Rear Diff. Fluid, Transfer Case Fluid, Fuel Injector Cleaning

Hi.

I bought a 2017 CX-9 in August at 56,000 kms (35,000 miles) and four months later I am at 60,000 kms and just put winter tires on at the dealer.

Three weeks ago the wrench came on, which I understand is an oil or maintenance reminder. I confirmed with the Audi dealership I bought the car from that they changed the oil and checked all fluids, etc. prior to me picking it up. They did not put their own oil reminder sticker on the windshield and just left the old one from the previous owner in a city an hour away. Anyway, yesterday the Mazda dealer confirmed that oil looks good and level is fine and they reset it to the right interval. The invoice says it's reset to come up again in February, six months after the oil change at the Audi dealer. Though I will probably only be at 5k at that point.

Also on that invoice though, it says I am due (recommended) for those three things in the subject line come February. These are new to me and I'm wondering if that's something the rest of you here do. Are they necessary things you have to keep on top of or is it just the dealer trying to upsell me?

In the manual, under Scheduled Maintenance it says Rear differential oil *5, Transfer oil *5. I assume these are the same thing I'm talking about? The *5 simply means replace if submerged in water. So on the table it didn't say "I" for inspect or "R" for replace at any of the intervals.

For the fuel injector, do you guys instead just buy a fuel injector cleaner for a few bucks and use every 5k or 7.5k or whatever?

Invoice:
RECOMMENDATIONS---------------------------------------------------------------------
REAR DIFFERENTIAL FLUID = $165.95 + TAX
TRANSFER CASE FLUID = $165.95 + TAX
FUEL INJECTOR CLEANING = $156.95 + TAX
 
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That is absolutely an upsell. If you follow the actual manufacturer recommendations, not the dealer 'recommended' schedule, you'll save a ton over the years. On the other hand, I don't buy the 'lifetime' fluid either. I change transmission and transfer case fluid at some point around 60 to 80K miles and differentials around 100K.

I would note that I have a previous gen model so I do the transfer case every 30K or so, but that's due to known issues with that vehicle and the poor design and placement of the transfer case. (Thanks Ford)....
 
Follow what it says in the Scheduled Maintenance. That is what's required to maintain the warranty, nothing else.

Additionally, you don't have to have services done at the dealership (unless you have an extended warranty, some of those require you to service at specific locations and use OEM parts only). You can have the work done at a trusted independent mechanic, or you can do it yourself. You simply need to keep a detailed log of what work/inspections were done at specific dates/mileage milestones, and hold on to all receipts for work done and parts purchased. Try to stick to OEM parts whenever you can to avoid any potential warranty claim headaches.

If a service isn't mentioned in the Owner's Manual, it's likely not needed. That said, like @rowlands57, I don't buy the "lifetime" fluid claim and I would probably change the transmission and diff fluid at some point if I planned to keep the car for a long time.

Further, unless your fuel economy is noticeably lower than the EPA rating of 20 mpg city and 26 mpg highway, there's probably no reason to do any kind of fuel injector service/cleaning. If you do have a significant decrease in fuel economy, you'd want to find out what the "fuel injector cleaning" actually involves. Some places will simply use a $20 bottle of fuel system cleaner that you could have bought yourself, while others may actually use special equipment to test each injector. Also, in the Owner's Manual, Mazda specifically states that fuel additives should not be used at all.

 
Thanks guys.

Considering my '17 is at 60,000 kms right now, if I were to do Rear Diff. Fluid and Transfer Case Fluid, does 100k sound about right? I was planning on having this for several years.
 
What a great outfit. Only $332 plus tax to drain and refill two gear boxes under the car. Raise the car, drain .45 L (.48 quart) from them at the same time, refill with less than a liter of gear oil from the same liter bottle. They must love you!

Follow your owner's manual. That's what Mazda wants you to do. It's not your responsibility to help the dealership owner make the next payment on his vacation home.

If I do it myself, I'll use Red Line 75W-85 gear oil. I feel that their gear oils are superior to the usual gear oils. For injector cleaning, with nearly 50,000 miles on my car, I put in a large bottle of Chevron Techron Concentrate cleaning product. I think I might have an inkling of peppier performance. In any case, pick a fuel system cleaner with polyetheramine, PEA, which is highly effective at cleaning the deposits in modern gasoline.
 
Thanks guys.

Considering my '17 is at 60,000 kms right now, if I were to do Rear Diff. Fluid and Transfer Case Fluid, does 100k sound about right? I was planning on having this for several years.
100K kms would be as early as you'd need for the fluids. As others have said, use a quality injector cleaner that you can source anywhere for $20 every so often. For the work not specifically listed in the Mazda Maintenance Schedule I would either DIY or find a quality shop (not the dealer) to do the work. In the long run you, and your wallet, will be happier.

I am not surprised that dealerships have moved the commission hounds to the service department since internet pricing has removed a lot of the antics on the sales floor. F&I is another pit to watch out for but the 'service advisors' have become incentive driven borderline liars.
 
100K kms would be as early as you'd need for the fluids. As others have said, use a quality injector cleaner that you can source anywhere for $20 every so often. For the work not specifically listed in the Mazda Maintenance Schedule I would either DIY or find a quality shop (not the dealer) to do the work. In the long run you, and your wallet, will be happier.

I am not surprised that dealerships have moved the commission hounds to the service department since internet pricing has removed a lot of the antics on the sales floor. F&I is another pit to watch out for but the 'service advisors' have become incentive driven borderline liars.
I can’t speak to all dealerships but I know incentivizing service advisors isn’t that new of a thing. I had a friend that was a service advisor for a Honda dealership in the DFW area back in the late 90s/early 2000s and they ran on this model. The top advisor was pulling well into the $100k range while base salary was maybe around $40k. He ended up finding a new line of work when he finally realized the BS he was spewing to people. I like to think I had a little to do with it by telling him he was no better than a scumbag used car salesman every chance I could, haha.
 
Megaman, sounds like you are in Canada. Just in case you didn’t know, make sure you follow the right maintenance schedule for Canada. It is a different table in the manual and is a bit confusing at first.
 
Yep, service writers are commission salesmen of service work. If they don't sell enough services they get fired. Generally a dealership's new car sales yield low profit. Used cars give a higher profit. The service department is the gold mine.
 
Yep, service writers are commission salesmen of service work. If they don't sell enough services they get fired. Generally a dealership's new car sales yield low profit. Used cars give a higher profit. The service department is the gold mine.
As far as new car sales, that's what they would have you believe.

The internet is largely silent on the issue and the dealer invoicing costs are locked up tighter than fort Knox.

The car manufacturers make their $$ on volume. The real profit makers are the dealerships. Back in the 90's an invoiced Chevy cavalier sold to dealerships for approx. $5000 to 6000... But was MSRP for between $14,000 and $15,000 which most sheep paid. Other Chevy, Ford and Toyota markups were about the same.

yeah, yeah, they do have some overhead costs.

and those car incentives(military, school student, etc.) come off the manufacturer bottom line.

Even in 2005/2006 during the defaulted bank fiasco, was able to get an MSRP $36,000 down to $24,000 and they were still making $$.

Right now they're happy as bears, with no compromise with the escalating prices on the used cars. And they still act like they're in dire straights.

And marking up new vehicles more than MSRP which some manufacturers put a stop to rightly so.

They're profit driven on everything from new cars to used cars to service work. None of it's marginal low profit.

My most recent purchase was bad luck and bad timing as got caught in the most recent auto bubble market and had to pay more than it's worth.

Dealerships are just like banks, always saying they have no money but they build the biggest nicest buildings all over the place.
 
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As far as new car sales, that's what they would have you believe.

The internet is largely silent on the issue and the dealer invoicing costs are locked up tighter than fort Knox.

The car manufacturers make their $$ on volume. The real profit makers are the dealerships. Back in the 90's an invoiced Chevy cavalier sold to dealerships for approx. $5000 to 6000... But was MSRP for between $14,000 and $15,000 which most sheep paid. Other Chevy, Ford and Toyota markups were about the same.

yeah, yeah, they do have some overhead costs.

and those car incentives(military, school student, etc.) come off the manufacturer bottom line.

Even in 2005/2006 during the defaulted bank fiasco, was able to get an MSRP $36,000 down to $24,000 and they were still making $$.

Right now they're happy as bears, with no compromise with the escalating prices on the used cars. And they still act like they're in dire straights.

And marking up new vehicles more than MSRP which some manufacturers put a stop to rightly so.

They're profit driven on everything from new cars to used cars to service work. None of it's marginal low profit.

My most recent purchase was bad luck and bad timing as got caught in the most recent auto bubble market and had to pay more than it's worth.

Dealerships are just like banks, always saying they have no money but they build the biggest nicest buildings all over the place.
the info you are working with is ancient and outdated. The recession in 2007/08 greatly shrunk the gap between invoice and MSRP. Manufacturers at the time raised the invoice price charged to dealers and kept the MSRP the same. Dealers had to basically give cars away just to move inventory and lots of dealerships ended up shutting down. That structure has carried on to today. There are per unit volume bonuses from OEMs but there are no guarantees the targets will be met and pretty much no one has hit them over the last year.

Yes, used car pricing is higher but that is because it costs so much more to buy used cars. People selling/trading 2-3 year old vehicles are getting pretty much what they paid for them. That means higher selling prices than a year ago but the ratio between buying price an selling price is the same.

btw, most manufacturers require dealers to remodel every 7-10 years; that's why there are so few really run down dealerships
 
I just ran top tier fuel in mine.

As to the diff/tx fer case, last time I had it checked was at around 70K miles or something. They said both looked great, and changed the diff fluid begrudgingly, saying it was fine but "your money bro", as I'd taken the car through some 8" or so of fast moving water and have scars from the trauma of doing that in my 2015 and it flooding, lol!
 
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