Obtaining Warranty Coverage
This is mostly a general guide, because of the volume of questions I've seen over the years from people stressing out over what impacts warranty, what doesn't, and how to get coverage.
In simple terms, a warranty is when a company legally accepts financial liability for a failure for a specified time period. This doesn't have to be the manufacturer, though it usually is. When someone (a manufacturer, dealer, finance company, etc...) issues a warranty, they are accepting liability for that period of time/distance, accepting that any issues within the warranty coverage areas are either A) not supposed to happen or B) happen infrequently enough that they will be able to cover the cost of the repairs from the warranty charges from others that don't. Legally, it is only A), but practically, it is both.
When something breaks on your car, and it should be covered under warranty, your request for warranty service is legally a request for the warranty issuer to accept liability for damage/repairs as agreed.
If the warranty issuer accepts liability, which is usual, then they reimburse the shop for the costs of repairs. This is true even of dealers. Dealers charge the cost of repairs to Mazda USA, and get reimbursed. They make a lot of money on engine replacements. This is a critical point to keep in mind. The dealers can choose to not even file for warranty coverage (usually due to laziness), or they intentionally or accidentally misrepresent your car and modifications to Mazda USA during the discussion when Mazda is deciding on if they will accept the liability or not.
If a warranty issuer decides they don't want to accept liability, then there is a fight ahead, at some level. Dealers are notorious for making this decision without even asking their parent company. Warranty requests are something of a mark against dealers I think. However, another critical point to recognize is that when a vehicle that is still within warranty period is denied warranty coverage, the warranty issuer has the burden of proof legally. They have to prove that a non-OEM part, a non-approved action, or a lack of required action caused the failure. If your only mod is a short shifter and your visor breaks, they can not possibly prove the link legally, because there isn't any. (Dealers have been known to try crazy stuff like that). If your transmission syncros fail though, well, there is more gray area. Legally, they have to prove the short shifter caused it, but there is enough gray that they might get it by.
Maintenance records is the big one. For all of history of warranties being issued, dealers have asked for maintenance records as proof of service before coverage. However, it isn't actually proof. Records simply close a loophole that they might try to exploit to get out of accepting liability. A vehicle with no service records at all can have an engine failure, and the warranty issues has to prove that a lack of service caused the failure. Legally. Of course getting to that point might still be costly fighting that battle, whether in time, money, and/or stress. They "win" alot of the warranty requests because the owners don't know any better, aren't prepared to fight them, or they are flat out lied to. Talking about all manufacturers here. Mazda is a bit better than most in my opinion, though they are certainly not exempt.
Given the history of failure with this engine, if it got to a legal fight, Mazda has very little chance at winning unless there was something changed about the engine itself (turbo, supercharger, oil, seals, rebuilt, etc...). But you don't want to get to that part. So in the end it comes down to 2 realistic options: 1) Build a relationship with your neighboring dealer, soaking the extra cost of time and money for routine maintenance so you develop that relationship and grease the gears if something warranty pops up, or 2), do everything yourself, and any warranty claims are more casual attempts where you are willing to take it on yourself if denied.
In simple terms, a warranty is when a company legally accepts financial liability for a failure for a specified time period. This doesn't have to be the manufacturer, though it usually is. When someone (a manufacturer, dealer, finance company, etc...) issues a warranty, they are accepting liability for that period of time/distance, accepting that any issues within the warranty coverage areas are either A) not supposed to happen or B) happen infrequently enough that they will be able to cover the cost of the repairs from the warranty charges from others that don't. Legally, it is only A), but practically, it is both.
When something breaks on your car, and it should be covered under warranty, your request for warranty service is legally a request for the warranty issuer to accept liability for damage/repairs as agreed.
If the warranty issuer accepts liability, which is usual, then they reimburse the shop for the costs of repairs. This is true even of dealers. Dealers charge the cost of repairs to Mazda USA, and get reimbursed. They make a lot of money on engine replacements. This is a critical point to keep in mind. The dealers can choose to not even file for warranty coverage (usually due to laziness), or they intentionally or accidentally misrepresent your car and modifications to Mazda USA during the discussion when Mazda is deciding on if they will accept the liability or not.
If a warranty issuer decides they don't want to accept liability, then there is a fight ahead, at some level. Dealers are notorious for making this decision without even asking their parent company. Warranty requests are something of a mark against dealers I think. However, another critical point to recognize is that when a vehicle that is still within warranty period is denied warranty coverage, the warranty issuer has the burden of proof legally. They have to prove that a non-OEM part, a non-approved action, or a lack of required action caused the failure. If your only mod is a short shifter and your visor breaks, they can not possibly prove the link legally, because there isn't any. (Dealers have been known to try crazy stuff like that). If your transmission syncros fail though, well, there is more gray area. Legally, they have to prove the short shifter caused it, but there is enough gray that they might get it by.
Maintenance records is the big one. For all of history of warranties being issued, dealers have asked for maintenance records as proof of service before coverage. However, it isn't actually proof. Records simply close a loophole that they might try to exploit to get out of accepting liability. A vehicle with no service records at all can have an engine failure, and the warranty issues has to prove that a lack of service caused the failure. Legally. Of course getting to that point might still be costly fighting that battle, whether in time, money, and/or stress. They "win" alot of the warranty requests because the owners don't know any better, aren't prepared to fight them, or they are flat out lied to. Talking about all manufacturers here. Mazda is a bit better than most in my opinion, though they are certainly not exempt.
Given the history of failure with this engine, if it got to a legal fight, Mazda has very little chance at winning unless there was something changed about the engine itself (turbo, supercharger, oil, seals, rebuilt, etc...). But you don't want to get to that part. So in the end it comes down to 2 realistic options: 1) Build a relationship with your neighboring dealer, soaking the extra cost of time and money for routine maintenance so you develop that relationship and grease the gears if something warranty pops up, or 2), do everything yourself, and any warranty claims are more casual attempts where you are willing to take it on yourself if denied.