2017~2025 CX-5 Rear Differential Failure

[jadmt]

ok super easy job..I took just a smidgeon under a full qt to where both were at the brim of the inspection hole and the fluid steadily dripping out...at 45073 miles my fluid looked extremely good. it was however obviously under filled especially in the rear. rear was under 12 ounces and took somewhere around 14-15 ounces to fill to the brim..the front transfer case not so low close to 15 ounces out and around 16 ounces to fill to the brim..
both drain plugs have very little smudge on them and no actual abrasive stuff as it was smooth rubbing between my fingers. the rear had slightly more spudge on the plug and the front barely had any.

it was one of those jobs for me like doing the spark plugs, had I known they would look so good I would have extended the interval..on my plugs I changed at ~40,000 and would have left in another 20,000 miles or so and on these I would easily feel comfortable going 60,000 miles. I might add my car was fully warmed up and had been driven several miles in town driving as well as several at 45-50mph before pulling into my garage.

 

[N7turbo]

I've never done this before so, my question is, should it be filled all the way to the top? Is that what the manual calls for?

 

[BoomerZoomr]

For the past 50+ years, filled to the bottom edge of the fill hole was standard procedure on everything like axles and manual transmissions or transfer cases.
New cars could be something different…

 

[AL Cx5]

ok super easy job..I took just a smidgeon under a full qt to where both were at the brim of the inspection hole and the fluid steadily dripping out...at 45073 miles my fluid looked extremely good. it was however obviously under filled especially in the rear. rear was under 12 ounces and took somewhere around 14-15 ounces to fill to the brim..the front transfer case not so low close to 15 ounces out and around 16 ounces to fill to the brim..
both drain plugs have very little smudge on them and no actual abrasive stuff as it was smooth rubbing between my fingers. the rear had slightly more spudge on the plug and the front barely had any.

it was one of those jobs for me like doing the spark plugs, had I known they would look so good I would have extended the interval..on my plugs I changed at ~40,000 and would have left in another 20,000 miles or so and on these I would easily feel comfortable going 60,000 miles. I might add my car was fully warmed up and had been driven several miles in town driving as well as several at 45-50mph before pulling into my garage.

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ok super easy job..I took just a smidgeon under a full qt to where both were at the brim of the inspection hole and the fluid steadily dripping out...at 45073 miles my fluid looked extremely good. it was however obviously under filled especially in the rear. rear was under 12 ounces and took somewhere around 14-15 ounces to fill to the brim..the front transfer case not so low close to 15 ounces out and around 16 ounces to fill to the brim..
both drain plugs have very little smudge on them and no actual abrasive stuff as it was smooth rubbing between my fingers. the rear had slightly more spudge on the plug and the front barely had any.

it was one of those jobs for me like doing the spark plugs, had I known they would look so good I would have extended the interval..on my plugs I changed at ~40,000 and would have left in another 20,000 miles or so and on these I would easily feel comfortable going 60,000 miles. I might add my car was fully warmed up and had been driven several miles in town driving as well as several at 45-50mph before pulling into my garage.

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I've never knew we could tell if gear lube is contaminated by not rubbing between our fingers. Did you compare the new to the old?

Do you hand calculate you fuel mileage? You might see a drop in mph after 40k mi on your spark plugs.

At today's fuel prices, a small improvement or loss will pay for 4 spark plugs.

I'm on the other end of the spectrum when comes to maintaining my CX5. I like to pick when and where I do maintenence over waiting for it to develop a miss or stops. I've learned that waiting it until it "needs" work takes out other components.

Running with worn spark plugs. One plug missing will run rich a wash the cylinder. Our O2 sensor reads an average, not individual cylinders. If one cylinder rune rich, from a malfunction plug, the O2 over compensates and the other 3 run lean. This could cause detonation and damage the engine. It's important to replace spark plugs before they malfunction for the above reasons...

 

[AL Cx5]

For the past 50+ years, filled to the bottom edge of the fill hole was standard procedure on everything like axles and manual transmissions or transfer cases.
New cars could be something different…

I made a level gauge on my 2500 diff. It is supposed to be 1.5" frome the fill hole. 2006 dinosaur.

I read to fill the Mazda diff to the fill hole. Mine are right to the fill holes.

I being to wonder how much driving style impacts diff life. We see guys who go through differentials and transmissions in heavy duty pickups. The guys who demand the truck move a heavy load and not let the truck slow down when pulling a load up steep grades. Or other forms of abuse. They scream about the initial cost, then low quality components.

Then we have guys who go 400,000+ miles without rebuilding these items.

Back to slow is smooth and smooth is fast. Or you have to pay to play...

At this price point, Mazda is assuming folks drive in a none abusive manor.

This thread is a great reminder that it's a fun drive and know the diff and maybe other items are not up to spirited driving. Get a true sports car for that.

 

[jadmt]

I've never knew we could tell if gear lube is contaminated by not rubbing between our fingers. Did you compare the new to the old?

Do you hand calculate you fuel mileage? You might see a drop in mph after 40k mi on your spark plugs.

At today's fuel prices, a small improvement or loss will pay for 4 spark plugs.

I'm on the other end of the spectrum when comes to maintaining my CX5. I like to pick when and where I do maintenence over waiting for it to develop a miss or stops. I've learned that waiting it until it "needs" work takes out other components.

Running with worn spark plugs. One plug missing will run rich a wash the cylinder. Our O2 sensor reads an average, not individual cylinders. If one cylinder rune rich, from a malfunction plug, the O2 over compensates and the other 3 run lean. This could cause detonation and damage the engine. It's important to replace spark plugs before they malfunction for the above reasons...

I have been change gear oil in diffs since the 70's so I have decent sense of what looks good and what looks bad..the sludge on the magnet was just smooth like creamy peanut butter not gritty like I was expecting. Yes I hand figure every tank and use only Top Tier fuel and usually run 91 octane. spark plugs looked new and gap was spot on. ohms were identical to the new ones (mazda oem) I tend to run mine harder than many and usually run in sport mode. just got back from a 2500 mile road trip (montana, North Dakota and minnesota and back) and only burned non ethanol except for 1 tankful. I do know everybody has to do what makes them comfortable.

 

[AL Cx5]

I have been change gear oil in diffs since the 70's so I have decent sense of what looks good and what looks bad..the sludge on the magnet was just smooth like creamy peanut butter not gritty like I was expecting. Yes I hand figure every tank and use only Top Tier fuel and usually run 91 octane. spark plugs looked new and gap was spot on. ohms were identical to the new ones (mazda oem) I tend to run mine harder than many and usually run in sport mode. just got back from a 2500 mile road trip (montana, North Dakota and minnesota and back) and only burned non ethanol except for 1 tankful. I do know everybody has to do what makes them comfortable. View attachment 382204View attachment 382205

I'm more scientific and want to see a lab report. I've never found clutch mayerial to be gritty unless a major failure.

Does the magnet remove all of the metallic clutch? I put my money it doesn't.

Anyway, sounds like you are enjoying your ride.

I run 93 E free as well, turbo with a tune Thang.

I change our air filter every other oil change, 10k mi turbo deal again. These things add up to less stress on the engine and save in the long run.

Enjoy!!

 

[jadmt]

I'm more scientific and want to see a lab report. I've never found clutch mayerial to be gritty unless a major failure.

Does the magnet remove all of the metallic clutch? I put my money it doesn't.

Anyway, sounds like you are enjoying your ride.

I run 93 E free as well, turbo with a tune Thang.

I change our air filter every other oil change, 10k mi turbo deal again. These things add up to less stress on the engine and save in the long run.

Enjoy!!

North Dakota is pretty cool when it comes to getting good gas. I don't change my air filter every other oil change (that would be about every 7000-8000 miles) but change it often.

 

[nickswhip24]

North Dakota is pretty cool when it comes to getting good gas. I don't change my air filter every other oil change (that would be about every 7000-8000 miles) but change it often.
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wow....$$$$ ....did you ever remove airbox? i did last week...pretty cool setup with drain leg and weep hole's....seemed smart

 

[jadmt]

wow....$$$$ ....did you ever remove airbox? i did last week...pretty cool setup with drain leg and weep hole's....seemed smart

I am still running the stock airbox. what did you replace it with?

 

[Lazy2.5]

I tend to run mine harder than many and usually run in sport mode. View attachment 382205

It's visible - that spark plug has seen plenty of high-rpm use.