DIY Engine oil change and Manufacturer Warranty

Hello guys,
Does anyone have any experience with this subject, and how problematic can it be?
Before doing it I emailed my dealer to confirm that I would not have any problem with the warranty in the future if I do it myself.
The dealer's answer was vague and undefined. He basically wrote me that, if something happens with the engine then the warranty will be voided. But he did not specify - something happens during the oil change procedure or in general in the future.
I requested more specifics on his answer, but haven't received any response.
Nevertheless, I went to Mazda's dealership and purchased 5 quarts of the moly oil along with the OEM filter. The parts salesperson was 100% sure that if I keep all slips and invoices, then my warranty would never be voided. He also mentioned that the first oil change at the dealership is always for free, but I still couldn't sacrifice the pleasure of changing it myself :)
In my personal opinion, this is not about the dealership's decision to accept or void my warranty. There should be some kind of Mazda's policy in the US regarding this particular subject, and based on this policy I can demand my warranty in the future.
I personally have zero experience with it and thought maybe more knowledgeable and experienced members of this forum could shed some light on this subject.
Thanks in advance!
 
Hello guys,
Does anyone have any experience with this subject, and how problematic can it be?
Before doing it I emailed my dealer to confirm that I would not have any problem with the warranty in the future if I do it myself.
The dealer's answer was vague and undefined. He basically wrote me that, if something happens with the engine then the warranty will be voided. But he did not specify - something happens during the oil change procedure or in general in the future.
I requested more specifics on his answer, but haven't received any response.
Nevertheless, I went to Mazda's dealership and purchased 5 quarts of the moly oil along with the OEM filter. The parts salesperson was 100% sure that if I keep all slips and invoices, then my warranty would never be voided. He also mentioned that the first oil change at the dealership is always for free, but I still couldn't sacrifice the pleasure of changing it myself :)
In my personal opinion, this is not about the dealership's decision to accept or void my warranty. There should be some kind of Mazda's policy in the US regarding this particular subject, and based on this policy I can demand my warranty in the future.
I personally have zero experience with it and thought maybe more knowledgeable and experienced members of this forum could shed some light on this subject.
Thanks in advance!
Dealer will never put anything in writing for liability purposes in case you ruin the car due to your own ineptness.

Trust the part's guy.

If you change the oil, and dont tighten the filter or drain plug securely and all your oil drains out and you blow the engine, then no it won't be covered.

However if you DIY and a rocker arm fails or the cylinder head cracks from a defect then yes it will be covered under warranty during the warranty period. Just keep all reciepts for filter, oil, etc and keep a car log of all dates for oil changes, etc. I also have my oil tested and get a UOA report that i keep with the log.
 
as long as you keep receipts and log records you would be ok. And if you buy oem oil and filters even better or at least the oem oil filter.
I had a warranty claim and they wanted to see ehat oil filter I used. Only then they sent the claim and had the warranty repair. It was repair for oil control valve.
No questions about the oil but as long as its the correct one and then change is done on time its ok for DYI.
And yes there is a policy its in the car manual. Mazda North America allows that.
dont forget to get new o-ring for the oil plug when changing the oil.
 
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... There should be some kind of Mazda's policy in the US regarding this particular subject,...
My owner's manual does mention non-Mazda maintenance, including "self" (i.e.DIY) maintenance. That write-up basically says the same things that everyone has already posted, relative to keeping receipts and dated records of oil changes and any other work, along with using only materials which meet Mazda specifications. So take a look at the maintenance section in your manual, and I think you'll find what you've been looking for.

And on the subject of the Mazda filters, be advised (if you're not already aware) that they sell 2 flavors of the filter - the regular one, and also what they call a "value" filter, which has MV marked on it. If they sold you the MV filters, and you're not familiar with this subject, you might want to search and find the threads which discuss these MV filters. Then, after reading what's been written about them, you can make your own decision about using them or not.
 
"dont forget to get new o-ring for the oil plug when changing the oil."


The drain plug uses a crush washer.
 
Thank you guys,
I already did it two months ago, but after reading those reports regarding the cracked cylinder head I have become more concerned about the warranty.
This forum is a great source of information, where I found everything I needed to know. I went with the Thailand OEM filter, Mazda's moly oil, and OEM aluminum washer.
The part sale guy also mentioned about the Carfax report. Normally, the dealer shares the maintenance record with them, but in the case of DIY oil change, some questions may potentially arise when you trade the car.
I checked the Carfax and there is an option to keep all maintenance records for DIYers, even with a photo-upload of all receipts. I don't know how important it is, but as an option - why not.
 
***YMMV***

This was my recent personal experience.

I DIY'ed since new off the lot.
Engine needed warranty work.
First thing I was asked was my maintenance records.
I provided my own records (date/mileage), receipts for oil, OEM filter & gasket.
No further questions and repair was approved.
 
As long as you keep the receipt for filters and oil you are good to go.

You do not have to use Mazda branded parts.

In order to deny warranty Mazda have to proof that the oil or filter is not up to the specification,
and that they are a direct cause of the failure.
 
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Write the date and mileage at the time of the oil change on the parts receipt. That saved me on an OEM battery I bought at the parts counter that went bad
On a previous car, saved receipts got me a free replacement AC Delco alternator after 4 years and a free Moog tie rod end after 5 years at one parts store because they were lifetime warranty parts and those parts were rather pricey. And at O'Reilly Auto parts I got a free drivers side power window switch after 1 year. The guy there said it was good I had the receipt because "it was never entered " , whatever that exactly meant because they should have had a record of the transaction in the computer. Caveat Emptor.
 
When I do an oil change to record the mileage i take a time stamped photo of the mileage on the speedometer with my cell phone and print out a copy to go with the receipts for the filter and oil.
 
When I do an oil change to record the mileage i take a time stamped photo of the mileage on the speedometer with my cell phone and print out a copy to go with the receipts for the filter and oil.
Actually, the photo that you described doesn't provide anything extra to writing the date and mileage on a receipt, the way most of us do. None of these things proves that the oil change was done on that date and mileage, or even done at all for that matter. It would take something like a timestamped oil change video, or at least a timestamped photo of the underside, showing the filter and drain plug removed from the vehicle (along with the mileage photo), as absolute proof that the work was done as indicated by the records.

I'm not writing this to be snippy, or critical of what you're doing, just trying to point out that it's not giving you anything extra from a legal perspective. And I'm also not saying that another photo or the video is necessary or should be taken; because I can't recall anyone ever reporting that their oil change maintenance history was rejected by a dealership saying that the work shown on the records was actually not done as indicated by the doc. But by all means, do whatever makes you happy.
 
Actually, the photo that you described doesn't provide anything extra to writing the date and mileage on a receipt, the way most of us do. None of these things proves that the oil change was done on that date and mileage, or even done at all for that matter. It would take something like a timestamped oil change video, or at least a timestamped photo of the underside, showing the filter and drain plug removed from the vehicle (along with the mileage photo), as absolute proof that the work was done as indicated by the records.

I'm not writing this to be snippy, or critical of what you're doing, just trying to point out that it's not giving you anything extra from a legal perspective. And I'm also not saying that another photo or the video is necessary or should be taken; because I can't recall anyone ever reporting that their oil change maintenance history was rejected by a dealership saying that the work shown on the records was actually not done as indicated by the doc. But by all means, do whatever makes you happy.
For me, especially with the problems the engines potentially have, the best documentation for me is the UOA reports. Will possibly diagnose any problems and also serves as proof of oil change
 
For me, especially with the problems the engines potentially have, the best documentation for me is the UOA reports. Will possibly diagnose any problems and also serves as proof of oil change
Sorry, but the UOA alone doesn't legally prove anything about oil changes, unless there is video/photos to go along with it. You send them a small sample of oil, but that sample could have been taken by just cracking open the drain plug to let a bit dribble out, without ever changing the oil at all. Or the sample might not even have come from that vehicle at all. I'm talking legally here, and not what most everyone believes to be reasonably true.

Again, I'm going to continue just writing date/mileage on a receipt, but have no problem with anyone doing more than that, or keeping their records by another method.
 
Sorry, but the UOA alone doesn't legally prove anything about oil changes, unless there is video/photos to go along with it. You send them a small sample of oil, but that sample could have been taken by just cracking open the drain plug to let a bit dribble out, without ever changing the oil at all. Or the sample might not even have come from that vehicle at all. I'm talking legally here, and not what most everyone believes to be reasonably true.

Again, I'm going to continue just writing date/mileage on a receipt, but have no problem with anyone doing more than that, or keeping their records by another method.
Yeah I guess legally only a receipt/invoice from the dealer or mechanic . But ya know, if you think about it, they could just switch the oil and not change the filter. If it gets to the point where the head cracks and a manufacturer says it was due to lack of maintenance because your DIY receipts aren't proof enough then the country(and world) is in even worse shape than previously thought. Then it's off to court and lawyers fees to prove it was a defect. But most people that are too lazy(or cheap) to change the oil are usually too lazy(or cheap) to spend the time/money to buy oil, filters and UOA analysis.
 
On a previous car, saved receipts got me a free replacement AC Delco alternator after 4 years and a free Moog tie rod end after 5 years at one parts store because they were lifetime warranty parts and those parts were rather pricey. And at O'Reilly Auto parts I got a free drivers side power window switch after 1 year. The guy there said it was good I had the receipt because "it was never entered " , whatever that exactly meant because they should have had a record of the transaction in the computer. Caveat Emptor.
Just thought of something and want to list another reason to save that receipt, and that being the warranty period for that part you bought may have gotten shortened since you bought it and that new (shortened) period will be shown in the computer while your receipt should show the longer warranty duration when you purchased it.
Although it didn't affect me because I kept the receipt, sometime after my alternator replacement I bought a starter and found that the AC Delco reman warranty had been shortened to 2 years ( contrary to lifetime warranty I mentioned in my post above I think it was 5 years -- but that didn't affect things).
But anyway, I could see where warranty is denied because of a new shorter warranty period shown in the computer and lacking a receipt, there is no record of the longer warranty period at time of purchase. Thought this 'twist' was worth a mention.
 
I guess it really depends on what your risk tolerance is as most dealerships will typically try to deny warranty work as much as possible. It's definitely much more expensive at around $80 per oil change at the dealer versus DIY which is around $40, especially if you are purchasing the engine oil from Costco or somewhere cheaper and then getting the oil pan gasket/oil filter as well. In my opinion, I would DIY when the warranty period (5 years/60,000 miles) is over since the dealership keeps service records of the vehicle automatically and any claims that you "broke the vehicle" during the ownership of the vehicle can easily be refuted if this issue ever arises.

Looking at the 2023 CX-5 owners manual, Mazda recommends changing the oil/filter at 7,500 miles (Schedule 1 for U.S. and Puerto Rico) and I know that most people are religious about 5,000 mile oil changes but the below table shows the price savings that I calculated based on either a 5,000 or 7,500 mile oil change interval based on the average price of an oil change from my experience. I normally opt for the 7,500 mile oil change interval as I think 5,000 is a bit overkill for my liking since most of the engine oils nowadays are full synthetic. In addition, more money would be saved by extending the oil changes a little longer but it would really depend on personal preference as there's no wrong answer here.

To conclude, I guess it depends if you would rather save a few hundred bucks for an oil change over the warranty period of the vehicle and have the dealer fight tooth and nail to prove that something was broken during your ownership of the vehicle versus eating that cost and knowing that the onus is on the dealer if SHTF. Reading through the other posts, it seems like there's not a definite answer here but everyone makes a valid point.

5,000 Mile Change Interval
#MilesDIY ($)Dealer ($)Price Difference ($)
15,000408040
210,0008016080
315,000120240120
420,000160320160
525,000200400200
630,000240480240
735,000280560280
840,000320640320
945,000360720360
1050,000400800400
1155,000440880440
1260,000480960480

7,500 Mile Change Interval
#MilesDIY ($)Dealer ($)Price Difference ($)
17,500408040
215,0008016080
322,500120240120
430,000160320160
537,500200400200
645,000240480240
752,500280560280
860,000320640320
 
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I guess it really depends on what your risk tolerance is as most dealerships will typically try to deny warranty work as much as possible. It's definitely much more expensive at around $80 per oil change at the dealer versus DIY which is around $40, especially if you are purchasing the engine oil from Costco or somewhere cheaper and then getting the oil pan gasket/oil filter as well. In my opinion, I would DIY when the warranty period (5 years/60,000 miles) is over since the dealership keeps service records of the vehicle automatically and any claims that you "broke the vehicle" during the ownership of the vehicle can easily be refuted if this issue ever arises.

Looking at the 2023 CX-5 owners manual, Mazda recommends changing the oil/filter at 7,500 miles (Schedule 1 for U.S. and Puerto Rico) and I know that most people are religious about 5,000 mile oil changes but the below table shows the price savings that I calculated based on either a 5,000 or 7,500 mile oil change interval based on the average price of an oil change from my experience. I normally opt for the 7,500 mile oil change interval as I think 5,000 is a bit overkill for my liking since most of the engine oils nowadays are full synthetic. In addition, more money would be saved by extending the oil changes a little longer but it would really depend on personal preference as there's no wrong answer here.

To conclude, I guess it depends if you would rather save a few hundred bucks for an oil change over the warranty period of the vehicle and have the dealer fight tooth and nail to prove that something was broken during your ownership of the vehicle versus eating that cost and knowing that the onus is on the dealer if SHTF. Reading through the other posts, it seems like there's not a definite answer here but everyone makes a valid point.

5,000 Mile Change Interval
#MilesDIY ($)Dealer ($)Price Difference ($)
15,000408040
210,0008016080
315,000120240120
420,000160320160
525,000200400200
630,000240480240
735,000280560280
840,000320640320
945,000360720360
1050,000400800400
1155,000440880440
1260,000480960480

7,500 Mile Change Interval
#MilesDIY ($)Dealer ($)Price Difference ($)
17,500408040
215,0008016080
322,500120240120
430,000160320160
537,500200400200
645,000240480240
752,500280560280
860,000320640320

For one thing, you're assuming that there is a risk if you DIY. Keep your receipts and keep good records and the risk drops to zero. Your warranty can't be legally voided.

Since you're comparing the costs of DIY vs. having the dealer do the work. How about factoring your time into the equation? What's your time worth? What's your aggravation level? How long will you be sitting in the dealer's waiting room twiddling your thumbs? We're assuming that the work is done correctly, and if it isn't? It happens, people screw things up from time to time, and being people, they may try to cover up their mistake. If you DIY and you screw something up, you won't be trying to hide it will you?

What's your peace of mind worth?

YMMV
 
For one thing, you're assuming that there is a risk if you DIY. Keep your receipts and keep good records and the risk drops to zero. Your warranty can't be legally voided.

Since you're comparing the costs of DIY vs. having the dealer do the work. How about factoring your time into the equation? What's your time worth? What's your aggravation level? How long will you be sitting in the dealer's waiting room twiddling your thumbs? We're assuming that the work is done correctly, and if it isn't? It happens, people screw things up from time to time, and being people, they may try to cover up their mistake. If you DIY and you screw something up, you won't be trying to hide it will you?

What's your peace of mind worth?

YMMV
There's always a risk associated with everything and that's why I mentioned risk tolerance level as we all can choose what we do with the vehicle, whether we have it serviced at the dealership or if we go through the DIY route. I see having the dealership performing the oil changes at their presence as me playing it safe and not have to go through the hassle of me recording a video of myself with a timestamp and everything during the warranty period of the vehicle so I do not mind eating that few hundred dollar cost of oil changes over that span of time.

Like you said, it also depends on what the time is worth to each individual as well. Some people may have more disposable income and can be doing other work while having the oil changed at the dealership or perhaps they are irritated waiting for it to be finished but it comes down to personal preference.

Quantifying the oil changes, there's a few other variables as well such as:
  1. Jacking up the vehicle
  2. Placing jack stands
  3. Getting the tools out
  4. Removing the old filter
  5. Undoing the drain bolt and waiting for the oil to drain
  6. Pouring new engine oil
  7. Pouring the used engine oil into an old oil canister
  8. Transporting that used oil for recycling at the nearest auto parts store
If it's about saving time, it isn't really saving all that much since most of us don't have a two post lift like the dealership/mechanic and we still need to transport that oil to the nearest auto parts store to recycle but if it's about saving money, then yes I would agree. If the dealer screws up the oil change, it's easier to go back and have them fix the issue as they were the last ones to touch the vehicle but I get the point of DIY and then ensuring that the work was done properly.
 
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