stone chips. To prove this, he pressed down on some of the blisters and they were very hard. If they had had underlying rust, they would have been very soft and much larger. He did state that the body shop will sand those down (the ones on flat panels like my doors, roof, rear liftgate). If there is any rust beneath, they will know immediately that it is sheet metal corrosion and not rock chips and take it from there.
This assertion of "stone chips" is supported by the fact that almost all the blisters are on my side sills and lower portion of my doors, where you would expect rocks to hit the car. So, it IS possible but we'll know for sure when they check the blisters. They will **** open up the doors to verify that there is no rusting within which could be causing the surface bubbling.
Plan is to sandblast and refinish the entire rear quarter panels, both rear bumper seams (removing part of the bumper), and the bottom trim of my rear passenger doors. In other words, all the obvious rust patches. Once those are done and refinished, they will put 3M protective tape over the areas to ensure further stone damage does not occur. Both side sills will be entirely coated with 3M since they have to remove those anyways, to get at the lower door trim. They'll even put the tape on the inside of the wheel wells (what a job!) He wasn't sure if Mazda Canada would ok that but did tell me that the dealership itself would cover the cost. So, no funds from my end!
As for the rear doors, they will "blend in" the new paint from the quarter panels to ensure that the whole car's paint looks right. They'll get the blisters on the back doors via this process. All other blisters on the flat panels will be sanded down and refinished. As Rico (dealership manager) said, you don't want to start repainting entire panels unless absolutely necessary since that will negatively impact resale value. For now, since they believe it is all superficial damage, they'll take care of the blisters one by one.
The blisters inside the bottom of the door jambs they will cover with 3M to prevent rusting. They are so tiny that just keeping them as is would be sufficient. Again, the less painting, the better for me and the value of my car! I did ask about "what if these areas really do rust or if the bubbling restarts?" Rico said that there is a 1 year warranty on repair work (typical for any rust repairs done at any body shop) so we just need to keep a close eye on the situation. Again, if they start to do the work and find out that there is rust beneath the blisters, that will be a whole different scenario.
Lastly, I will be given a loaner car at no cost to me by the dealership. I'm booked for next Tuesday at the body shop so will drop the car off at the dealership and they'll handle things from there. They think it will take 2 days but if longer, I can keep the loaner as long as the job takes. Fabulous news since the job won't be rushed and I don't have to worry about the rental cost!
At least I know that if this does turn out to be metal corrosion, we'll deal with it. For now the determination is surface damage which will be handled by refinishing the back of the car entirely and removing the blisters individually. I really didn't want the entire car repainted as that would drop the resale value dramatically! Hopefully he's right and this will be the perfect fix. Adding 3M to the wheel wells, area around these, entire side sills, and lower door jambs will address all the areas highly susceptible to stone chip damage....
I'm not entirely convinced that this really IS rock chip damage since I'm not a specialist and can't tell myself if bubbles are internally based or externally caused. For now, I'm willing to try this "quick" fix and see how my car holds up until next year, especially considering that the work is being done entirely via goodwill, including providing me with a Mazda loaner car. Believe me, I'll be watching very closely for any more bubbling or recurrence of rust and will be into the dealership immediately.
Last thing. My dealership manager again restated that these cases are being handled individually by each dealership. They need to do a visual inspection. That coupled with your service history will determine whether or not you get covered under warranty, goodwill, or not at all. Point is, each one of you must go in to your dealership. Speak to the Service Manager AND the owner/manager of the dealership, if needed. If that doesn't pan out, ask to meet with the District Service Manager whenever he/she is in town since they make the final decision on warranty issues. Last step would be to call Mazda Canada directly.
So, for now, good resolution to my complaint since I'm not paying for any of the costs. Again, I'm not really sure if this fix will be what my car needs in the long run but I have a year under repair warranty. If OTHER areas bubble/rust, my dealership assured me that they will cover those repairs too due to my excellent service history with them (and they know that my car is very well maintained).